Komatsu PC138USLC Operation & Maintenance Manual page 127

OPERATION
DETAILED CONTROLS AND GAUGES
Revolving Warning Lamp Switch
(If equipped)
Use this switch (10) to light up the yellow rotating lamp on top of the
cab.
(a) ON: Lamps light up
(b) OFF: Lamps go off
Roof Glass Wiper Switch
(If equipped)
Use this switch (11) to operate the wiper and spray out washer fluid
for the glass in the cab roof.
Wiper position (a): Roof glass wiper is actuated
Washer position (b) is as:
When the switch is kept pressed, washer fluid is sprayed out onto
the roof glass and the wiper is actuated.
When the switch is released, it returns to position (a). The washer
fluid stops, and only the roof glass wiper continues to be actuated.
Stop position (c): Roof glass wiper stops
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