How to Set the Time on the G-SHOCK GA-2100

Understanding the Button Layout

The GA-2100 features four buttons：

• A (Adjust): Top-left
• B (Light): Top-right
• C (Mode): Bottom-left
• D (Start/Stop): Bottom-right​

Step-by-Step Time Setting Instructions

1. Enter Timekeeping Mode:
   • Press the C (Mode) button repeatedly until the time is displayed on the digital screen.​
2. Access Time Setting Mode:
   • Hold down the A (Adjust) button for about 2 seconds until the city code starts flashing on the digital display.​
3. Select Your Home City:
   • Use the D (Start/Stop) button to scroll forward through city codes and the B (Light) button to scroll backward.
   • Choose the city code that represents your current time zone.​
4. Adjust Daylight Saving Time (DST):
   • Press the C (Mode) button to move to the DST setting.
   • Use the D (Start/Stop) button to toggle between ON and OFF.​
5. Set the Time Format:
   • Press the C (Mode) button to navigate to the 12/24-hour format setting.
   • Use the D (Start/Stop) button to select your preferred format.​
6. Set the Seconds, Hours, and Minutes:
   • Press the C (Mode) button to move to the seconds setting.
   • Use the D (Start/Stop) button to reset the seconds to 00.
   • Press the C (Mode) button to move to the hour setting.
   • Use the D (Start/Stop) button to increase the hour and the B (Light) button to decrease it.
   • Repeat the process for minutes.​
7. Set the Year, Month, and Day:
   • Continue pressing the C (Mode) button to navigate through the year, month, and day settings.
   • Use the D (Start/Stop) and B (Light) buttons to adjust each value accordingly.​
8. Finalize the Settings:
   • After all settings are adjusted, press the A (Adjust) button to exit the setting mode.

Synchronizing Analog Hands with Digital Time

If the analog hands do not match the digital time, follow these steps:​

1. Enter Hand Setting Mode:
   • Hold down the A (Adjust) button for about 5 seconds until “H-SET” appears on the digital display.​
2. Adjust the Hands:
   • Use the D (Start/Stop) button to move the hands forward and the B (Light) button to move them backward.
   • Align the hands to match the digital time precisely.​
3. Exit Hand Setting Mode:
   • Press the A (Adjust) button to exit. The hands will now move to the correct time.