Komatsu PC138USLC Operation & Maintenance Manual page 112

OPERATION
Adjusting Screen
Use this screen adjustment menu to adjust the brightness,
contrast, and back light of the screen.
1. On the standard screen, press switch F6.
2. Select screen adjustment on the user menu, then press switch
F6. The screen switches to the selection menu screen for
screen adjustment.
On machines equipped with cameras, it is possible to adjust
the brightness, contrast, and back light of the cameras
screen on this menu.
DETAILED CONTROLS AND GAUGES
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