Troubleshooting
Charging with the Charger
Q1The watch won’t charge with the charger.
Is the watch securely attached to the charger?
Charging may fail if there is space between the charger and watch.
Did you leave the watch attached to the charger after charging was complete?
Charging stops automatically after the watch becomes fully charged. If you want to charge again, remove the watch from and then re-attach it to the charger.
Is charging still impossible after checking the above points?
Check to make sure that the USB device or power source is functioning normally.
Q2Charging stops before it is complete.
Charging may stop if some temporary abnormality occurs. Unplug the USB cable from the charger and check for abnormalities. If there is nothing wrong, try charging again.
If the above does not eliminate the problem, contact your original retailer or a CASIO service center.
Signal Reception (GPS)
Q1The watch cannot perform a GPS signal receive operation.
Is the watch’s battery charged?
GPS signal reception is not possible while the battery indicator is 
or lower. Charge the watch.
Is the watch in the Timekeeping Mode?
GPS signal reception is not possible unless the watch is in the Timekeeping Mode. Signal reception is also disabled in the Airplane Mode. Return to the Timekeeping Mode.
After checking the above, the watch still cannot perform a GPS signal receive operation.
GPS signal reception is not possible under the conditions described below.
- During power saving
- Timer countdown operation in progress
Q2The watch is not receiving time information.
The watch will not perform auto GPS signal receive while there is a connection between it an a phone. If you want to receive GPS signals in this case, perform manual receive.
Q3A screen showing that a receive operation is in progress has been on the display for a long time.
The watch may be receiving leap second information.
Q4The GPS 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 GPS signal reception is better.
Is the LCD of the watch pointed straight up at the sky?
Minimize movement of the watch while the receive operation is in progress.
When the watch is set up for auto receive, take care to avoid covering its LCD with the sleeve of your clothing.
An alarm started sounding while the receive operation was in progress.
Receive stops if an alarm operation starts while it is being performed. Disable the alarm.
Q5Signal reception should have been successful, but the watch’s time and/or day is wrong.
Is your Home City (time zone) setting correct for your location?
Change your Home City (time zone) setting so it correctly indicates your location.
After checking the above, the time and/or day settings is still wrong.
Adjust time and day settings manually.
I can’t pair the watch with a phone.
Q1I’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.
Did you install CASIO WATCHES on your phone?
CASIO WATCHES needs to be installed on your phone in order to connect with the watch.
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”
“Bluetooth” On
- “Settings” “Privacy” “Bluetooth Sharing” “CASIO WATCHES” 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” “Settings” “Bluetooth” “Menu” “BT Smart settings” “Disable”.
I can’t reconnect the watch and phone.
Q1The watch will not re-connect with the phone after they are disconnected.
Is CASIO WATCHES running?
The watch cannot re-connect with the phone unless CASIO WATCHES is running on the phone. On the phone’s Home Screen, tap the CASIO WATCHES icon. Then on the watch, hold down (C) for about 2.5 seconds to enter the Communication Mode.
Have you tried turning your phone off and then back on again?
On the phone, turn power off and then back on, and then tap the CASIO WATCHES icon. Next, on the watch, hold down (C) for about 2.5 seconds to enter the Communication Mode.
Q2I can’t connect while my phone is in the Airplane Mode.
Connection with the watch is not possible while the phone is in the Airplane Mode. On the phone, exit the Airplane Mode, and then go to the Home Screen and tap the “CASIO WATCHES” icon. Next, on the watch, hold down (C) for about 2.5 seconds to enter the Communication Mode.
Q3I can’t connect while the watch is in the Airplane Mode.
On the watch, exit the Airplane Mode. Next, on the watch, hold down (C) for about 2.5 seconds to enter the Communication Mode.
Q4I changed the phone’s Bluetooth from enabled to disabled, and now I can’t connect anymore.
On the phone, disable and then re-enable Bluetooth, and then go to the Home Screen and tap the “CASIO WATCHES” icon. Next, on the watch, hold down (C) for about 2.5 seconds to enter the Communication Mode.
Q5I can’t connect after turning off the phone.
On the phone, turn on power and then tap the CASIO WATCHES icon. Next, on the watch, hold down (C) for about 2.5 seconds to enter the Communication Mode.
Phone-Watch Connection
Q1I can’t establish a connection between the phone and watch.
Have you tried turning your phone off and then back on again?
On the phone, turn power off and then back on, and then tap the CASIO WATCHES icon. Next, on the watch, hold down (C) for about 2.5 seconds to enter the Communication Mode.
Has the watch been re-paired with the phone?
After unpairing the watch and phone, re-pair them again.
If you are unable to establish a connection...
Use the procedure below to delete the pairing information from the watch, and then re-pair the watch and phone.
Hold down (C) for about one second to enter the Timekeeping Mode.
Press (A) to display the setting screen.
Rotate the rotary switch to move the pointer to [UNPAIRING].
Press the rotary switch.
Rotate the rotary switch to move the pointer to [YES].
Press the rotary switch to delete pairing information.
Press (C) to exit the setting screen.
Changing to a Different Phone Model
Q1Connecting the current watch to another phone.
Pair the watch with the phone.
Auto Time Adjustment by Bluetooth Connection (Time Adjustment)
Q1When does the watch adjust is 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. Also, GPS 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.
Q2Auto time adjustment is performed, but the time setting is not correct.
Is auto time adjustment not being performed according to its normal schedule?
Note that auto time adjustment is not performed for 24 hours after the time setting is adjusted manually on the watch. Auto time adjustment will resume after 24 hours.
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.
Is the watch in the Airplane Mode?
Auto time adjustment will not be performed at the scheduled times if the watch is in the Airplane Mode. Exit the watch’s Airplane Mode.
Q3The watch does not synchronize its time setting with a phone even though I follow the steps under Triggering Immediate Time Adjustment.
The watch will not start time adjustment while a timer countdown operation is in progress. Wait until the timer countdown operation is complete and then perform the operation again.
Q4Time is not displayed correctly.
The phone’s time setting may be incorrect because it is unable to connect with its network due to being out of range, etc. If this happens, connect the phone to its network and then adjust the time setting.
Navigation
Q1The watch won’t enter the GPS Navigation Mode.
Is the watch being charged with the charger?
The GPS Navigation Mode cannot be used while the watch is being charged with the charger. Remove the watch from the charger.
Is the battery charge level sufficient?
The GPS function can be used only when the battery indicator shows 
or higher. If the battery charge level is too low, charge the watch.
Altitude Measurement
Q1Readings produce different results at the same location.
Watch readings are different from altitude information available from other sources.
Correct altitude readings are not possible.
Relative altitude is calculated based on changes in barometric pressure measured by the watch’s pressure sensor. This means that barometric pressure changes can cause readings taken at the same location to be different. Also note that the value displayed by the watch may be different from the actual elevation and/or sea level elevation indicated for the area where you are located. When using the watch’s altimeter while mountain climbing, it is recommended that you regularly calibrate its readings in accordance with local altitude (elevation) indications.
Q2[-----] appears on the display following altitude differential measurement.
[-----] appears when the altitude differential is outside the allowable measuring range (±3,000 m). If [ERROR] appears on the display, there may be a problem with the sensor.
Q3[ERROR] appears during measurement.
There may be a problem with the sensor. Try taking another measurement. If [ERROR] keeps appearing after multiple measurement attempts, contact a CASIO service center.
Digital Compass
Q1The symbol 
is shown on the display.
Abnormal magnetism has been detected. Move away from any potential source of strong magnetism and try taking a reading again.
- If appears again, it could mean that the watch body has become magnetized. Move away from any potential source of strong magnetism, perform direction calibration, and then try taking a reading again.
Q2[ERROR] appears during measurement.
There is a problem with the sensor or there may be a source strong magnetic force nearby. Move away from any potential source of strong magnetism and try taking a reading again. If [ERROR] keeps appearing after multiple measurement attempts, contact a CASIO service center.
Q3[ERROR] appears on the display following direction calibration.
If [- - -] is followed by [ERROR] on the display, it could mean there is something wrong with the sensor.
- If [ERROR] disappears after about one second, try performing bidirectional calibration again.
- If [ERROR] continues to appear even after multiple attempts, contact a CASIO service center.
Q4Direction information indicated by the watch is different from that indicated by a backup compass.
Move away from any potential source of strong magnetism, perform bidirectional calibration, and then try taking a reading again.
Q5Readings at the same location produce different results.
Cannot take readings indoors.
Move away from any potential source of strong magnetism and try taking a reading again.
Barometric Pressure Measurement
Q1[ERROR] appears during measurement.
There may be a problem with the sensor. Try taking another measurement. If [ERROR] keeps appearing after multiple measurement attempts, contact a CASIO service center.
Temperature Measurement
Q1[ERROR] appears during measurement.
There may be a problem with the sensor. Try taking another measurement. If [ERROR] keeps appearing after multiple measurement attempts, contact a CASIO service center.
Alarms
Q1The alarm does not sound.
Is the watch’s battery charged?
Charge the watch until the battery is sufficiently recharged.
Is the alarm enabled?
Enable the alarm.
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