Komatsu PC400LC-5 Operation & Maintenance Manual page 87

After approx. 3 set, the following gauges will remain on and the
other monitors will go out.
l
l
(2)
Engine water temperature gauge @
Fuel gauge @I
Press lamp switch @ to turn on the head lamps.
If the lamps do not light up, there is probably a broken bulb or
disconnection in the wiring, so contact your Komatsu distributor
for repairs.
AD097060
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