Komatsu PC400LC-5 Operation & Maintenance Manual page 96

NOTICE
Canceling automatic warming-up operation
If it becomes necessary in an emergency to lower the engine speed
to low idling, cancel the automatic warming-up operation as fol-
lows.
1. Turn fuel control dial @to the full speed (MAX) position and hold
it for 3 seconds.
AE097590
2. When fuel control dial @ is returned to the low idling (MIN)
position, the engine speed will drop.
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