Komatsu PC220LC -8 Operation & Maintenance Manual page 120

OPERATION
3. On the clock adjustment selection screen, it is possible to carry out the following operations with switches F3
to F6.
Time
Adjust the hour setting.
1) If "Time" (a) is not highlighted in yellow, press switch F6 to
highlight "Time" (a) in yellow. When this is done, hour
display (b) changes to orange.
Adjust hour display (b) with the switches as follows. If it is
not necessary to change the hour setting, press switch F6.
F3: Time advances 1 hour.
F4: Time goes back 1 hour.
F5: Cancels change and returns to user menu.
F6: Accepts change and goes to setting for minutes.
DETAILED CONTROLS AND GAUGES
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