Casio OCW-110TDJ Troubleshooting guide

OCW-110TDJOCW-100TDJ
SERVICE MANUAL
& PARTS LIST
(WITHOUT PRICE)
QW-3721
MODULE NO.
REF. NO. S/M-920
OCT. 2005
Ver.1 : Jun. 2010

CONTENTS
Page
1. SPECIFICATIONS: MODULE QW-3721 .................................................... 1
2. OPERATION CHART: MODULE QW-3721 ............................................... 2
3. DRAWINGS: MODULE QW-3721
3-1. CIRCUIT DIAGRAM ...................................................................................... 8
3-2. CHECKING TERMINALS AND COMPONENTS ..........................................9
4. EXPLODED VIEW: MODULE QW-3721 ................................................... 10
5. PARTS LIST: MODULE QW-3721 ............................................................ 11
6. PRECAUTIONS FOR REPAIR: MODULE QW-3721
6-1. AC (ALL CLEAR) AND REMOVING OF MODULE ..................................... 12
6-2. ACCURACY CHECKING .............................................................................12
6-3. SOLAR CELL-PCB ASS'Y CONTACT CHECKING....................................13
6-4. TIME CALIBRATION SIGNAL TEST MODE ...............................................13
6-5. SECOND HAND MOVEMENT ACCURACY CHECK MODE ......................13
7. TROUBLESHOOTING: MODULE QW-3721.............................................14

— 1 —
1. SPECIFICATIONS: MODULE QW-3721
Battery CTL1025 (Storage battery)
Note: Use CTL1025 only. Other storage battery or CR1025 can cause
damage to the watch.
Battery life Approx. 4 months
Current consumption 0.53 µA maximum: Follow the procedure described below to measure the
current consumption. Energize while pressing the Bbutton.
Release energizing after releasing the Bbutton.
Alarm system Piezo plate on Cover/Back
Accuracy ±20 sec./month
Accuracy setting system Chip capacitor selection
Accuracy checking See page 12
Functions • Solar powered
• Time calibration signal reception
Auto receive
Manual receive
• Time Calibration Signal
Receivable Time Calibration Signals
Fukushima, Japan (Call Sign: JJY, Frequency: 40kHz)
Fukuoka/Saga, Japan (Call Sign: JJY, Frequency: 60kHz)
• Low battery warning display
• Auto-calendar
• Regular timekeeping:
Analog: 3 hands (Hour, minutes, seconds)
• LED light (with full auto light function)
• Daily alarms
Item Detail

— 2 —
2. OPERATION CHART: MODULE QW-3721
Each press of the BB
BB
Bbutton sounds a confirmation tone and cycles through available modes in the sequence shown below.
The watch will revert to the Timekeeping Mode automatically if you leave it in any other mode without performing any operation for about two
or three minutes.
(Mode Change)
(Light)
Minute Hand
Second Hand
Hour Hand
Date
Timekeeping Mode
If the time setting is not correct... Normally, you should never need to adjust the time setting of the watch as long as it is able to receive a time calibration signal. If signal reception is impossible for some reason, use the procedures under “Adjusting the Home Positions”to check the home positions of the hands, and make adjustments as required.
Button
Button
Receive Successful
OFF
ON
Receive Failed
Use this mode to adjust the home positions of the analog hands. The home positions of the hands are correct when they point to 12 o’clock.
Use this mode to set the alarm time and to turn the alarm on or off. The second hand will move to either “ON”or “OFF”.
Use this mode to check if signal reception is being performed normally. The second hand will move to either “GET”or “NG”.
Receive Result Mode Alarm Mode
Home Position Adjustment Mode
Modes and Hand Movement
Charging Precautions
Avoid charging the watch in the following locations, and anywhere else where the watch may become very hot.
On the dashboard of an automobile parked in the sun Very close to an incandescent light source or other sources of
heat
In a location exposed to direct sunlight for long periods
Depending on the light source you are using, the case of the watch may become quite hot during charging. Take care to guard against burn injury after charging.
To charge the battery
Point the solar cell (face) of the watch at a light source to charge the battery.
Remember that even a partial blockage of the solar cell reduces
charging efficiency.
Example: Positioning the watch
Solar Cell
The illustration shows the resin band model.
Charging Guide
Starting from a full charge, the watch should be able to continue operating for about four months without further charging under the conditions described below.
Daily Use
Illumination: 1.5 second Alarm: 10 seconds Signal reception: 1
Making sure the watch is regularly exposed to light ensures stable operation.
Charge Times Required to Advance to a Higher Level
Exposure Level
(Brightness)
Outdoor Sunlight
(50,000 lux)
Sunlight Through a
Window (10,000 lux)
Daylight Through a Window on
an Overcast Day (5,000 lux)
Indoor Fluorescent
Lighting (500 lux)
Approximate Exposure Time
Timekeeping Restored
Full Charge
––– –––
1 hour
2 hours 3 hours
30 hours
12 hours 61 hours
Note that the above charging times are for reference only. Actual
charging time depends on a variety of environmental factors.
The power supply of this watch uses a solar cell to generate electrical power, which is stored by a rechargeable battery. Using or storing the watch where it is not regularly exposed to light, or allowing it to be blocked from light by your sleeve for long periods as you are wearing it can cause the power of the rechargeable battery to run down. •
• •
•
• • •
• •
•
•
•
•
A low battery can cause timekeeping to stop, and can also cause time and alarm settings to be lost. Face illumination or alarm operation can cause hand movement to stop due to the sudden temporary drop in battery power. This does not
indicate malfunction, and normal operation will resume when the watch is exposed to light. Though hand movement stops, timekeeping continues internally, and the hands will be adjusted to the correct setting when normal operation returns.
Checking the Battery Level
Low battery power is indicated when the the second hand starts to jump at two-second intervals.
Jumps two seconds1-second movement Indicates date home position.
Normal Low Power Alert Timekeeping Disabled
Battery level drops due to insufficient charging.
Battery level drops further due to insufficient charging.
Hands stop at 12 o’clock.
If 2-second hand movement is being performed when the current time reaches midnight, the date indicator will change to the home position indicator ( ). If battery power drops to the next lower level, and the hands will stop at 12 o’clock.
Even after the battery drops to the level that timekeeping becomes disabled, you will be able to resume normal operation by charging the
battery.
After timekeeping becomes disabled, the hands will move to the current time after the battery is recharged sufficiently.
Keep the watch exposed to light until normal operation returns.
The following operations are disabled during 2-second hand movement. • • •
Auto and manual calibration signal reception Face illumination Alarm
Power Supply To ensure stable operation, be sure to allow the watch to be exposed to light as
much as possible.
Required Daily Charging Time
The following is the daily
amount of charging required each day to support the operations under “Daily Use”.
Exposure Level
(Brightness)
Outdoor Sunlight
(50,000 lux) 6 minutes
30 minutes 48 minutes
8 hours
Sunlight Through a
Window (10,000 lux)
Daylight Through
a Window on an
Overcast Day
(5,000 lux)
Indoor Fluorescent
Lighting (500 lux)
Approximate
Exposure
Time
■
■■
• • ■
• •
Important!

—3 —
Positioning Your Arm Correctly •You should be wearing the watch on the outside of your wrist
when using the auto light switch.
•Make sure that the left (9 o’clock) and
right (3 o’clock) sides of the watch are within ±15 degrees of being parallel with the ground. The auto light switch may not operate properly if the angle is greater.
Important! •The light may be difficult to see if you turn it on under bright
sunlight.
•If you press the Bbutton or if an alarm operation starts while the
face is illuminated, illumination will turn off.
Auto Light Precautions •Frequent use of the auto light can run down the battery. •The auto light switch may cause the face to illuminate when your
sleeve covers the face of the watch.
•The face may not illuminate immediately when you angle the
watch towards your face. This does not indicate malfunction.
•The face remains illuminated for 1.5 seconds only, even if you
leave the watch angled towards your face.
•The auto light switch is disabled automatically during 2-second
hand movement.
•The face may illuminate unintentionally when you wear the watch
on the inside of your wrist, when you shake your arm, or when you raise your arm. Be sure to turn off the auto light switch whenever you do not need face illumination.
•Keep the auto light switch turned off whenever you are wearing
the watch on the inside of your wrist.
•Electro-static charge and magnetism can interfere with auto light
operation and even make operation impossible. If this happens lower your arm to the starting position and then raise it again. If you still have trouble with illumination, try lowering your arm down to your side and then raise it to your face for reading.
Rotate your arm so the watch is angled at about 40 degrees, so you can read its face.
With the watch on your wrist, position it level with the ground.
11 11
122
22
2
At least 40 degrees
An LED light is used to illuminate the face of the watch for easy reading in the dark. An auto light switch automatically illuminates the face when you angle the watch towards your eyes for reading.
To illuminate the face manually
In the Timekeeping Mode, press the AA
AA
Abutton.
•
•
•
This illuminates the face for about 1.5 seconds.
Pressing the Abutton illuminates the display regardless of
whether the auto light switch is on or off.
You may hear a faint rattling sound when you move the watch around. This sound is caused by the movement of a metal bulb that controls operation of the auto light switch, and does not indicate malfunction.
To illuminate the face with the auto light switch
The auto light switch automatically illuminates the face whenever you angle the watch towards your eyes for reading, but only when it is dark.
The auto light switch does not illuminate the face when surrounding light is bright.
The auto light switch will illuminate the face for about 1.5 seconds in any mode.
To turn the auto light switch on and off
In the Receive Result Mode, hold down the Abutton for about three seconds to toggle the auto light switch on and off.
Face Illumination
Location Reception is difficult and may even be impossible in the locations described below. Avoid such locations when performing signal reception. •You should think of your watch operating like a radio or TV when it
is receiving the calibration signal.
If you are experiencing problems with reception, move away from the types of locations described above to a location with better reception, and try again.
Reception Range This watch is designed to receive either the Mt. Otakadoya signal (40kHz) or the Mt. Hagane signal (60kHz), whichever is strongest.
1000km
Mt. Hagane
(60kHz)
Mt. Otakadoya
(40kHz)
500km
1000km
500km
Transmitter Locations
•Under optimum conditions, the calibration signal should be
receivable up to 1,000 kilometers from the transmitter. Note that the wave is relatively weak at distances greater than 500km, so reception may be poor at long distances.
•Geographic contours, nearby buildings, seasonal conditions, the
time of day, can even make reception impossible even when you are within the range of the transmitter.
•Reception is best at night.
What is a radio-controlled watch? Your radio-controlled watch is designed to receive a time calibration signal that contains standard time data, and adjust its current time setting accordingly.
Signal data
Transmitter
Internally
Decode
Watch
Time data
Long-wave time calibration signal
Cesium
atomic clock
Signal is received using built-in antenna.
Watch decodes received data and converts it to time data.
Time is adjusted according to time data.
After the watch receives the Standard Time signal, it performs internal calculations to determine the current time. Because of this, there may be an error of up to one second in the displayed time.
Calibration Signal •The Japanese calibration signal (Call Sign: JJY) is maintained by
the National Institute of Information and Communications Technology (NICT). It is a long wave signal transmitted 24 hours a day from the Mt. Otakadoya transmitter (40kHz) located in Tamura-gun, Fukushima Prefecture, and from the Mt. Hagane transmitter (60kHz) located on the border between Saga Prefecture and Fukuoka Prefecture.
Note that transmission of the time calibration signal may be interrupted occasionally due to maintenance, lightning, etc.
How a Radio-controlled Watch Works
Near high-voltage lines
Among or near buildings
Inside a vehicle
(automobile, train, plane, etc.)
In a location where there is radio interference (construction site, airport, etc.)
Next to a household appliance or office equipment (TV, speaker, fax, computer, cell phone, etc.)
Near mountains
■
■ ■

—4 —
To check the result of the last signal receive operation
In the Timekeeping Mode, press the BB
BB
Bbutton. This enters
the Receive Result Mode.
•If the watch was able to perform a successful signal receive
operation since midnight, the second hand will move to GET. If the watch has been unable to receive any signal successfully, the second hand will move to NG.
•To return to the Timekeeping Mode, press the Bbutton three
times.
•
• • • • • •
The watch will also return to the Timekeeping Mode if you do not perform any operation for about two or three minutes.
GET
NG
The current receive result is cleared each day at midnight. This means GET indicates successful signal reception since the start of the current day. •GET continues to be indicated even if an attempt at manual
receive fails after auto receive is successful.
Calibration Signal Reception Precautions
Auto reception can be performed while the watch is in the
Timekeeping Mode only.
If the hands become misaligned for some reason, they may not
indicate the correct time, even if the time calibration signal is received normally. If this happens, use the procedure under “Adjusting the Home Positions”to adjust the home positions of the hands and the date.
Pressing any button while auto reception is in progress will cause
the watch to beep and signal reception to stop.
Make sure you are within the range of the calibration signal
transmitter before performing the reception operation. Remember that geographic contours, nearby buildings, seasonal conditions, the time of day, can even make reception impossible even when you are within range of the transmitter.
Proper reception may be impossible if there is something blocking
the signal. If reception is unsuccessful, try again.
This watch is designed to adjust its current time setting in
accordance with the calibration signal transmitted in Japan only. It operates like a standard (non-radio controlled) watch outside of the range of the receivable time calibration signal transmitters.
When the watch is unable to receive the time calibration signal for
some reason, timekeeping accuracy is within ±20 seconds per month.
Strong electrostatic charge can cause timekeeping error. Signal reception is cancelled if the alarm starts to sound while it is
being performed.
The watch’s calendar shows dates up to the year 2099.
Attempting a receive operation after that causes an error.
Receiving the Calibration Signal There are two methods you can use to receive the time calibration signal. Auto receive (Reception is performed automatically at midnight,
1:00, 2:00, 3:00, 4:00 and 5:00 each morning.)
Manual receive (You initiate reception using a button operation.) •When any auto receive is successful, further auto receive
operations for that day are not performed.
•Successful auto receive keeps timekeeping accurate.
To position the watch for optimum reception
Remove the watch from your wrist and place it somewhere so its right side (9 o’clock side, where the antenna is located) is facing a window.
9 o’clock
side
Or
•Do not move the watch while it is receiving the calibration signal.
Time Required for Reception
A calibration signal receive operation takes anywhere from about two to seven minutes.
To perform manual receive
In the Timekeeping Mode, hold down the BB
BB
Bbutton for about
two seconds.
The watch will beep, and signal reception will start.
To interrupt reception
Press any button.
When reception starts
The second hand moves to READY.
The hour and minute hands continue to keep time normally.
During reception
The second hand moves to WORK.
The hour and minute hands continue to keep time normally.
Do not move the watch until calibration signal reception is complete.
After reception is complete
If reception is successful, the second hand will move to GET. One or two minutes later, the hands will move to the correct time. If reception is not successful, the second hand will move to NG (No Good). One or two minutes later, the second hand will resume normal operation, without any adjustment of the hand setting.
Press the AA
AA
Abutton.
This will cause the minute hand to move counterclockwise about one or two minutes, and then stop around 12 o’clock.
Press the BB
BB
Bbutton.
Each press of the Bbutton moves the setting counterclockwise by one minute. Holding down the Bbutton for about two seconds moves the
hands counterclockwise at high speed. High-speed movement of the hands will continue until it completes a 12-hour cycle, or until you press any button to stop it.
4.
When the setting is the way you want, press the
AA AA
Abutton. This will cause the hour and minute hands to move to the current time, and the second hand to move to “ON”(alarm
on). Setting the alarm time causes the alarm to turn on automatically.
5.
Press the BB
BB
Bbutton twice
to return to the Timekeeping Mode. This causes the second hand to move to the seconds count of the current time and resume normal movement.
If you do not perform any button operation for about two or three
minutes, the watch will exit the setting mode and resume normal hand movement.
To turn the alarm on or off
In the Alarm Mode, press the
AA AA
Abutton to toggle the alarm on and off.
To stop the alarm beeper
Pressing any button while the beeper is sounding stops it.
OFF
ON
You can set an alarm time in 1-minute units. The watch beeps for 10 seconds when the alarm time is reached.
3.
Set the alarm time you want.
•If you want to set the alarm time by moving the hands
clockwise, go to step 3-a.
•If you want to set the alarm time by moving the hands
counterclockwise, go to step 3-b.
When setting the alarm time, take care to set AM and PM correctly. •The second hand will move between AM and PM any time
the hour hand moves past 12 o’clock while you are setting
the alarm time.
Press the BB
BB
Bbutton.
•
••
• • • • • • • • • • •
• •
• •
Each press of the Bbutton moves the setting clockwise by one minute.
•
Holding down the Bbutton for
about two seconds moves the hands clockwise at high speed. High-speed movement of the hands will continue until it completes a 12-hour cycle, or until you press any button to stop it.
•After the alarm time setting is the way you want, press the A
button to advance to step 4.
To set an alarm time
1.
In the Timekeeping Mode, press the BB
BB
Bbutton twice
to enter the Alarm Mode.
• • •
The second hand will move to either “ON”(alarm on) or “OFF”(alarm off).
2.
Hold down the AA
AA
Abutton
for five seconds to display the setting screen. The second hand will move to “AM”or “PM”.
Note that the hands do not move while the alarm setting screen is on the display.
OFF
ON
AM PM
Example: Midnight
Using the Alarm
■ ■
■
■ ■ ■ ■ ■ ■
To set the alarm time by moving the hands clockwise
3-a
To set the alarm time by moving the hands counterclockwise
3-b
■ ■

—5 —
5.
Press the AA
AA
Abutton to
advance to hour and minute hand home position adjustment.
•If current hour and minute
hand alignment is correct, they will both move to 12 o’clock.
6.
Check the position of the hour and minute hands.
•If the hour and minute hands
are not pointing at 12 o’clock, it means that their home position is off.
12 o’clock
Correct Alignment
12 o’clock
12 o’clock
3.
Check the position of the second hand. If the second hand is not pointing at 12 o’clock, it means that its home position is off.
If the second hand is pointing at 12 o’clock, advance to step 5.
4.
Press the BB
BB
Bbutton to
move the second hand clockwise, until it points at 12 o’clock.
• •
Each press of the Bbutton
advances the second hand by one second.
•Holding down the Bbutton
for about two seconds advances the second hand at high speed. High-speed movement of the second hand will continue until it completes a full revolution, or until you press any button to stop it.
Use the following procedure to adjust the home positions of the hands and the date when the time setting is wrong, even after the time calibration signal is received normally.
1.
In the Timekeeping Mode, press the BB
BB
Bbutton three
times to enter the Home Position Adjustment Mode.
2.
To adjust the second hand home position, hold down the AA
AA
Abutton until the
second hand performs a full rotation and stops (about five seconds).
•The analog hands do not
move during home position adjustment.
Correct Alignment
12 o’clock
12 o’clock
12 o’clock
Adjusting the Home Positions
If appears for the date, advance to step 13.
12.
Perform the following steps to adjust the date home position. Hold down the Bbutton for about two seconds to start automatic high-speed scrolling of the date. The is located between 31 and 1. When the date gets close to 31, press the Bbutton again to stop the scrolling. Press the Bbutton to advance the date until appears.
13.
Press the AA
AA
Abutton to exit
home position adjustment. This causes the date to change to the current date, and the hour and minute hands to move to the current time. Note that all button operations are disabled while the date is changing, and the hour and minute hands are moving.
If the hour and minute hands are pointing at 12 o’clock, advance to step 10.
9.
Use the following steps to move the hands counterclockwise.
•Press the Bbutton to align
the hour and minute hands with 12 o’clock.
•Each press of the Bbutton
moves the hand setting 10 seconds.
•Holding down the Bbutton
for about two seconds moves the hands at high speed. High-speed movement of the hands will continue until it completes a 12-hour cycle, or until you press any button to stop it.
•Move the hands at high speed until just before the setting you
want. Stop high-speed movement, and then press the B button to move in 10-second increments to move the hands to 12 o’clock.
10.
Press the AA
AA
Abutton to
advance to date home position adjustment.
•
• • •
The date indicator will show
if the date home position
is correct. Note that it can take up to 90 seconds before
appears.
11.
Check the date indicator.
•If the date indicator shows
something other than , it
means that the date home position is off.
12 o’clock
Correct Alignment
indicator
indicator
14.
Press the BB
BB
Bbutton to
return to the Timekeeping Mode.
•This causes the second hand
to move to the seconds count of the current time, where it starts normal movement.
The watch will return to the Timekeeping Mode automatically if you leave it in the Home Position Adjustment Mode without performing any button operation for two or three minutes.
After you complete the home position adjustment procedure, place the watch in a location that allows good time calibration signal reception, and then perform a manual receive operation. See “To perform manual receive”for more information.
If the hour and minute hands are pointing at 12 o’clock and you want to set the hands by moving them counterclockwise, advance to step 8.
7.
Adjust the hour and minute hand home position.
Use the following steps to move the hands clockwise.
• • • •
Press the Bbutton to align the hour and minute hands with 12 o’clock.
Each press of the Bbutton
moves the hand setting 10 seconds. Holding down the Bbutton for about two seconds moves the
hands at high speed. High-speed movement of the hands will continue until it completes a 12-hour cycle, or until you press any button to stop it. Move the hands at high speed until just before the setting you want. Stop high-speed movement, and then press the B button to move in 10-second increments to move the hands to 12 o’clock.
8.
To move the hands counterclockwise, press the AA
AA
Abutton.
•This will cause the minute
hand to move counterclockwise about one or two minutes, and then stop around 12 o’clock.
If the second hand home position is off
If the hour and minute hand home position is off does not appear for the dateIf
If the hour and minute hand home position is off

—6 —
To manually set the hour and minute
1. In the Timekeeping Mode,
hold down the AA
AA
Abutton
for about five seconds until the second hand stops at AM or PM. Note that the hands of the watch do not move in the manual setting mode. If you do not perform any button operation for about two or three minutes, the watch will exit the manual setting mode and normal hand movement will resume. Pressing the Abutton and the Bbutton at the same time in
the manual setting mode will cause the hands to move to the original (unadjusted) time setting. Then the watch will return to the Timekeeping Mode.
2. Use one of the operations described below set the hands.
To move the hands clockwise
Advance to step 2-a.
To move the hands counterclockwise
Advance to step 2-b.
When adjusting the hour and minute hands, make sure you set a.m. and p.m. times correctly. •Whenever the time setting passes 12 o’clock, the second
hand will switch between AM and PM.
AM
Example: Current time is
10:09 a.m. Press the BB
BB
Bbutton to move
the hands clockwise by one minute.
•Holding down the Bbutton for
about two seconds moves the hands clockwise at high speed. High-speed movement of the hands will continue until it completes a 12-hour cycle, or until you press any button to stop it.
•After setting the time you want, press the Abutton to advance to
step 3.
Press the AA
AA
Abutton.
•This will cause the minute hand
to move counterclockwise about one or two minutes, and then stop around 12 o’clock.
Press the BB
BB
Bbutton to move
the hands counterclockwise by one minute.
•Holding down the Bbutton for about two seconds moves the
hands counterclockwise at high speed. High-speed movement of the hands will continue until it completes a 12-hour cycle, or until you press any button to stop it.
If you become confused and lose your way during the following procedures, simply put the watch down and do not perform any button operation for two or three minutes. This will cause the watch to enter the Timekeeping Mode (indicated by normal one-second movement of the second hand) automatically. After that, you can try performing the manual setting procedure again from the beginning.
To manually reset the second hand to the top of the minute
1. In the Timekeeping Mode,
hold down the AA
AA
Abutton
for about five seconds until the second hand stops at AM or PM.
•If you do not perform any
button operation for about two or three minutes, the watch will exit the manual setting mode and normal hand movement will resume.
2. Press the AA
AA
Abutton twice.
•This will cause the second
hand to move to SEC.
•Note that the hands of the
watch do not move in the manual setting mode.
3. In accordance with a time
signal on the TV or radio, press the BB
BB
Bbutton.
•
• • •
This will increase the minute setting by one and restart the seconds count from 00.
•In Japan, you can obtain the
current time by dialing 117 on the telephone.
AM
Example: Current time is
10:08 a.m.
SEC
Adjusting the Time Manually
You can perform the following procedures to adjust the time and date when the watch is unable to receive a time calibration signal for some reason.
3. Press the BB
BB
Bbutton to
advance the date by one.
•If the watch automatically
skips the end of the month date (30 or 31) you are trying to set, first perform the steps below to change the month setting and then come back to adjust the date setting.
4. Press the AA
AA
Abutton.
•The second hand will move to
the current month setting.
Jan
Feb
Mar
Sep
Aug
Jul
Apr
Jun May
Nov Dec
Oct
Date
Current month
10’s digit of year setting
3. To return to the
Timekeeping Mode, press the AA
AA
Abutton six times.
•This will cause the hands to
move to the current time, and resume normal movement.
To adjust the date
1. In the Timekeeping Mode,
hold down the AA
AA
Abutton
for about five seconds until the second hand stops at AM or PM.
•Note that the hands of the
watch do not move in the manual setting mode.
•If you do not perform any
button operation for about two or three minutes, the watch will exit the manual setting mode and normal hand movement will resume.
2. Press the AA
AA
Abutton three
times.
•The second hand will move to
12 o’clock.
AM
Example: Current time is
10:09 a.m.
12 o’clock
5. Press the BB
BB
Bbutton to
advance the month by one.
6. Press the AA
AA
Abutton.
•The second hand will move to
the ten’s digit of the year setting.
10
20
30
90
80
70
40
60 50
00
■
■
■ ■
■
To set the alarm time by moving the hands counterclockwise
2-b
To set the alarm time by moving the hands clockwise
2-a

—7 —
7.
Press the BB
BB
Bbutton to
increase the ten’s digit setting by one.
•You can set the year within
the range of 2000 to 2099.
8
.
Press the AA
AA
Abutton.
•The second hand will move to
the one’s digit of the year setting.
1
2
3
9
8
7
4
65
0
9.
Press the BB
BB
Bbutton to
increase the one’s digit setting by one.
10.
Press the AA
AA
Abutton to
return to the Timekeeping Mode.
•This will cause the hands to
move to the current time, and resume normal movement.
•The watch automatically makes adjustments for leap years and
month lengths. The date will change automatically when the current time reaches midnight. The date change at the end of the month may take more time than normal.
Year (one
’
s di
g
it)
Power Saving puts the watch into a sleep state, which will cause the second hand to stop moving whenever the watch is left in the dark. •Note that hand movement may stop if the watch is blocked from light by your sleeve.
Power Saving
How the sleep state works
Sleep Level 1 The second hand stops whenever the watch is left in the dark for about one hour between the hours of 10:00 p.m. and 6:00 a.m. •The hour and minute hand, and the date continue to operate
normally.
•The alarm operates normally. Sleep Level 2 If the watch is left in the dark for an additional six or seven days, the hour and minute hands, and the date indicator also stop. •Auto time calibration is not performed. •The alarm does not sound. •Timekeeping continues internally even when the hands are
stopped.
To recover from the sleep state
Move the watch to a brightly lit location, press any button, or raise the watch to your eyes for viewing (see “To illuminate the face with the auto light switch”). The hands will move to the current time
setting and resume timekeeping from there.
■■

— 8 —
3. DRAWINGS: MODULE QW-3721
3-1. CIRCUIT DIAGRAM
GND VDD2
BAT
VCH VC1 VC2
C6 C4
XTB
Xtal
L1 - - - - - L8 L9 - - L17
LD1
S2
VDD1
BD
C7
XT
T1 T2 T3 KI4 KI2 KI3 KI1 KI5 KI6 KI7 KI8
S1
SCR SCIN
RP1RP2
Cp
VDSPVC3 VC4
Di1 VHF
C5
AC T4
KC4 KC2 KC3
R1
R2
VSC
SC
C8
R3
VPM
Rb
GNDB
✽5
✽1
✽4 ✽4 ✽4
✽3 ✽3
✽3 ✽3
✽7
✽8
✽9
An.B2
✽2 ✽2
O1 O2
✽3 ✽3
CG
O3 ✽1
An.B3
O4 O5 O6
An.B1
EMP ✽3PM_RES1
KC1
KC5
RPM Tr3
LS1 LS2 LCS
✽1✽1
✽10
✽11
LC1 - - LC3
✽1
✽1
GND1
VOUT0
COILB
LED
DRIVER
5ENABLE 4(N.C.) 3GND 2(N.C.) 1LEDOUT (N.C.)A
(N.C.)9
VDD8
CE276CE1
LED2
Dild1 LL2
LED1
Rld1 Rld2
Cld1
Cld2
Tr1
PZZ
Di2 R1
LL1
SK
KS✽6
Cxt
Ccp
Cbat
Rbat
Xtal2
ISB
ANT
Rcp
Xtal3
Cc
✽13
✽12 ✽13
FET-S
GND4
Asel Pon P3-2 Hold P14
FET-D
P1 P2
GND3 GND2
P3-1 P4 P5
GND5
P12
P13
GND1
TCO VCC
P9
P7
Crh1 Crh2 Crh3 Crl1 Crl2 Crl3
✽13 ✽13
✽13
✽15
SDA SCL SCUT
✽1✽1
✽1
✽1✽1✽1✽1
✽1
✽1
✽15
✽15
✽14✽14
✽14
LSI
TOTAL 74PINS
BONDING 49PINS
✽ 1. No bonding ✽ 2. GND-KI6: Short (Soldering) GND-KI7: Open (No Soldering) ✽3. Latch type key ✽ 4. Short (Soldering) (R trimming) ✽ 5. GNDB is used for the bias on the back of the tip.
Mount Rb close by the tip.
✽ 6. Inclination sensor ✽ 7. Normal Low ✽ 8. LD2 (Normal High) is used in this module. ✽ 9. LD3 (Normal Low) is used in this module.
✽ 10. LD4 (Normal Low) is used in this module. ✽ 11. XT_DVR is used in this module. ✽ 12. Cxt is not mounted in the specification for dual transmitters. ✽ 13. Cc, Crl1, Crl2, Crl3, Rxt3 and Xtal3 are not mounted in the specification for single transmitter. ✽14. Soldering short pad. (Short after tuning antenna.) ✽15. Any one of VCC, P3-1 and P3-2 should be wired to Rbat and Cbat since their terminals are wired inside ISB.

—9 —
3-2. CHECKING TERMINALS AND COMPONENTS
Short pad for R trimming
SENSOR/TILT
(71055275)
Short pad for switching modules
OSCILLATOR/CRYSTAL
(10008260)
TAPE/ADHESIVE 2306
(10006652)
SHEET/INSULATION 3721
(10172630)
9. PCB ASS'Y
(76408256)
O3
GND
VHF
KI6
VOUT
GND
LEDOUT LED2
LED2
VOUT
VDD2
LED1
O1
KI2
XT
XTB
VSC
KI5
VOUT
Ccp
VCH
LL1
KI4
VDD2
VDD2
FET-D
P2
P9
GND
VOUT
GND
GND
GND
GND
GND
GND
GND
KI7
R1
R2
R3
GND
CE2
CE1
Coil
LEDOUT
LED1
GND
XT
VDD2
Vcc
O5
O6
Coil
O2
O1
KI7
GND
GNDVC3
GNDB
KI4
P2'
Tr1
VDD2
AC
O1
P1'
VPM
VDD2
LL1 VDD2
GND
VSC
VSC
LD1
Coil
GND
VOUT
GND
VDD2
CE2
GND
GND
GND
LEDOUT
LD1
CE1
P2'
VDD2
VSC
P1'
O6
VCH
Tr1
GND
VC3
VC4
KI2
KI2
KI1
KI5
KI3
VOUT
O5
GND KI5
LL1
LL1
GND
SCR
SCIN
RPM
KC1
FET-S'
P1'
P2'P2'P2'
FET-S'FET-S'
P2
P7
P4 P5P7
Ccp
GND
FET-S'
P5P7
FET-S P1
GNDGND
Vcc
Tr1 BD
1.05MAX.
GND

— 10 —
4. EXPLODED VIEW: MODULE QW-3721
6 (10172615)
17 (10169534)
Casing parts: DIAL
Casing parts: SPACER
Casing parts: DIAL SUPPORTER
1 (76408219)
5 (10195754)
12 (10123230)
12 (10123230)
10 (10137168)
10 (10137168)
11 (10137169)
11 (10137169)
3 (10172616)
21 (72270294)
4 (10172619)
2 (10135068)
Battery storage (CTL1025)
16 (72301000)
14 (10135066)
18 (10169533)
20 (10169526)
9 (76408256)
PCB Ass'y
7 (10140782)
22 (10165772)
Casing parts: SOLAR CELL

5. PARTS LIST: MODULE QW-3721
Note: 1. Prices and specifications are subject to change without prior notice.
2. Spare parts are classified as follows according to their importance in after-sales service.
A Rank ---------------------------------------- Very Important
B Rank ---------------------------------------- Important
C Rank ---------------------------------------
-
Less important
3. Batteries in Bulk pack on the tray will be supplied from our Overseas Spare Parts Section under charge basis.
Batteries in Blister pack will be supplied from our Sales Department.
4. As for order/supply of spare parts, refer to the separate publication "GUIDE BOOK for spare parts supply".
Item Code No. Parts Name S
p
ecification A
pp
licable Q R
76408221 MODULE/WITH MOVEMENT QW-3721YC-02TK OCW-100TDJ-1A 1 A
OCW-110TDJ-1A
1 76408219 ANALOG BLOCK QW-3721MV-83TK QW-3721YC-02TK 1 A
2 10135068 BATTERY/STORAGE CTL1025 QW-3721YC-02TK 1 B
3 10172616 CONTACT/BATTERY (+) 3721 RJQ519936-001V02 QW-3721YC-02TK 1 C
4 10172619 CUSHION 3707-1 RJQ521249-002V01 QW-3721YC-02TK 1 C
5 10195754 CUSHION 3707-2 RJQ524197-001V03 QW-3721YC-02TK 1 C
6 10172615 HOLDER 3721 RJQ519902-001V01 QW-3721YC-02TK 1 C
7 10140782 LABEL 2815 RJQ517198-001V02 QW-3721YC-02TK 1 C
8 10008260 OSCILLATOR/CRYSTAL CFS-145JK07 QW-3721YC-02TK 1 B
9 76408256 PCB ASS'Y RJQ521705*001V01TK QW-3721YC-02TK 1 A
10 10137168 PLATE/TERMINAL 2787-1 RJQ515398-001V02 QW-3721YC-02TK 2 C
11 10137169 PLATE/TERMINAL 2787-2 RJQ515399-001V02 QW-3721YC-02TK 2 C
12 10123230 SCREW/FLAT2730 RJQ513792-001V01 QW-3721YC-02TK 4 B
13 71055275 SENSOR/TILT TS-2418-P QW-3721YC-02TK 1 B
14 10135066 SHEET/INSULATION 3315-3 RJQ515074-001V01 QW-3721YC-02TK 1 C
15 10172630 SHEET/INSULATION 3721 RJQ520957-001V01 QW-3721YC-02TK 1 C
16 72301000 SPRING/COIL 1604 Q458175A-1 QW-3721YC-02TK 1 B
17 10169534 SPRING/COIL 3707 RJQ521069-001V01 QW-3721YC-02TK 2 B
18 10169533 SPRING/LEAF 3707 RJQ520528-001V02 QW-3721YC-02TK 1 C
19 10006652 TAPE/ADHESIVE 2306 Q465964-1 QW-3721YC-02TK 1 C
20 10169526 TAPE/ADHESIVE 3707 RJQ521248-001V01 QW-3721YC-02TK 1 C
21 72270294 WASHER/745 Q436294A-1 QW-3721YC-02TK 1 C
22 10165772 WHEEL/HOUR 3721 RJQ519790-001V01 QW-3721YC-02TK 1 C
For the prices and minimum order/suppl
y
quantities of the above parts, refer to the Parts Price List P.P.L.-623.
Notes: Q - Used quantity
R - Rank — 11 —

—12 —
6. PRECAUTIONS FOR REPAIR: MODULE QW-3721
6-1. AC (ALL CLEAR) AND REMOVING OF MODULE
1. Perform AC (ALL CLEAR) when inserting a new battery, or else the memories and/ or counters may give
erratic displays.
Touch the AC contact and the main plate with the metallic tweezers.
The contact should be made for about two seconds.
2. On removing of the module from the case, please insert the precision screw driver between the module
and the case pointed by arrows.
Note:After performing AC(ALL CLEAR), the mode is switched to the second hand movement accuracy
check mode at the home position adjustment mode.
6-2. ACCURACY CHECKING
1. Module confirmation mode
1) While pressing Abutton, press Bbutton twice at the normal timekeeping mode.
2) Confirm that the second hand points at 1 o’clock.
3) Press Abutton at the module confirmation mode to enter the normal timekeeping mode.
2. Accuracy checking mode
1) Press Bbutton at the module confirmation mode to enter the accuracy checking mode.
2) Second hand shows performing to test the rate of clock.
3) Press Abutton at the Accuracy checking mode to go back to the normal timekeeping mode.
Metallic tweezers
B
A+B×2
A
Module confirmation mode
Normal timekeeping mode
Accuracy checking mode
B
A

—13 —
6-3. SOLAR CELL-PCB ASS'Y CONTACT CHECKING
1) Press Bbutton at the accuracy checking mode, referring to page 10 to enter the solar cell-PCB
ass’y contact mode.
2) Check a Solar cell and PCB ass’y contact by the second hand.
3) Press Abutton at the solar cell-PCB ass’y contact mode, to go back to the normal timekeeping mode.
6-4. TIME CALIBRATION SIGNAL TEST MODE
1) While pressing Abutton, press Bbutton twice to enter the time calibration mode at Receive Result
Mode.
2) Press Abutton or Bbutton to start signal reception. The second hand represents the result of the
signal reception.
* While the signal reception, second hand drives normally.
3) While the signal reception, pressing Abutton, Bbutton, or Abutton and Bbutton at the same
time switches to the normal setting.
6-5. SECOND HAND MOVEMENT ACCURACY CHECK MODE
1) While pressing Abutton, press Bbutton twice at the hand setting mode to enter the second hand
movement accuracy check mode at Home Position Adjustment Mode.
2) Press Aor Bbutton to start testing.
3) While testing, pressing Aor Bbutton stops testing.
4) Pressing Abutton and Bbutton at the same time, or pressing Abutton at the date function
accuracy check mode switches to the normal timekeeping mode.
Aor B
A+B×2Time calibration signal test mode
The result of the signal reception
Start signal reception Aor B
A+B
B
A
Normal timekeeping mode
B
A
AA+B×2
A+B
Hand movement accuracy
check mode
Hand setting
Date function accuracy
check mode
Second hand continuance
movement accuracy check
Normal timekeeping mode
Stop testing
A
B
Aor B
Contrasting Second hand position
Bright position at 40 sec
Dark position at 55 sec
Signal recieving department Start signal reception The result of the signal reception
Success failure
JJY40 B1 o’clock 11 o’clock
JJY60 A2 o’clock 10 o’clock

—14 —
7. TROUBLESHOOTING: MODULE QW-3721
This is a flow chart about signal reception.
Yes
No
Yes
No
Yes
No
START
Check whether the Home City
code is selected correctly.
To perform MANUAL time
calibration signal reception
OK
There is a possibility of location bad.
To perform AUTO time
calibration signal reception
Replace the PCB ass'y
Signal
reception OK?
Signal
reception OK?
Signal
reception OK?
OK
OK

Ver. 1 : Jun. 2010
Correction of page 10
CASIO COMPUTER CO.,LTD.
Overseas Service Division
6-2, Hon-machi 1-Chome
Shibuya-ku, Tokyo 151-8543, Japan