Komatsu PC118MR-8 Operation And Maintenance Manual page 105

FUNCTIONING
Indicators and counter
(10) Engine coolant temperature indicator
This gauge (10) indicates the engine coolant temperature.
During normal operation, the needle should remain within the
green area. If the needle exceeds the red zone (A), the
overheat protection system is activated.
q (A) - (B): Red zone
q (A) - (C): Green zone
q (C) - (D): White zone
The overheat protection system functions as follows.
q Red zone position (A): The engine coolant temperature
warning light (E) indicates a fault (red)
q Red zone position (B): Engine speed is reduced to idle, the
coolant temperature warning light (E) indicates a fault (red)
and the alarm buzzer sounds simultaneously.
The overheat protection system continues operating until the
needle returns to the green zone.
If the gauge needle is in position (C) upon engine start, the
coolant temperature warning light (E) indicates that the
temperature is too low. If this occurs, carry out the warming-up
procedure.
For more details, see "Warming the engine (3-137)".
q Warning light low temperature state (G): Background of
indicator (K) is white
q Warning light correct temperature state (H): Background of
indicator (K) is blue
q Warning light fault state (J): Background of indicator (K) is
red
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INSTRUMENTS AND CONTROLS
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