Last update: August 8th, 2018

Don't let the battery die inside the watch

It will eventually leak and damage the watch.
(Type 50 only). There is also an internal coin cell to keep time when the main battery is dead or during its replacement. As soon as you notice that the internal coin cell is not performing its duty anymore, it should be replaced to avoid internal leakage. Note that this cell is optional and can be removed by opening the back screw cover with the appropriate watch tool and pulling off the press-fitted circuit board.

If you wish to replace the wristband

Any 24 mm wristband (measured inside the case horns) you find from online vendor will do.
Use a small flat-blade screwdriver to undo the pin. Type 40 has a screw-type pin (unfasten each side) while the Type 50 has a spring-type pin (use the blade to press the blade between the wristband and the case horn).

Operating manuals

• Type 40
• Type 50

Troubleshooting tips

If the watch does not work after inserting a fresh battery:

• Don't use Duracell brand batteries, the positive tip is shorter than other brands and does not make proper contact internally. Energizer brand is recommended.
• Open and disassemble the door (with hex key). Clean all exposed metal contacts.
Inspect interior of the watch to ensure previous battery did not leak and damage the circuit board.
(Type 40 only) Make sure the golden spring-loaded contact in the door hinge is clean and free to move (use a wooden toothpick for inspection to avoid damage).
Perform simple electrical contact test to see if the door is the culprit (Type 40Type 50Type 50X).
If it's not already the case, place a fine steel wool ball in the door spring. Use pure steel wool that does not have chemicals in it.
If the watch has been turned on momentarily (e.g.: closing the door and re-opening it), it is possible the watch will not turn on again unless internal capacitance is fully discharged. In doubt, let the door open for 5 minutes to allow for a complete discharge before attempting to turn on the watch again.

If the watch does not program

Determine if the watch is in programming mode. For Type 40, the programming mode disables all other functions and the display won't respond until time is set (or 2-minute time out). For Type 50, the display responds proportionally to the amount of light shined on the back of the watch. Refer to operations manual (links above) if unsure.
Set brightness of your programming device to maximum.
Place the watch 20 cm away from the programming device's screen (this limits the amount of lights entering the watch and prevent saturation of light sensor).
If using an android phone, use the app and not the website (app sets brightness to maximum automatically and have better control over timing).
Move to a different programming device if all the above does not help.