
Contents
Precautions
Operating Precautions
User Maintenance
Battery
Mobile Link Precautions
Before Getting Started...
General Guide
Indicators
Navigating Between Modes
Charging
Viewing the Face in the Dark
Useful Features
Linking with a Phone
Getting Ready
Auto Time Adjustment
Configuring Reminder Settings
Configuring World Time Settings
Phone Finder
Configuring Watch Settings
Changing the Home City Summer Time Setting
Checking the Watch Charge Level
Recording Your Current Location (TIME &
PLACE)
Connection
Connecting with a Phone
Disconnecting from Your Phone
Unpairing
If you purchase another phone
Time Adjustment
Time Adjustment Using a Time Signal
Overview
Appropriate Signal Reception Location
Time Signal Reception Ranges
Auto Time Calibration Signal Receive
Manual Time Calibration Signal Receive
Receive Level Indicator
Signal Reception Precautions
Using Watch Operations to Adjust the Time
Setting
Using the Watch in a Medical Facility or
Aircraft
World Time
Using CASIO WATCHES to Configure World
Time City Settings
Checking World Time
World Time City Setting
Swapping Your Home Time and World Time
Alarm
Using CASIO WATCHES to Configure Alarm
Settings
Configuring Alarm Settings
Enabling the Hourly Time Signal
Turning Off an Alarm or the Hourly Time Signal
Moving to Another Time Zone
Stopwatch
Measuring Elapsed Time
Measuring a Split Time
Timing the First and Second Place Finishers
Timer
Using CASIO WATCHES to Configure Timer
Settings
Setting the Countdown Start Time
Using the Timer
Reminder
Creating a Reminder
Checking Reminder Notifications
Other Settings
Changing the Date Display Format
Specifying the Day of the Week Language
Enabling the Button Operation Tone
Configuring Power Saving Function Settings
Resetting Watch Settings
Other Information
City Table
Summer Time Table
Supported Phones
Specifications
Copyrights and Registered Copyrights
Troubleshooting
Watch Operation Guide 3539
1
MA2307-EB
OPUM-H
© 2023 CASIO COMPUTER CO., LTD.

Precautions
Operating Precautions
●
Water Resistance
●
The information below applies to watches
with WATER RESIST or WATER
RESISTANT marked on the back cover.
Water Resistance Under Daily Use
Marking on watch front or on
back cover
No BAR
mark
Example of Daily Use
Hand washing, rain Yes
Water-related work, swimming No
Windsurfing No
Skin diving No
Enhanced Water Resistance Under Daily
Use
5 Atmospheres
Marking on watch front or on
back cover
5BAR
Example of Daily Use
Hand washing, rain Yes
Water-related work, swimming Yes
Windsurfing No
Skin diving No
10 Atmospheres
Marking on watch front or on
back cover
10BAR
Example of Daily Use
Hand washing, rain Yes
Water-related work, swimming Yes
Windsurfing Yes
Skin diving Yes
20 Atmospheres
Marking on watch front or on
back cover
20BAR
Example of Daily Use
Hand washing, rain Yes
Water-related work, swimming Yes
Windsurfing Yes
Skin diving Yes
●
Do not use your watch for scuba diving or
other types of diving that requires air tanks.
●
Watches that do not have WATER RESIST
or WATER RESISTANT marked on the
back cover are not protected against the
effects of sweat. Avoid using such a watch
under conditions where it will be exposed to
large amounts of sweat or moisture, or to
direct splashing with water.
●
Even if a watch is water resistant, note the
usage precautions described below. Such
types of use reduce water resistance
performance and can cause fogging of the
glass.
ー
Do not operate the crown or buttons while
your watch is submersed in water or wet.
ー
Avoid wearing your watch while in the
bath.
ー
Do not wear your watch while in a heated
swimming pool, sauna, or any other high
temperature/high humidity environment.
ー
Do not wear your watch while washing
your hands or face, while doing
housework, or while performing any other
task that involves soaps or detergents.
●
After submersion in seawater, use plain
water to rinse all salt and dirt from your
watch.
●
To maintain water resistance, have the
gaskets of your watch replaced periodically
(about once every two or three years).
●
A trained technician will inspect your watch
for proper water resistance whenever you
have its battery replaced. Battery
replacement requires the use of special
tools. Always request battery replacement
from your original retailer or from an
authorized CASIO service center.
●
Some water-resistant watches come with
fashionable leather bands. Avoid
swimming, washing, or any other activity
that causes direct exposure of a leather
band to water.
●
The inside surface of the watch glass may
fog when the watch is exposed to a sudden
drop in temperature. No problem is
indicated if the fogging clears up relatively
quickly. Sudden and extreme temperature
changes (such as coming into an air
conditioned room in the summer and
standing close to an air conditioner outlet,
or leaving a heated room in the winter and
allowing your watch to come into contact
with snow) can cause it to take longer for
glass fogging to clear up. If glass fogging
does not clear up or if you notice moisture
inside of the glass, immediately stop using
your watch and take it to your original
retailer or to an authorized CASIO service
center.
●
Your water-resistant watch has been tested
in accordance with International
Organization for Standardization
regulations.
●
Band
●
Tightening the band too tightly can cause
you to sweat and make it difficult for air to
pass under the band, which can lead to skin
irritation. Do not fasten the band too tightly.
There should be enough room between the
band and your wrist so you can insert your
finger.
●
Deterioration, rust, and other conditions can
cause the band to break or come off of your
watch, which in turn can cause band pins to
fly out of position or to fall out. This creates
the risk of your watch falling from your wrist
and becoming lost, and also creates the risk
of personal injury. Always take good care of
your band and keep it clean.
●
Immediately stop using a band if you even
notice any of the following: loss of band
flexibility, band cracks, band discoloration,
band looseness, band connecting pin flying
or falling out, or any other abnormality. Take
your watch to your original retailer or to a
CASIO service center for inspection and
repair (for which you will be charged) or to
have the band replaced (for which you will
be charged).
Watch Operation Guide 3539
2

●
Temperature
●
Never leave your watch on the dashboard
of a car, near a heater, or in any other
location that is subject to very high
temperatures. Do not leave your watch
where it will be exposed to very low
temperatures. Temperature extremes can
cause your watch to lose or gain time, to
stop, or otherwise malfunction.
●
Leaving your watch in an area hotter than
+60 °C (140 °F) for long periods can lead to
problems with its LCD. The LCD may
become difficult to read at temperatures
lower than 0 °C (32 °F) and greater than
+40 °C (104 °F).
●
Impact
●
Your watch is designed to withstand impact
incurred during normal daily use and during
light activity such as playing catch, tennis,
etc. Dropping your watch or otherwise
subjecting it to strong impact, however, can
lead to malfunction. Note that watches with
shock-resistant designs (G-SHOCK,
BABY-G, G-MS) can be worn while
operating a chain saw or engaging in other
activities that generate strong vibration, or
while engaging in strenuous sports
activities (motocross, etc.)
●
Magnetism
●
Though a digital watch normally is not
affected by magnetism, very strong
magnetism (from medical equipment, etc.)
should be avoided because it can cause
malfunction and damage to electronic
components.
●
Electrostatic Charge
●
Exposure to very strong electrostatic
charge can cause your watch to display the
wrong time. Very strong electrostatic
charge even can damage electronic
components.
●
Electrostatic charge can cause the display
to go blank momentarily or cause a rainbow
effect on the display.
●
Chemicals
●
Do not allow your watch to come into
contact with thinner, gasoline, solvents,
oils, or fats, or with any cleaners, adhesives,
paints, medicines, or cosmetics that contain
such ingredients. Doing so can cause
discoloration of or damage to the resin
case, resin band, leather, and other parts.
●
Storage
●
If you do not plan to use your watch for a
long time, thoroughly wipe it free of all dirt,
sweat, and moisture, and store it in a cool,
dry place.
●
Resin Components
●
Allowing your watch to remain in contact
with other items or storing it together with
other items for long periods while it is wet
can cause color on resin components to
transfer to the other items, or the color of the
other items to transfer to the resin
components of your watch. Be sure to dry
off your watch thoroughly before storing it
and make sure it is not in contact with other
items.
●
Leaving your watch where it is exposed to
direct sunlight (ultraviolet rays) for long
periods or failure to clean dirt from your
watch for long periods can cause it to
become discolored.
●
Friction caused by certain conditions
(strong external force, sustained rubbing,
impact, etc.) can cause discoloration of
painted components.
●
If there are printed figures on the band,
strong rubbing of the printed area can cause
discoloration.
●
Leaving your watch wet for long periods can
cause fluorescent color to fade. Wipe the
watch dry as soon as possible after it
becomes wet.
●
Semi-transparent resin parts can become
discolored due to sweat and dirt, and if
exposed to high temperatures and humidity
for long periods.
●
Daily use and long-term storage of your
watch can lead to deterioration, breaking, or
bending of resin components. The extent of
such damage depends on usage conditions
and storage conditions.
●
Leather Band
●
Allowing your watch to remain in contact
with other items or storing it together with
other items for long periods while it is wet
can cause the color of the leather band to
transfer to the other items or the color of the
other items to transfer to the leather band.
Be sure to dry off your watch thoroughly with
a soft cloth before storing it and make sure
it is not in contact with other items.
●
Leaving a leather band where it is exposed
to direct sunlight (ultraviolet rays) for long
periods or failure to clean dirt from a leather
band for long periods can cause it to
become discolored.
CAUTION:
Exposing a leather band to rubbing or dirt
can cause color transfer and discoloration.
●
Metal Components
●
Failure to clean dirt from metal components
can lead to formation of rust, even if
components are stainless steel or plated. If
metal components exposed to sweat or
water, wipe thoroughly with a soft,
absorbent cloth and then place the watch in
a well-ventilated location to dry.
●
Use a soft toothbrush or similar tool to scrub
the metal with a weak solution of water and
a mild neutral detergent, or with soapy
water. Next, rinse with water to remove all
remaining detergent and then wipe dry with
a soft absorbent cloth. When washing metal
components, wrap the watch case with
kitchen plastic wrap so it does not come into
contact with the detergent or soap.
●
Bacteria and Odor Resistant Band
●
The bacteria and odor resistant band
protects against odor generated by the
formation of bacteria from sweat, which
ensures comfort and hygiene. In order to
ensure maximum bacteria and odor
resistance, keep the band clean. Use an
absorbent soft cloth to thoroughly wipe the
band clean of dirt, sweat, and moisture. A
bacteria and odor resistant band
suppresses the formation of organisms and
bacteria. It does not protect against rash
due to allergic reaction, etc.
●
Liquid Crystal Display
●
Display figures may be difficult to read when
viewed from an angle.
Note that CASIO Computer Co., Ltd.
assumes no responsibility for any
damage or loss suffered by you or any
third party arising through the use of your
watch or its malfunction.
Watch Operation Guide 3539
3

User Maintenance
●
Caring for Your Watch
Remember that you wear your watch next to
your skin, just like a piece of clothing. To
ensure your watch performs at the level for
which it is designed, keep it clean by
frequently wiping with a soft cloth to keep your
watch and band free of dirt, sweat, water and
other foreign matter.
●
Whenever your watch is exposed to sea
water or mud, rinse it off with clean fresh
water.
●
For a metal band or a resin band with metal
parts, use a soft toothbrush or similar tool to
scrub the band with a weak solution of water
and a mild neutral detergent, or with soapy
water. Next, rinse with water to remove all
remaining detergent and then wipe dry with
a soft absorbent cloth. When washing the
band, wrap the watch case with kitchen
plastic wrap so it does not come into contact
with the detergent or soap.
●
For a resin band, wash with water and then
wipe dry with a soft cloth. Note that
sometimes a smudge like pattern may
appear on the surface of a resin band. This
will not have any effect on your skin or
clothing. Wipe with a cloth to remove the
smudge pattern.
●
Clean water and sweat from a leather band
by wiping with a soft cloth.
●
Not operating a watch crown, buttons, or
rotary bezel could lead to later problems
with their operation. Periodically rotate the
crown and rotary bezel, and press buttons
to maintain proper operation.
●
Dangers of Poor Watch Care
Rust
●
Though the metal steel used for your watch
is highly rust-resistant, rust can form if your
watch is not cleaned after it becomes dirty.
ー
Dirt on your watch can make it impossible
for oxygen to come into contact with the
metal, which can lead to breakdown of
the oxidization layer on the metal surface
and the formation of rust.
●
Rust can cause sharp areas on metal
components and can cause band pins to fly
out of position or to fall out. If you ever notice
any abnormality immediately stop using
your watch and take it to your original
retailer or to an authorized CASIO service
center.
●
Even if the surface of the metal appears
clean, sweat and rust in crevasses can soil
the sleeves of clothing, cause skin irritation,
and even interfere with watch performance.
Premature Wear
●
Leaving sweat or water on a resin band or
bezel, or storing your watch an area subject
to high moisture can lead to premature
wear, cuts, and breaks.
Skin Irritation
●
Individuals with sensitive skin or in poor
physical condition may experience skin
irritation when wearing a watch. Such
individuals should keep their leather band
or resin band particularly clean. Should you
ever experience a rash or other skin
irritation, immediately remove your watch
and contact a skin care professional.
Battery
●
The special rechargeable battery used by
your watch is not intended to be removed or
replaced by you. Use of a rechargeable
battery other than the special one specified
for your watch can damage your watch.
●
The rechargeable (secondary) battery is
charged when the solar panel is exposed to
light, so it does not require regular
replacement as the primary battery
requires. Note, however, that long use or
operating conditions can cause the
capacity or charging efficiency of the
rechargeable battery to deteriorate. If you
feel that the amount of operation provided
by charging is too short, contact your
original retailer or CASIO service center.
Watch Operation Guide 3539
4

Mobile Link Precautions
●
Legal Precautions
●
This watch complies with or has received
approval under the radio laws of various
countries and geographical areas. Using
this watch in an area where it does not
comply with or has not received approval
under applicable radio laws may be a
criminal offense. For details, visit the CASIO
Website.
https://world.casio.com/ce/BLE/
●
Use of this watch inside of aircraft is
restricted under the aviation laws of each
country. Be sure to follow the instructions of
airline personnel.
●
Precautions when using Mobile Link
●
When using this watch in combination with
a phone, keep the watch and phone close
to each other. A range of two meters is
recommended as a guideline, but the local
environment (walls, furniture, etc.), the
structure of a building, and other factors
may require a much closer range.
●
This watch can be affected by other devices
(electrical devices, audio-visual equipment,
office equipment, etc.) In particular, it can
be affected by operation of a microwave
oven. The watch may not be able to
communicate normally with a phone if a
microwave oven is operating nearby.
Conversely, this watch may cause noise in
radio reception and the video image of a TV.
●
Bluetooth of this watch uses the same
frequency band (2.4 GHz) as wireless LAN
devices, and use of such devices in close
proximity of this watch may result in radio
interference, slower communication
speeds and noise for the watch and the
wireless LAN device, or even
communication failure.
●
Stopping Radio Wave Emission by This
Watch
The watch is emitting radio waves whenever
e
is flashing or displayed.
In addition, the watch also connects phone
automatically four times a day to adjust its time
setting.
When in a hospital, on an aircraft, or in any
other area where the use of radio waves is not
allowed, use the operation below to stop radio
wave generation.
●
Stopping Radio Wave Generation
Press any button to terminate the Bluetooth
connection.
Connected Disconnected
●
Disabling Auto Time Adjustment
Configure CASIO WATCHES settings to
disable time adjustment between the watch
and phone.
l
Using the Watch in a Medical Facility or
Aircraft
Watch Operation Guide 3539
5

Before Getting
Started...
This section provides an overview of the watch
and introduces convenient ways it can be
used.
Watch Features
●
Phone Linking
The watch supports connection and
communication with a Bluetooth capable
phone.
●
Solar Charging
Sunlight and artificial light generate
electricity for watch operation as it charges.
●
Time Signal Reception
The watch receives a radio signal
containing time information and uses it to
keep its time setting accurate.
●
World Time
The current time can be displayed for any
one of 39 cities around the globe, as well as
for UTC (Coordinated Universal Time).
You can select up to five cities in the World
Time Mode.
●
Alarm
An alarm sounds whenever a time specified
by you is reached.
●
Stopwatch
The stopwatch measures elapsed time in
units of one second (1/100 second for the
first hour) up to 24 hours.
●
Timer
Countdown from a start time specified by
you. An alarm sounds when the countdown
reaches zero.
Note
●
The illustrations included in this
operation guide have been created to
facilitate explanation. An illustration
may differ somewhat from the item it
represents.
General Guide
③
②①
A Day of the week
B Month, day
C Hour, minute, second
A button
Holding down this button for at least two
seconds in any mode displays the setting
screen.
B button
Press to turn on illumination.
C button
Each press cycles between watch modes.
In any mode, hold down this button for at least
one second to return to the Timekeeping
Mode.
D button
Pressing this button while any setting screen
is displayed will change the setting.
Indicators
②③ ④①
⑧
⑨
⑤
⑩
⑪
⑥
⑦
A Displayed while there is a Bluetooth
connection between the watch and a
phone.
B Displayed while Power Saving is enabled.
C Displayed while Auto Light is enabled.
D Displayed after time adjustment using
time signal reception or connection with a
phone was successful.
The [RCVD] indicator will disappear in the
cases below.
●
After you use watch operations to
change Home City settings (time and
date, city, summer time)
●
After the watch switches between
standard time and summer time
●
After a time signal receive operation
fails
●
After a phone-based time adjustment
operation fails
E Displayed during p.m. times while 12-hour
timekeeping is being used.
F Displayed while the watch is indicating
summer time.
G Displayed when battery power is low.
H Displayed while an alarm is turned on.
I Displayed while the hourly time signal is
enabled.
J Displayed while the button operation tone
is disabled.
K Displayed while the snooze alarm is
turned on.
Watch Operation Guide 3539
6

Navigating Between Modes
Each press of (C) cycles between watch
modes.
●
In any mode, hold down (C) for at least one
second to return to the Timekeeping Mode.
C
C
C
C
C
World Time Mode
Alarm Mode
Timer Mode
Stopwatch Mode
Timekeeping Mode
●
Connecting with a Phone
Hold down (C) for at least three seconds to
connect with a phone.
●
To disconnect, press any button.
C
After connectionBefore connection
Any button
Charging
This watch runs on power supplied from a
rechargeable (secondary) battery that is
charged by a solar panel. The solar panel is
integrated into the face of the watch, and
power is generated whenever the face is
exposed to light.
●
Charging the Watch
When you are not wearing the watch, put it in
a location where it is exposed to bright light.
While you are wearing the watch, make sure
that its face (solar panel) is not blocked from
light by the sleeve of your clothing. Power
generation efficiency is reduced even when
the face of the watch is blocked only partially.
NOYES
Important!
●
Some light sources and environments
can cause the watch to become
extremely hot during charging, which
creates the risk of burn injury and
damage to internal watch
components.
Avoid charging the watch under
conditions like the ones described
below, where the temperatures may
exceed 60 °C (140 °F).
ー
On the dashboard of a vehicle
parked in the sun
ー
Near incandescent lamps, camera
lights, halogen lamps, or other
sources of heat
ー
In locations exposed to direct
sunlight for long periods and other
hot locations
●
Low Battery
A low battery will cause [LOW] to flash and will
disable the functions below.
●
Time signal reception
●
Illumination
●
Sounds (alarm, etc.)
●
Connection with a phone
If the charge level drops even further, [CHG]
will flash. If this happens, all functions are
disabled.
●
Dead Battery
The digital display will go blank if the battery
goes dead. Memory data is lost, and watch
settings are returned to their initial factory
defaults.
Important!
●
Should the battery go low or go dead,
expose the face (solar panel) to light as
soon as possible.
●
Exposing the watch to light while its
battery is dead will cause [CHG] to
start flashing. Keep the watch exposed
to light until the current time appears on
the display.
Note
●
If [R] is flashing, it means that all
functions, except for timekeeping, are
disabled due to high momentary
battery power consumption.
l
[R] is flashing on the digital display.
Watch Operation Guide 3539
7

●
Charging Time Guidelines
The table below shows guidelines for
approximate charging times.
Charging Times Required for 1 Day of
Operation
Light Level (Lux)
Approximate
Charging Time
50,000 8 minutes
10,000 30 minutes
5,000 48 minutes
500 8 hours
Charge Recovery Times
●
Sunny day, outdoors (50,000 lux)
Dead battery
n
Medium
charge
3 hours
Medium charge
n
High
charge
35 hours
High charge
n
Full charge
10 hours
●
Sunny day, near a window (10,000 lux)
Dead battery
n
Medium
charge
10 hours
Medium charge
n
High
charge
132 hours
High charge
n
Full charge
36 hours
●
Overcast day, near a window (5,000 lux)
Dead battery
n
Medium
charge
16 hours
Medium charge
n
High
charge
214 hours
High charge
n
Full charge
58 hours
●
Indoor fluorescent lighting (500 lux)
Dead battery
n
Medium
charge
209 hours
Medium charge
n
High
charge
-
High charge
n
Full charge
-
Note
●
Actual charging time depends on the
charging environment, watch settings,
and other factors.
●
Power Saving Function
Leaving the watch in a dark location for about
one hour between the hours of 10 p.m. and 6
a.m. will cause the display to go blank, and the
watch to enter Level 1 power saving. If the
watch is left in this condition for six or seven
days, the watch will enter Level 2 power
saving.
Power Saving Level 1 :
Digital display goes blank to save power. The
watch can connect with a phone at this level.
Power Saving Level 2 :
Digital display goes blank to save power. All
functions are disabled.
Recovering from Power Saving Operation
Use one of the operations below to exit power
saving.
●
Press any button.
●
Move the watch to a bright location.
●
Trigger auto light by angling the watch
towards your face.
Note
●
The watch will not enter power saving
in the cases below.
ー
Alarm Mode
ー
While in the Stopwatch Mode
ー
While in the Timer Mode
●
You can enable or disable Power
Saving.
l
Configuring Power Saving
Function Settings
●
Note that the watch also may enter
power saving if its face is blocked from
light by your sleeve while you are
wearing it.
Viewing the Face in the Dark
The watch has a light that illuminates the face
for viewing in the dark.
●
To illuminate the face manually
Press (B) to turn on illumination.
●
Illumination will turn off automatically if an
alarm starts to sound.
Important!
●
Frequent use of illumination will run
down the battery.
Note
●
Display illumination is disabled when
any one of the conditions below exists.
ー
Alarm, timer alert, or other beeper
sounding
ー
Time calibration reception in
progress
●
To illuminate the face when Auto Light
is enabled
If Auto Light is enabled, face illumination will
turn on automatically whenever the watch is
positioned at an angle of 40 degrees or more.
40
degrees
or more
Watch Operation Guide 3539
8

Important!
●
Auto Light may not operate properly
when the watch is at a horizontal angle
of 15 degrees or greater from
horizontal as shown in the illustration
below.
●
Auto Light may operate unintentionally
and run down the battery if the watch
is blocked from light by your sleeve.
●
Electro-static charge or magnetism
can interfere with proper auto light
operation. If this happens, try lowering
your arm and then angle it towards
your face again.
●
When moving the watch you may note
a slight rattling sound. This is due to
operation of the auto light switch,
which determines the current
orientation of the watch. It does not
indicate malfunction.
Note
●
Auto Light is disabled when any one of
the conditions below exists.
ー
Alarm, timer alert, or other beeper
sounding
ー
Time calibration reception in
progress
●
Configuring the Auto Light Setting
1. Enter the Timekeeping Mode.
l
Navigating Between Modes
2. Hold down (B) for at least three seconds
to toggle Auto Light between enabled and
disabled.
●
[LT] is displayed while Auto Light is
enabled.
On
Note
●
Auto Light is disabled while [CHG] is
shown on the display.
●
Specifying the Illumination Duration
You can select either two seconds or four
seconds as the illumination duration.
1. Enter the Timekeeping Mode.
l
Navigating Between Modes
2. Hold down (A) for at least two seconds.
Release the button when the name of the
currently selected Home City appears on
the display.
Home City
3. Press (C) 12 times to display [LIGHT].
4. Press (D) to select an illumination
duration.
[2]: 2-second illumination
[4]: 4-second illumination
5. Press (A) to exit the setting screen.
Useful Features
Pairing the watch with your phone makes a
number of the watch’s features easier to use.
Auto time adjustment
l
Auto Time Adjustment
12:30
Selection of More Than 300 World Time
cities
l
Configuring World Time Settings
Recording of Anniversaries and
Appointments
l
Configuring Reminder Settings
In addition, a number of other watch settings
can be configured using your phone.
To transfer data to a watch and to
configure settings, you first need to pair
the watch with your phone.
l
Getting Ready
●
Your phone needs to have the CASIO
“CASIO WATCHES” app installed to pair
with the watch.
Watch Operation Guide 3539
9

Linking with a Phone
While there is a Bluetooth connection
between the watch and phone (Mobile Link),
the watch’s current time setting is adjusted
automatically. You can also change the
watch’s other settings.
Note
●
This function is available only while
CASIO WATCHES is running on the
phone.
●
This section describes watch and
phone operations.
X
: Watch operation
Y
: Phone operation
Getting Ready
To use your watch in combination with a
phone, you first need to pair them. Perform the
steps below to pair the watch with a phone.
●
A
Install the app on your phone.
In Google Play or the App Store, search for the
“CASIO WATCHES” phone app and install it
on your phone.
●
B
Configure Bluetooth settings.
Enable the phone’s Bluetooth.
Note
●
For details about setting procedures,
see your phone documentation.
●
C
Pair the watch with a phone.
Before you can use the watch in combination
with a phone, you first need to pair them.
1. Move the phone to be paired with close to
(within one meter of) the watch.
2.
Y
Tap the “CASIO WATCHES” icon.
●
Tap on the “My Watch” tab. Next,
select the applicable product name.
3.
X
Hold down (C) for at least three
seconds. Release the button when
e
and
[CNCT] start to flash.
4.
Y
Perform the operation shown on the
screen of the phone to be paired with.
●
When a connection is established
between the watch and phone,
e
and
[CNCT] will stop flashing and remain on
the display.
●
If pairing fails for some reason, [ERR]
will appear on the display momentarily
and then the watch will return to the
Timekeeping Mode. Perform the pairing
procedure again from the beginning.
Pairing completePairing started
Note
●
The first time you start up CASIO
WATCHES phone app, a message will
appear on your phone asking if you
want to enable location information
acquisition. Configure settings to allow
background use of location
information.
Auto Time Adjustment
Your watch will connect with a phone at preset
times each day and adjust its time settings
automatically.
●
Using This Function
Your watch adjusts its time setting four times
a day according to a preset schedule. If you
leave your watch in the Timekeeping Mode, it
will perform the adjustment operation
automatically as you go about your daily life,
without any operation required by you.
12:30
Important!
●
The watch may not be able to perform
auto time adjustment under the
conditions described below.
ー
While the watch is too far away from
its paired phone
ー
While communication is not possible
due to radio interference, etc.
ー
While the phone is updating its
system
ー
While the CASIO WATCHES phone
app is not running on the phone
Note
●
If there is a World Time City specified
with the CASIO WATCHES phone
app, its time will also be adjusted
automatically.
●
The watch will connect with the phone
and perform auto time adjustment at
around 12:30 a.m., 6:30 a.m., 12:30
p.m. and 6:30 p.m. The connection is
automatically terminated after auto
time adjustment is complete.
●
Time signal auto receive will be
performed if there has been no auto
time adjustment based on connection
between the watch and phone for more
than one day.
Watch Operation Guide 3539
10

●
Triggering Immediate Time Adjustment
The watch’s time setting will be adjusted
automatically whenever you establish a
connection between the watch and a phone.
Whenever you want to trigger immediate time
adjustment, perform the procedure below to
connect with a phone.
1.
X
Enter the Timekeeping Mode.
l
Navigating Between Modes
2. Move the phone close to (within one meter
of) the watch.
3.
X
Press (D).
[TIME] flashes to indicate that the watch
has started the connection operation.
Once the watch and phone are
connected, [OK] will appear, and then the
watch will adjust its time setting based on
information from the phone.
●
At this time your current location is
recorded by your phone.
After time adjustmentTrying to connect
Note
●
The connection is terminated
automatically after time adjustment is
complete.
●
If time adjustment fails for some
reason, [ERR] will appear.
●
[RCVD] flashes when the receive
operation starts, and [RCVD] stops
flashing after it is complete.
Configuring Reminder
Settings
After you use CASIO WATCHES to create
reminders, appointments, anniversaries, or
other events you need to remember, you can
check them on the watch.
●
You can have up to five reminders
registered.
1.
Y
Tap the “CASIO WATCHES” icon.
2.
X
Hold down (C) for at least three
seconds. Release the button when
e
and
[CNCT] start to flash.
●
When a connection is established
between the watch and phone,
e
and
[CNCT] will stop flashing and remain on
the display.
●
If connection fails for some reason,
[ERR] will appear on the display
momentarily and then the watch will
return to the Timekeeping Mode.
Trying to connect
Connected
3.
Y
Follow the instructions that appear on
the screen to configure reminder settings.
●
You can input up to 18 alphanumeric
characters as a reminder title.
Note
●
To prevent the appointments from
being displayed on the watch, use
CASIO WATCHES to turn off the
reminder setting.
Configuring World Time
Settings
Specifying a World Time City with the CASIO
WATCHES phone app causes the watch’s
World Time City to change accordingly.
Settings can be configured to perform auto
summer time switching for the World Time
City.
Note
●
The CASIO WATCHES phone app
World Time lets you select from among
approximately 300 cities as the World
Time City.
●
You can use the CASIO WATCHES
phone app to configure settings for
user cities that are not included in the
watch’s built-in World Time Cities. You
must use the CASIO WATCHES
phone app to select a user city as your
World Time City.
Watch Operation Guide 3539
11

●
To select a World Time City
1.
Y
Tap the “CASIO WATCHES” icon.
2.
X
Hold down (C) for at least three
seconds. Release the button when
e
and
[CNCT] start to flash.
●
When a connection is established
between the watch and phone,
e
and
[CNCT] will stop flashing and remain on
the display.
●
If connection fails for some reason,
[ERR] will appear on the display
momentarily and then the watch will
return to the Timekeeping Mode.
Trying to connect
Connected
3.
Y
Perform the operation shown on the
phone screen. The World Time setting will
be reflected on the watch.
●
Creating a User City
In addition to the approximately 300 cities
available with CASIO WATCHES, you can
specify a location on an on-screen map and
create a user city.
1.
Y
Tap the “CASIO WATCHES” icon.
2.
X
Hold down (C) for at least three
seconds. Release the button when
e
and
[CNCT] start to flash.
●
When a connection is established
between the watch and phone,
e
and
[CNCT] will stop flashing and remain on
the display.
●
If connection fails for some reason,
[ERR] will appear on the display
momentarily and then the watch will
return to the Timekeeping Mode.
Trying to connect
Connected
3.
Y
Perform the operation shown on the
phone screen. The World Time setting will
be reflected on the watch.
Note
●
You can have up to five locations
registered as user cities.
●
You can assign a name up to 18
characters long to each user city.
●
Configuring the Summer Time Setting
1.
Y
Tap the “CASIO WATCHES” icon.
2.
X
Hold down (C) for at least three
seconds. Release the button when
e
and
[CNCT] start to flash.
●
When a connection is established
between the watch and phone,
e
and
[CNCT] will stop flashing and remain on
the display.
●
If connection fails for some reason,
[ERR] will appear on the display
momentarily and then the watch will
return to the Timekeeping Mode.
Trying to connect
Connected
3.
Y
Perform the operation shown on the
phone screen to select a summer time
setting.
●
“Auto”
The watch switches between standard
time and summer time automatically.
●
“OFF”
The watch always indicates standard
time.
●
“ON”
The watch always indicates summer
time.
Note
●
While the summer time setting is
“Auto”, the watch will switch between
standard time and summer time
automatically. You do not need to
switch between standard time and
summer time manually. Even if you are
in an area that does not observe
summer time, you can leave the
watch’s summer time setting as “Auto”.
●
Changing the time setting manually
with a watch operation will cancel auto
standard time/summer time switching.
●
For information about summer time
periods, refer to the “Summer Time
Table” or CASIO WATCHES.
Watch Operation Guide 3539
12

●
Swapping Your World Time and Home
Time
1.
Y
Tap the “CASIO WATCHES” icon.
2.
X
Hold down (C) for at least three
seconds. Release the button when
e
and
[CNCT] start to flash.
●
When a connection is established
between the watch and phone,
e
and
[CNCT] will stop flashing and remain on
the display.
●
If connection fails for some reason,
[ERR] will appear on the display
momentarily and then the watch will
return to the Timekeeping Mode.
Trying to connect
Connected
3.
Y
Perform the operation shown on the
phone screen to swap your Home Time
with your World Time.
Note
●
Auto time adjustment does not work for
24 hours after swapping of the Home
Time and World Time.
Phone Finder
You can use phone finder to trigger a tone on
the phone to make it easy to find. The tone is
forced to sound even if the phone is in vibrate
mode.
Important!
●
Do not use this function in areas where
phone call tones are restricted.
●
The tone sounds at a high volume. Do
not use this function when listening to
phone output over earphones.
1.
X
If the watch is connected with a phone,
press any button to terminate the
connection.
Connected Disconnected
2.
X
If the watch is in any mode besides the
Timekeeping Mode, hold down (C) for at
least one second to enter the
Timekeeping Mode.
3.
X
Hold down (D) for at least five seconds.
Release the button when
e
and [FIND]
start to flash.
The phone will sound a tone when it
establishes a connection with the watch.
●
It will take a few seconds before the
phone tone sounds.
Sounding phone
alert sound
Getting ready to
connect with phone
4.
X
Press any button to stop the tone.
●
You can press any watch button to stop
the phone tone only during the first 30
seconds after it starts to sound.
Configuring Watch Settings
Alarm time, timer start time, and other settings
can also be configured using CASIO
WATCHES.
1.
Y
Tap the “CASIO WATCHES” icon.
2.
X
Hold down (C) for at least three
seconds. Release the button when
e
and
[CNCT] start to flash.
●
When a connection is established
between the watch and phone,
e
and
[CNCT] will stop flashing and remain on
the display.
●
If connection fails for some reason,
[ERR] will appear on the display
momentarily and then the watch will
return to the Timekeeping Mode.
Trying to connect
Connected
3.
Y
Select the setting you want to change
and then perform the operation shown on
the phone screen.
Watch Operation Guide 3539
13

Changing the Home City
Summer Time Setting
1.
Y
Tap the “CASIO WATCHES” icon.
2.
X
Hold down (C) for at least three
seconds. Release the button when
e
and
[CNCT] start to flash.
●
When a connection is established
between the watch and phone,
e
and
[CNCT] will stop flashing and remain on
the display.
●
If connection fails for some reason,
[ERR] will appear on the display
momentarily and then the watch will
return to the Timekeeping Mode.
Trying to connect
Connected
3.
Y
Perform the operation shown on the
phone screen to change your Home City
summer time setting.
Checking the Watch Charge
Level
Use the procedure below to check the current
charge level with CASIO WATCHES.
1.
Y
Tap the “CASIO WATCHES” icon.
2.
X
Hold down (C) for at least three
seconds. Release the button when
e
and
[CNCT] start to flash.
●
When a connection is established
between the watch and phone,
e
and
[CNCT] will stop flashing and remain on
the display.
●
If connection fails for some reason,
[ERR] will appear on the display
momentarily and then the watch will
return to the Timekeeping Mode.
Trying to connect
Connected
3.
Y
Use CASIO WATCHES to check the
charge level.
Recording Your Current
Location (TIME & PLACE)
While traveling or otherwise on the go, you can
use the procedure below to record your
current location, along with the time and date,
on your phone. Recorded location information
can be viewed on a CASIO WATCHES map
while the watch is connected with your phone.
●
Recording Your Current Location
1.
X
Enter the Timekeeping Mode.
l
Navigating Between Modes
2.
X
When you are in the location you want
to record, press (D).
This records, in phone memory, your
latitude and longitude and the current date
and time, and displays [OK] on the watch.
●
At this time the time settings of your
phone and watch will be synced with
each other.
●
Viewing a Recorded Location on a Map
1.
Y
Tap the “CASIO WATCHES” icon.
2.
Y
Perform the operation shown on the
phone screen to view recorded location
information.
Note
●
You can use CASIO WATCHES to
delete recorded location information.
Watch Operation Guide 3539
14

Connection
Connecting with a Phone
Your watch can connect with a phone that is
paired with it.
●
If the watch is not paired with the phone you
want to connect with, refer to the information
below and pair them.
l
C
Pair the watch with a phone.
●
Connecting with a Phone
1. Move the phone close to (within one meter
of) the watch.
2.
X
Hold down (C) for at least three
seconds. Release the button when
e
and
[CNCT] start to flash.
●
When a connection is established
between the watch and phone,
e
and
[CNCT] will stop flashing and remain on
the display.
●
If connection fails for some reason,
[ERR] will appear on the display
momentarily and then the watch will
return to the Timekeeping Mode.
Trying to connect
Connected
Important!
●
If you have problems establishing a
connection, it could mean that CASIO
WATCHES is not running on your
phone. On your phone’s home screen,
tap the “CASIO WATCHES” icon. After
the app starts up, hold down the
watch’s (C) button for at least three
seconds.
Note
●
The connection will be terminated if
you do not perform any operation on
the watch or phone for a fixed amount
of time.
To specify the connection limit time,
perform the following operation with
CASIO WATCHES: “Watch settings”
n
“Connection time with the app”.
Next, select a setting of 3 minutes, 5
minutes, or 10 minutes.
Disconnecting from Your Phone
Pressing any button will terminate a Bluetooth
connection and return to the Timekeeping
Mode.
Connected Disconnected
Unpairing
Unpairing the watch from a phone requires
both CASIO WATCHES phone app and watch
operations.
●
Deleting Pairing Information from the
CASIO WATCHES phone app
1.
Y
Tap the “CASIO WATCHES” icon.
2.
Y
Perform the operation shown on the
phone screen to unpair.
●
Deleting Pairing Information from the
Watch
1.
X
Hold down (C) for at least one second
to enter the Timekeeping Mode.
2.
X
Hold down (A) for at least two seconds.
Release the button when the name of the
currently selected Home City appears on
the display.
Home City
3.
X
Press (C) twice.
This causes the seconds to flash.
Seconds
4.
X
Hold down (B) for at least three
seconds. This will cause the [PAIR] and
[CLR] indicators to alternate on the
display. Release the button when only
[CLR] is displayed.
This deletes the pairing information from
the watch and returns to the timekeeping
display.
5.
X
Press (A) to return to the Timekeeping
Mode.
If you purchase another phone
You need to perform the pairing operation
whenever you want to establish a Bluetooth
connection with a phone for the first time.
l
Deleting Pairing Information from the
Watch
l
C
Pair the watch with a phone.
Watch Operation Guide 3539
15

Time Adjustment
Your watch can obtain date and time
information by connecting with a phone and by
receiving time signals, which it uses to adjust
its settings.
Important!
●
When you are on an aircraft or in any
other location where radio signals may
cause problems, enable the watch’s
Airplane Mode to disable connection
with your phone.
l
Using the Watch in a Medical
Facility or Aircraft
Referring to the information below, configure
the time setting in accordance with the method
that suits your own lifestyle.
Do you use a phone?
Time adjustment by connecting with your
phone is recommended.
l
Auto Time Adjustment
12:30
Can you receive a time signal in your area?
While the watch’s Home Time City setting
is one where a time signal can be
received, the watch’s time and day
settings can be adjusted in accordance
with the signal.
l
Time Signal Reception Ranges
l
Setting a Home City
Other than the above.
If you are unable to connect with a phone
and are unable to receive a time signal,
you can perform watch button operations
to adjust its time setting.
l
Using Watch Operations to Adjust the
Time Setting
Time Adjustment Using a
Time Signal
Overview
The watch’s time and day settings can be
configured in accordance with a received time
calibration signal.
Important!
●
In order to make it possible for the
current time setting to be adjusted
correctly based on time calibration
signal reception, you need to specify
the time zone where you are using the
watch.
●
If the watch was unable to connect with
a phone even once for time adjustment
during the previous day while
connection with a phone is being used,
it will automatically try to receive a time
calibration signal.
Note
●
Areas where time calibration signal
reception is supported are limited.
When the watch is in an area where
time calibration signal reception is not
possible, connect with a phone to
adjust time and day settings.
l
Time Signal Reception Ranges
Watch Operation Guide 3539
16

Appropriate Signal Reception
Location
A time calibration signal can be received while
the watch is near a window.
●
Position the watch so its 12 o’clock side is
facing the window.
●
Keep metal objects away from the watch.
●
Do not move the watch.
●
Do not perform any operation on the watch.
12 o'clock
Note
●
You may experience time calibration
signal reception problems in the areas
described below.
ー
Among or near buildings
ー
While riding in a vehicle
ー
Near household appliances, office
machines, mobile phones, etc.
ー
On a construction site, in an airport,
or any other location where radio
wave interference occurs
ー
Near high-voltage lines
ー
In mountainous areas or behind a
mountain
Time Signal Reception Ranges
●
Japan (JJY)
The Japan time signal radio stations are
located on Mt. Otakadoya in Fukushima and
Mt. Hagane in Fukuoka/Saga.
The reception range of the Japanese time
signals is approximately 1,000 km from each
transmission station.
●
China (BPC)
The China time signal radio station is located
in Shangqiu, Henan Province, China.
The reception range of the Chinese time
signal is approximately 1,500 km from the
transmission station.
●
United States (WWVB)
The United States time signal radio station is
located in Fort Collins, Colorado.
The reception range of the U.S. time signal is
approximately 3,000 km from the transmission
station.
●
U.K. (MSF)/Germany (DCF77)
The U.K. time signal radio station is located in
Anthorn, Cumbria.
The German time signal radio station is
located in Mainflingen, southeast of Frankfurt.
The reception range of the U.K. and German
time signals is approximately 1,500 km from
each transmission station.
Note
●
Even if you are within the normal
reception range of a time calibration
signal, reception may be made
impossible by the following factors:
geographic contours, weather, the
season, the time of day, wireless
noise.
●
A time calibration signal cannot be
received while the city selected as your
Home City is one that does not support
signal reception.
Auto Time Calibration Signal
Receive
An automatic time calibration signal receive
operation is performed and the time and day
settings are adjusted between midnight and
5:00 a.m. Once a signal receive operation is
successful, no more auto receive operations
are performed that day.
1. Place the watch near a window or some
other location appropriate for signal
reception.
●
[RCVD] flashes while time signal
reception is in progress.
●
When the receive operation is
successful, the time and day settings
are adjusted automatically, and the
[RCVD] indicator appears.
Note
●
Reception takes anywhere from about
two minutes to about 10 minutes. It can
take as long as 20 minutes.
Manual Time Calibration Signal
Receive
1. Place the watch near a window or some
other location appropriate for time signal
reception.
2. Enter the Timekeeping Mode.
l
Navigating Between Modes
3. Hold down (D) for at least two seconds
until [RCVD] flashes.
This indicates that the receive operation
has started. After the receive operation is
complete, the watch’s time and day
settings will be adjusted accordingly.
Receive level indicator
●
The level indicator shows the signal
level ([L1], [L2], [L3]) while a receive
operation is in progress.
l
Receive Level Indicator
Watch Operation Guide 3539
17

Note
●
When a receive operation is
successful, [RCVD] will appear, and
the time and day settings will be
adjusted automatically.
●
If a receive operation fails for some
reason, [RCVD] disappears and [ERR]
appears on the display. To return to the
unadjusted timekeeping display, press
any button.
●
The receive operation takes anywhere
from about two minutes to about 10
minutes. It can take as long as 20
minutes.
●
Time calibration signal reception is
better at night than during the day.
Receive Level Indicator
While a receive operation is in progress, its
current status is indicated on the display as
shown below. Use the level indicator to find a
location where signal reception is stable.
Receive level indicator
StableUnstable
Note
●
It takes about 10 seconds for time
signal reception conditions to stabilize.
●
Reception conditions are affected by
weather, the time of day, the
surrounding environment, etc.
Signal Reception Precautions
●
When the watch is unable to adjust its time
in accordance with a calibration signal for
some reason, average timekeeping
accuracy is within ±15 seconds per month.
●
Note that an internal decoding process the
watch performs after it receives a signal
may cause the time setting to be slightly off
(by less than one second).
●
Time calibration signal reception is not
possible under the conditions described
below.
ー
While battery power is low
ー
While the watch is in the Stopwatch
Mode, Timer Mode, or Alarm Mode
ー
When the watch is at Level 2 power
saving
ー
While a timer countdown operation is in
progress
ー
While auto time adjustment is disabled
ー
While the Home City area setting is one
where time signal reception is not
possible
ー
While the watch is outside the time signal
reception range
●
When the receive operation is successful,
the time and/or day settings will be adjusted
automatically. Summer time will not be
applied correctly in the case described
below.
ー
When the summer time start date and
time, end date and time, or other rules are
changed by authorities
●
As of July 2022, China does not observe
summer time. If China starts to observe
summer time in the future, the time
displayed by the watch for China may not be
correct.
Using Watch Operations to
Adjust the Time Setting
If your watch cannot connect with a phone for
some reason, you can use watch operations
to adjust date and time settings.
●
Setting a Home City
Use the procedure in this section to select a
city to use as your Home City. If you are in an
area that observes summer time, you can also
configure a summer time setting.
Note
●
The initial factory default summer time
setting for all cities is [AUTO]. In many
cases, the [AUTO] setting lets you use
the watch without switching between
summer time and standard time.
1. Enter the Timekeeping Mode.
l
Navigating Between Modes
2. Hold down (A) for at least two seconds.
Release the button when the name of the
currently selected Home City appears on
the display.
Home City
3. Use (B) and (D) to change the Home City
setting.
●
Holding down (B) or (D) scrolls through
settings at high speed.
●
For details refer to the information
below.
l
City Table
4. Press (C).
Watch Operation Guide 3539
18

5. Use (D) to select a summer time setting.
Each press of (D) cycles through available
settings in the sequence shown below.
●
[AUTO]
The watch switches between standard
time and summer time automatically.
●
[OFF]
The watch always indicates standard
time.
●
[ON]
The watch always indicates summer
time.
6. Press (A) to complete the setting
operation.
Note
●
While the setting is being configured,
the watch will exit the setting operation
automatically after about two or three
minutes of non-operation.
●
Setting the Time/Date
1. Enter the Timekeeping Mode.
l
Navigating Between Modes
2. Hold down (A) for at least two seconds.
Release the button when the name of the
currently selected Home City appears on
the display.
Home City
3. Keep pressing (C) until the setting you
want to change is flashing.
●
Each press of (C) moves the flashing to
the next setting in the sequence shown
below.
Power Saving
Auto time adjustment
Illumination duration
Operation tone enable/disable
Day of the week language
Date display format
12/24-hour timekeeping
Day
Month
Ye a r
Minutes
Hours
Seconds
Summer time
Home City
4. Configure the date and time settings.
●
To reset the seconds to 00: Press (D).
1 is added to the minutes when the
current count is between 30 and 59
seconds.
●
For all the other settings, use (B) and (D)
to change the flashing setting.
Holding down (B) or (D) scrolls through
settings at high speed.
5. Repeat steps 3 and 4 to select time and
date settings.
6. Press (A) to complete the setting
operation.
Note
●
While the setting is being configured,
the watch will exit the setting operation
automatically after about two or three
minutes of non-operation.
●
Switching between 12-hour and 24-
hour Timekeeping
You can specify either 12-hour format or 24-
hour format for the time display.
1. Enter the Timekeeping Mode.
l
Navigating Between Modes
2. Hold down (A) for at least two seconds.
Release the button when the name of the
currently selected Home City appears on
the display.
Home City
Watch Operation Guide 3539
19

3. Press (C) eight times.
This causes [12H] or [24H] to flash on the
display.
4. Press (D) to toggle the setting between
[12H] (12-hour timekeeping) and [24H]
(24-hour timekeeping).
24-hour timekeeping12-hour timekeeping
5. Press (A) to complete the setting
operation.
Note
●
While the setting is being configured,
the watch will exit the setting operation
automatically after about two or three
minutes of non-operation.
Using the Watch in a Medical
Facility or Aircraft
Whenever you are in a hospital, on an aircraft,
or in any other location where auto time
calibration signal receive or connection with a
phone may cause problems, you can perform
the procedure below to disable such
operations. To re-enable auto time
adjustment, perform the same operation
again.
1. Enter the Timekeeping Mode.
l
Navigating Between Modes
2. Hold down (A) for at least two seconds.
Release the button when the name of the
currently selected Home City appears on
the display.
Home City
3. Press (C) 13 times.
This displays [RECEIVING].
4. Press (D) to toggle between the auto time
adjustment settings.
[OFF]: Auto time adjustment disabled.
[On]: Enable auto time adjustment.
5. Press (A) to complete the setting
operation.
World Time
You can view the current time in 39 cities (39
time zones), and UTC (Coordinated Universal
Time) time.
Using CASIO WATCHES to
Configure World Time City
Settings
If the watch is paired with a phone, you can
also use CASIO WATCHES to set the World
Time city.
l
Configuring World Time Settings
Note
●
World Time cities that can be selected
only by using CASIO WATCHES
cannot be selected using watch
operations.
Watch Operation Guide 3539
20

Checking World Time
1. Enter the World Time Mode.
l
Navigating Between Modes
Entering the World Time Mode causes a
World Time number and city name to
appear first. After that, the display will
appear as shown below.
World Time number
World Time
Home City time
●
Pressing (A) displays the city for the
displayed time.
●
To change the selected World Time
city, press (D).
World Time City Setting
You can specify up to five cities as your World
Time favorites. If you are in an area that
observes summer time, you can also enable
or disable summer time.
Note
●
The initial factory default summer time
setting for all cities is [AUTO]. In many
cases, the [AUTO] setting lets you use
the watch without switching between
summer time and standard time.
1. Enter the World Time Mode.
l
Navigating Between Modes
2. Use (D) to display the World Time number
whose setting you want to configure.
World Time number
3. Hold down (A) for at least two seconds.
This causes [WT] to flash on the display.
4. Use (B) and (D) to display the city you want
to specify as a World Time City.
●
Holding down (B) or (D) scrolls through
settings at high speed.
5. If you want to change the summer time
setting, press (C).
6. Use (D) to select a summer time setting.
●
[AUTO]
The watch switches between standard
time and summer time automatically.
●
[OFF]
The watch always indicates standard
time.
●
[ON]
The watch always indicates summer
time.
7. Press (A) to complete the setting
operation.
Note
●
While the setting is being configured,
the watch will exit the setting operation
automatically after about two or three
minutes of non-operation.
●
While [UTC] is selected as the city, you
will not be able to change or check the
summer time setting.
●
If you select a World Time City with the
CASIO WATCHES phone app and
then change to a different city with a
watch operation, the CASIO
WATCHES city information is deleted
from the watch.
l
Configuring World Time Settings
Swapping Your Home Time
and World Time
In the World Time mode, press (A) and (B) at
the same time to swap your Home City time
with your World Time.
Example: To swap your Home City (Tokyo)
with your World Time City (New York)
After swappingBefore swapping
New York time
New York time
Tokyo time
Tokyo time
Note
●
This function comes in handy when
you need to move to another time
zone. For details about how to use it,
go to the section below.
l
Moving to Another Time Zone
Watch Operation Guide 3539
21

Alarm
The watch will beep when the alarm time is
reached. You can configure up to four
standard daily alarms, and one daily alarm
with snooze. The hourly time signal causes the
watch to beep every hour on the hour.
●
Snooze causes the alarm to sound up to
seven times, at five-minute intervals.
●
The alarm sound is muted in the cases
described below.
ー
When battery power is low
ー
When watch is at Level 2 power saving
l
Power Saving Function
Using CASIO WATCHES to
Configure Alarm Settings
If the watch is paired with a phone, you can
also use CASIO WATCHES to set alarms.
l
Configuring Watch Settings
Configuring Alarm Settings
1. Enter the Alarm Mode.
l
Navigating Between Modes
2. Use (D) to display the alarm screen (alarm
number [1] to [4] or [SNZ]) whose setting
you want to change.
Alarm time
Alarm number
3. Hold down (A) for at least two seconds.
Release the button when the hours digits
start to flash.
●
While the setting is being configured,
the watch will exit the setting operation
automatically after about two or three
minutes of non-operation.
Alarm hour
4. Use (B) and (D) to change the hour setting.
●
Holding down (B) or (D) scrolls through
settings at high speed.
●
If you are using 12-hour timekeeping,
[P] indicates p.m.
5. Press (C).
This causes the minutes digits to flash.
Alarm minute
6. Use (B) and (D) to set the minute setting.
7. Press (A) to exit the setting screen.
●
(alarm) is shown on the
display while an alarm is turned on.
●
Testing the alarm
In the Alarm Mode, hold down (D) to sound the
alarm.
●
To stop the alarm
Pressing any button while the beeper is
sounding stops it.
Snooze causes the alarm to sound up to seven
times, at five-minute intervals. To cancel a
snooze alarm, turn [SNZ] off.
l
Turning Off an Alarm or the Hourly Time
Signal
Note
●
A beeper sounds for 10 seconds when
an alarm time is reached.
●
The watch will automatically return
from the Alarm Mode to the
Timekeeping Mode if you do not
perform any operation for about two or
three minutes.
Watch Operation Guide 3539
22

Enabling the Hourly Time
Signal
1. Enter the Alarm Mode.
l
Navigating Between Modes
2. Use (D) to display the hourly time signal
screen ([SIG]).
3. Press (A) to toggle the hourly time signal
between enabled and disabled.
●
(hourly time signal) is shown on
the display while the hourly time signal
is turned on.
Turning Off an Alarm or the
Hourly Time Signal
To stop an alarm or the hourly time signal from
sounding, perform the steps below to turn it
off.
●
To have an alarm or hourly time signal
sound again, turn it back on.
Note
●
Indicators are displayed while any of
the alarms or the hourly time signal is
turned on.
●
The applicable indicators are not
displayed while all of the alarms are
turned off and/or the hourly time signal
is turned off.
Snooze
Hourly time signal
Alarm
1. Enter the Alarm Mode.
l
Navigating Between Modes
2. Use (D) to scroll through the alarm ([1] to
[4], [SNZ]) and hourly time signal ([SIG])
screens until the one you want to turn off
is displayed.
Alarm number or hourly time signal
3. Press (A) to turn off the displayed alarm or
the hourly time signal.
●
Each press of (A) toggles between on
and off.
●
Turning off an alarm causes
(alarm) to disappear from the display.
Turning off the hourly time signal
causes (hourly time signal) to
disappear.
Note
●
If (alarm) is still displayed
after you turn off an alarm, it means that
at least one of the other alarms is still
turned on. To turn off all of the alarms,
repeat steps 2 and 3 until the
(alarm) indicator is no
longer displayed.
Moving to Another
Time Zone
Use the procedure below to easily change day
and time settings of the watch to a destination
location.
●
Before Boarding
1. Configure the World Time to the current
time at your destination.
Destination time
Current time
l
Using CASIO WATCHES to Configure
Settings
l
Using Watch Operations to Configure
Settings
2. Disable auto time adjustment.
l
Using the Watch in a Medical Facility or
Aircraft
Watch Operation Guide 3539
23

●
After Arriving
1. Swap the origin time zone time with the
destination time zone time.
After swappingBefore swapping
World Time
Destination
World Time
Origin
l
Using CASIO WATCHES to Configure
Settings
l
Using Watch Operations to Configure
Settings
2. Enable auto time adjustment.
l
Using the Watch in a Medical Facility or
Aircraft
3. Adjust the time setting.
l
Triggering Immediate Time Adjustment
Stopwatch
The stopwatch measures elapsed time in
1/100-second units for the first hour, and in 1-
second units after that for up to 23 hours 59
minutes 59 seconds (24 hours).
Measuring Elapsed Time
1. Enter the Stopwatch Mode.
l
Navigating Between Modes
2. Use the operations below to measure
elapsed time.
Stop
Resume
Stop
Start
●
Elapsed time is shown in 1/100-second
units for the first hour of the
measurement. After the first hour,
elapsed time is shown in one-second
units.
Hour, minute, second
After first hour
Minutes, seconds,
1/100 seconds
First hour
3. Press (A) to reset the measurement time
to all zeros.
Measuring a Split Time
1. Enter the Stopwatch Mode.
l
Navigating Between Modes
2. Use the operations below to measure
elapsed time.
●
Pressing (A) displays the elapsed time
from the start of a race up to the point
when you pressed the button (split
time).
D
A
A
D
Stop
Split release
Split
Start
●
Elapsed time is shown in 1/100-second
units for the first hour of the
measurement. After the first hour,
elapsed time is shown in one-second
units.
After first hourFirst hour
Hour, minute, secondMinutes, seconds,
1/100 seconds
3. Press (A) to reset the measurement time
to all zeros.
Watch Operation Guide 3539
24

Timing the First and Second
Place Finishers
1. Enter the Stopwatch Mode.
l
Navigating Between Modes
2. Use the operations below to measure
elapsed time.
D
A
D
2nd Finisher*
1st Finisher*
Start
* This displays the time of the first
finisher.
●
Elapsed time is shown in 1/100-second
units for the first hour of the
measurement. After the first hour,
elapsed time is shown in one-second
units.
After first hourFirst hour
Hour, minute, secondMinutes, seconds,
1/100 seconds
3. Press (A) to display the time of the second
finisher.
4. Press (A) to reset the measurement time
to all zeros.
Timer
The timer counts down from a start time
specified by you. A beeper sounds when the
end of the countdown is reached.
●
The beeper is muted when battery power is
low.
Using CASIO WATCHES to
Configure Timer Settings
If the watch is paired with a phone, you can
also use the CASIO WATCHES phone app to
set the timer start time.
l
Configuring Watch Settings
Setting the Countdown Start
Time
The countdown start time can be set in 1-
second units up to 24 hours.
●
If a timer countdown operation is in
progress, reset the timer to its current start
time before performing this operation.
l
Using the Timer
1. Enter the Timer Mode.
l
Navigating Between Modes
2. Hold down (A) for at least two seconds.
This causes the hours digits to flash.
Hours
3. Use (B) and (D) to change the timer hours
setting.
●
Holding down (B) or (D) scrolls through
settings at high speed.
4. Press (C).
This causes the minutes digits to flash.
Minutes
5. Use (B) and (D) to change the timer
minutes setting.
6. Press (C).
This causes the seconds digits to flash.
Seconds
7. Use (B) and (D) to change the seconds
setting.
8. Press (A) to exit the setting screen.
Note
●
While the setting is being configured,
the watch will exit the setting operation
automatically after about two or three
minutes of non-operation.
●
Setting a start time of [0:00 00] will
perform a countdown of 24 hours.
Watch Operation Guide 3539
25

Using the Timer
1. Enter the Timer Mode.
l
Navigating Between Modes
Hour, minute, second
2. Use the operations below to perform a
timer operation.
D
D
D
(Time up)
Resume
Pause
(Countdown starts)
Start
●
A beeper will sound for 10 seconds to
let you know when the end of a
countdown is reached.
●
You can reset a paused countdown to
its start time, by pressing (A).
3. Press any button to stop the tone.
Reminder
After you create a reminder for an
appointment, anniversary, or some other
event you don’t want to forget, the watch will
remind you when that day arrives.
Creating a Reminder
Use CASIO WATCHES to create reminders.
●
To use CASIO WATCHES, you first need to
pair your watch with a phone.
l
Getting Ready
●
If the watch is already paired with a phone,
use CASIO WATCHES to create reminders.
l
Configuring Reminder Settings
Checking Reminder
Notifications
[REM] flashes on the display during a day
when there is an anniversary or event that was
created with the CASIO WATCHES phone
app. Pressing (A) will display the title assigned
to the reminder.
After the title is displayed once, the date of the
reminder will appear with the dot between the
month and day flashing. Pressing (A) while the
dot is flashing will display the title again.
Note
●
If you turn on display illumination on a
reminder date, the display light will
flash red for a few seconds after
illumination automatically turns off.
Watch Operation Guide 3539
26

Other Settings
This section explains other watch settings you
can configure.
Changing the Date Display
Format
1. Enter the Timekeeping Mode.
l
Navigating Between Modes
2. Hold down (A) for at least two seconds.
Release the button when the name of the
currently selected Home City appears on
the display.
Home City
3. Press (C) nine times.
This displays a screen for selecting the
date display format.
4. Press (D) to select a date display format.
[M.DD]: Month, day
[DD.M]: Day, month
5. Press (A) to exit the setting screen.
Note
●
While the setting is being configured,
the watch will exit the setting operation
automatically after about two or three
minutes of non-operation.
Specifying the Day of the
Week Language
You can select any one of six languages for
the day of the week display in the Timekeeping
Mode.
1. Enter the Timekeeping Mode.
l
Navigating Between Modes
2. Hold down (A) for at least two seconds.
Release the button when the name of the
currently selected Home City appears on
the display.
Home City
3. Press (C) 10 times.
This causes the language setting to flash.
4. Use (D) to select a language.
[ENG]: English
[ESP]: Spanish
[FRA]: French
[DEU]: German
[ITA]: Italian
[PyC]: Russian
5. Press (A) to exit the setting screen.
Note
●
While the setting is being configured,
the watch will exit the setting operation
automatically after about two or three
minutes of non-operation.
Enabling the Button
Operation Tone
Use the procedure below to enable or disable
the tone that sounds when you press a button.
1. Enter the Timekeeping Mode.
l
Navigating Between Modes
2. Hold down (A) for at least two seconds.
Release the button when the name of the
currently selected Home City appears on
the display.
Home City
3. Press (C) 11 times.
This causes [KEY♪] or [MUTE] to flash on
the display.
4. Press (D) to select [KEY♪] or [MUTE].
[KEY♪]: Operation tone enabled.
[MUTE]: Operation tone muted.
5. Press (A) to exit the setting screen.
Note
●
While the setting is being configured,
the watch will exit the setting operation
automatically after about two or three
minutes of non-operation.
●
Note that alarm and timer tones will still
sound even while the operation tone is
muted.
Watch Operation Guide 3539
27

Configuring Power Saving
Function Settings
1. Enter the Timekeeping Mode.
l
Navigating Between Modes
2. Hold down (A) for at least two seconds.
Release the button when the name of the
currently selected Home City appears on
the display.
Home City
3. Press (C) 14 times.
This displays [POWER SAVING].
4. Press (D) to toggle between on and off.
[On]: Power Saving enabled.
[OFF]: Power Saving disabled.
5. Press (A) to exit the setting screen.
Note
●
While the setting is being configured,
the watch will exit the setting operation
automatically after about two or three
minutes of non-operation.
●
For details about Power Saving, refer
to the information below.
l
Power Saving Function
Resetting Watch Settings
This section explains how to return the watch
settings below to their initial factory defaults.
●
Watch Settings
●
Reminder
●
Stopwatch
●
Timer
●
Alarm
1. Enter the Timekeeping Mode.
l
Navigating Between Modes
2. Hold down (A) for at least two seconds.
Release the button when the name of the
currently selected Home City appears on
the display.
Home City
3. Press (C) twice.
This causes the seconds to flash.
Seconds
4. Hold down (B) for at least seven seconds.
Release the button when [ALL] stops
flashing.
Note
●
While the setting is being configured,
the watch will exit the setting operation
automatically after about two or three
minutes of non-operation.
●
Resetting the watch will also delete
information for pairing the watch with a
phone, and unpair them.
Other Information
This section provides non-operational
information you also need to know. Refer to
this information as required.
City Table
City Offset
UTC
Coordinated
Universal Time
0
LONDON * London
PARIS * Paris +1
ATHENS * Athens +2
JEDDAH Jeddah +3
TEHRAN Tehran +3.5
DUBAI Dubai +4
KABUL Kabul +4.5
KARACHI Karachi +5
DELHI Delhi +5.5
KATHMANDU Kathmandu +5.75
DHAKA Dhaka +6
YANGON Yangon +6.5
BANGKOK Bangkok +7
HONG KONG * Hong Kong +8
PYONGYANG ** Pyongyang +8.5
EUCLA Eucla +8.75
TOKYO * Tokyo +9
ADELAIDE Adelaide +9.5
SYDNEY Sydney +10
LORD HOWE
ISLAND
Lord Howe
Island
+10.5
NOUMEA Noumea +11
WELLINGTON Wellington +12
CHATHAM
ISLANDS
Chatham
Islands
+12.75
NUKU’ALOFA Nuku’alofa +13
KIRITIMATI Kiritimati +14
BAKER ISLAND Baker Island -12
PAGO PAGO Pago Pago -11
HONOLULU Honolulu -10
MARQUESAS
ISLANDS
Marquesas
Islands
-9.5
ANCHORAGE Anchorage -9
LOS ANGELES * Los Angeles -8
DENVER * Denver -7
CHICAGO * Chicago -6
NEW YORK * New York -5
HALIFAX * Halifax -4
ST. JOHN’S St. John’s -3.5
RIO DE JANEIRO Rio de Janeiro -3
F. DE NORONHA
Fernando de
Noronha
-2
PRAIA Praia -1
Watch Operation Guide 3539
28

* Cities where time calibration signal reception
is possible.
** In May 2018, the offset for PYONGYANG
was changed to +9. However, this watch does
not reflect that change. Because of this,
selecting PYONGYANG will set an offset of
+8.5.
●
The information in the above table is current
as of July 2022.
●
Time zones may change and UTC
differentials may become different from
those shown in the table above. If this
happens, connect the watch with a phone
to update the watch with the latest time zone
information.
Summer Time Table
When [AUTO] is selected for a city that
observes summer time, switching between
standard time and summer time will be
performed automatically at the timing shown
in the table below.
Note
●
Summer time start and end dates for
your current location may be different
from those shown below. If this
happens, you can have new summer
time information for your Home City
and World Time City sent to the watch
by connecting the watch with a phone.
If the watch is not connected with a
phone, you can change the summer
time setting manually.
City Name
Summer Time
Start
Summer Time
End
London
01:00, last
Sunday in March
02:00, last
Sunday in
October
Paris
02:00, last
Sunday in March
03:00, last
Sunday in
October
Athens
03:00, last
Sunday in March
04:00, last
Sunday in
October
Tehran
00:00, March 22
or 21
00:00,
September 22 or
21
Sydney,
Adelaide
02:00, first
Sunday in
October
03:00, first
Sunday in April
Lord Howe
Island
02:00, first
Sunday in
October
02:00, first
Sunday in April
Wellington
02:00, last
Sunday in
September
03:00, first
Sunday in April
Chatham
Islands
02:45, last
Sunday in
September
03:45, first
Sunday in April
Anchorage
02:00, second
Sunday in March
02:00, first
Sunday in
November
Los
Angeles
02:00, second
Sunday in March
02:00, first
Sunday in
November
Denver
02:00, second
Sunday in March
02:00, first
Sunday in
November
Chicago
02:00, second
Sunday in March
02:00, first
Sunday in
November
New York
02:00, second
Sunday in March
02:00, first
Sunday in
November
Halifax
02:00, second
Sunday in March
02:00, first
Sunday in
November
St. John’s
02:00, second
Sunday in March
02:00, first
Sunday in
November
●
The information in the above table is current
as of July 2022.
Supported Phones
For information about phones that can
connect with the watch, visit the CASIO
website.
https://world.casio.com/os_mobile/wat/
Specifications
Accuracy at normal temperature :
±15 seconds per month average when time
adjustment by time calibration signal
reception or by communication with a
phone is not possible.
Timekeeping :
Hour, minute, second, year, month, day,
day of the week
a.m./p.m.(P)/24-hour timekeeping
Full Auto Calendar (2000 to 2099) *
* Year display on setting screen only.
Signal Receive Functions :
Auto receive, manual receive
Auto summer time switching
Auto transmitter selection (for JJY, MSF/
DCF77)
Receivable call signs:
JJY (40 kHz/60 kHz), WWVB (60 kHz), MSF
(60 kHz), DCF77 (77.5 kHz), BPC (68.5
kHz)
OFF: Signal receive disabled
World Time :
Current time in 39 cities (39 time zones) and
for UTC, auto summer time switching
Home City/World Time City swapping
Alarm :
Time alarm
Alarms: 5 (with one snooze alarm)
Setting units: Hours, minutes
Beeper: 10 seconds
Hourly time signal
Beeps every hour on the hour
Stopwatch :
Measurement unit: 1/100 seconds (first
hour); 1 second (after first hour)
Measurement range: 23 hours, 59 minutes,
59 seconds (24 hours)
Measurement functions: Elapsed time, split
time, two finishes
Watch Operation Guide 3539
29

Timer :
Measuring unit: 1 second
Countdown range: 24 hours
Setting unit: 1 second
Time up: 10-second beeper
Mobile Link :
Auto Time Adjustment
Time setting adjusted automatically at
preset time
One-touch Time Correction
Manual connection and time adjustment
Phone finder
Watch operation sounds the alert sound
of the mobile phone
World Time
Current time for approximately 300 cities
selected for the watch
Home Time/World Time swapping
Original city function (location and name
settings)
Auto Summer Time Switching
Automatic switching between standard
time and summer time
Timer Settings
Alarm Settings
Reminder
Reminds you of anniversaries and other
important dates.
Data Communication Specifications
Bluetooth
®
Frequency Band: 2400MHz to 2480MHz
Maximum Transmission: 0 dBm (1 mW)
Communication range: Up to 2 meters
(depends on environment)
Other :
LED backlight light (Super Illuminator,
afterglow with selectable 2 or 4-second
duration), Full Auto light, Power Saving,
operation tone enable/disable, selectable
date format, selectable day of the week
language, auto time adjustment enable/
disable
Power Supply :
Solar panel and one rechargeable battery
Battery operating time: Approximately 10
months
Conditions:
Not exposed to light under the conditions
below.
Auto time adjust by smartphone: 4 times/
day
Alarm: Once (10 seconds)/day
Illumination: Once (2 seconds)/day
Power Saving: 6 hours/day
Specifications are subject to change without
notice.
Copyrights and Registered
Copyrights
●
The Bluetooth
®
word mark and logos are
registered trademarks owned by the
Bluetooth SIG, Inc. and any use of such
marks by CASIO Computer Co., Ltd. is
under license.
●
iPhone and App Store are trademarks of
Apple Inc. in the United States and other
countries.
●
iOS is a trademark or registered trademark
of Cisco Systems, Inc.
●
Android and Google Play
TM
are trademarks
or registered trademarks of Google LLC.
●
Other company names and product names
used herein are trademarks or registered
trademarks of their respective companies.
Troubleshooting
Signal Reception (Time
Calibration Signal)
Q1
The watch cannot perform a receive
operation.
Is the watch’s battery charged?
Signal reception is not possible while
battery power is low. Keep the watch
exposed to light until it recharges
sufficiently.
l
Charging
Is the watch in the Timekeeping Mode?
Time signal receive is performed only
while the watch is in the Timekeeping
Mode. Return to the Timekeeping Mode.
l
Navigating Between Modes
Is your Home City setting correct for your
location?
The watch will not indicate the correct time
if the Home City setting is wrong. Change
your Home City setting so it correctly
reflects your location.
l
Setting a Home City
Is the watch connected with a phone?
Auto receive of signals by the watch is
disabled while it is connected with a
phone.
l
Time Adjustment Using a Time Signal
After checking the above, the watch still
cannot perform a receive operation.
Time calibration signal reception is not
possible under the conditions described
below.
●
When watch is at Level 2 power saving
●
Timer countdown operation in progress
If successful reception is not possible for
some reason, you can adjust the time and
day settings manually.
Watch Operation Guide 3539
30

Q2
The signal receive operation always
fails.
Is the watch in a location that is appropriate
for signal reception?
Check your surroundings and move the
watch to a location where signal reception
is better.
l
Appropriate Signal Reception Location
Did you avoid touching the watch while the
receive operation was in progress?
Minimize movement of the watch and do
not perform any watch operation while a
receive operation is in progress.
Is there an alarm configured to sound
during the same period that the signal
receive operation is performed?
Receive stops if an alarm operation starts
while it is being performed. Disable the
alarm.
l
Turning Off an Alarm or the Hourly
Time Signal
Is the signal transmitter in your area
transmitting a signal?
The transmitter of the time calibration may
not be transmitting a signal.
Try again later.
Q3
Signal reception should have been
successful, but the watch’s time and/
or day is wrong.
Adjust time and day settings manually.
l
Using Watch Operations to Adjust the Time
Setting
I can’t pair the watch with a
phone.
Q1
I’ve never been able to establish a
(pairing) connection between the
watch and phone.
Are you using a supported phone model?
Check if the phone model and its
operating system are supported by the
watch.
For information about supported phone
models, visit the CASIO Website.
https://world.casio.com/os_mobile/wat/
Did you install the CASIO WATCHES
phone app on your phone?
The CASIO WATCHES phone app needs
to be installed on your phone in order to
connect with the watch.
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A
Install the app on your phone.
Are your phone’s Bluetooth settings
configured correctly?
Configure the phone’s Bluetooth settings.
For details about setting procedures, see
your phone documentation.
iPhone Users
●
“Settings”
n
“Bluetooth”
n
On
●
“Settings”
n
“Privacy”
n
“Bluetooth”
n
“CASIO WATCHES”
n
On
Android Users
●
Enable Bluetooth.
Other than the above.
Some phones need to have BT Smart
disabled to use CASIO WATCHES. For
details about setting procedures, see your
phone documentation.
On the Home Screen, tap: “Menu”
n
“Settings”
n
“Bluetooth”
n
“Menu”
n
“BT Smart settings”
n
“Disable”.
I can’t reconnect the watch
and phone.
Q1
The watch will not re-connect with the
phone after they are disconnected.
Is the CASIO WATCHES phone app
running?
The watch cannot re-connect with your
phone unless CASIO WATCHES is
running on the phone. On your phone’s
Home Screen, tap the “CASIO
WATCHES” icon. Next, on the watch, hold
down (C) for at least three seconds.
Have you tried turning your phone off and
then back on again?
Turn your phone off and then back on, and
then tap the “CASIO WATCHES” icon.
Next, on the watch, hold down (C) for at
least three seconds.
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Q2
I can’t connect while my phone is in
the Airplane Mode.
Connection with the watch is not possible
while the phone’s Airplane Mode is enabled.
After disabling the phone’s Airplane Mode, go
to the phone’s Home Screen and tap the
“CASIO WATCHES” icon. Next, on the watch,
hold down (C) for at least three seconds.
Q3
I changed the phone’s Bluetooth
from enabled to disabled, and now I
can’t connect anymore.
On your phone, re-enable Bluetooth, and then
go to the Home Screen and tap the “CASIO
WATCHES” icon. Next, on the watch, hold
down (C) for at least three seconds.
Q4
I can’t connect after turning off the
phone.
Turn your phone off and then back on, and
then tap the “CASIO WATCHES” icon. Next,
on the watch, hold down (C) for at least three
seconds.
Phone-Watch Connection
Q1
I can’t establish a connection
between the phone and watch.
Have you tried turning your phone off and
then back on again?
Turn your phone off and then back on, and
then tap the “CASIO WATCHES” icon.
Next, on the watch, hold down (C) for at
least three seconds.
Has the watch been re-paired with the
phone?
Delete the pairing information from the
CASIO WATCHES phone app and your
phone (iPhone only), and then re-pair
them.
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Deleting Pairing Information from the
CASIO WATCHES phone app
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C
Pair the watch with a phone.
If you are unable to establish a
connection...
After deleting pairing information from the
watch, re-pair it with your phone.
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Deleting Pairing Information from the
Watch
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C
Pair the watch with a phone.
Changing to a Different
Phone Model
Q1
Connecting the current watch to
another phone.
Delete the pairing information from your watch
and then pair it with the phone you want to
connect with.
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If you purchase another phone
Auto Time Adjustment by
Bluetooth Connection (Time
Adjustment)
Q1
When does the watch adjust its time?
The watch will connect with the phone and
perform auto time adjustment at around 12:30
a.m., 6:30 a.m., 12:30 p.m. and 6:30 p.m. The
connection is automatically terminated after
auto time adjustment is complete.
Q2
Auto time adjustment is not
performed at a scheduled time.
Is auto time adjustment not being
performed according to its normal
schedule?
Note that auto time adjustment is not
performed for 24 hours after swapping of
the Home Time and World Time, or after
the time setting is adjusted manually on
the watch. Auto time adjustment will
resume 24 hours after either of the above
operations is performed.
Is a timer countdown operation in
progress?
Auto time adjustment will not start at the
scheduled times if a timer countdown
operation is in progress. Stop the timer
countdown operation.
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Using the Timer
Is auto time adjustment enabled?
Auto time adjustment will not be
performed at the scheduled times unless
it is enabled. Enable auto time
adjustment.
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Using the Watch in a Medical Facility or
Aircraft
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Q3
The watch does not connect with a
phone and adjust its time when I
press (D).
The watch will not adjust its time if you press
(D) while a timer countdown operation is in
progress. Stop the timer countdown operation
and then press (D) again.
Q4
Time is not displayed correctly.
If your phone is unable to receive a signal
because you are outside its service range or
for some other reason, the watch may not be
able to display the correct time. If this
happens, connect the phone to its network
and then adjust the time setting.
Alarm and Hourly Time
Signal
Q1
An alarm does not sound.
Is the watch’s battery charged?
Keep the watch exposed to light until it
recharges sufficiently.
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Charging
Other than the above.
The alarm’s settings may not be
configured. Configure the alarm settings.
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Configuring Alarm Settings
Q2
The hourly time signal does not
sound.
Is the watch’s battery charged?
Keep the watch exposed to light until it
recharges sufficiently.
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Charging
Other than the above.
The hourly time signal may be disabled.
Enable the hourly time signal.
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Enabling the Hourly Time Signal
Charging
Q1
The watch does not work even
though it is exposed to light.
The watch stops operating whenever the
battery goes dead. Keep the watch exposed
to light until it recharges sufficiently.
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Dead Battery
Q2
[R] is flashing on the digital display.
The watch is in the charge recovery mode.
Wait until the recovery process is complete
(about 15 minutes). The watch will recover
more quickly if you place it in a brightly lit
location.
●
If an alarm, hourly time signal, illumination
and/or other power-intensive functions are
used within a short period of time, the
charging capacity of the battery will drop
and cause the watch to go into a charge
recovery mode. Function availability will be
temporarily limited, but functionality will
return after the battery recovers.
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Dead Battery
Q3
[CHG] is flashing on the display.
The charge level of the watch is extremely low.
Immediately expose the watch to light to
charge it.
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Low Battery
Other
Q1
I can’t find the information I need
here.
Visit the website below.
https://world.casio.com/support/
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