K-3.9 TURNING THE ENGINE COOLANT HEATER OFF ALL MODES
Press heater "On"
pushbutton (3, Figure K-1). The engine coolant heater will shutdown
after its normal cool down cycle is complete. The time of day will remain displayed when the
crane's ignition switch is on.
The seven day timer will display fault code numbers if the engine coolant
heater shuts down due to an operating fault. A fault code will appear in
place of the time and day display (7, Figure K-1). The fault codes can be
used by maintenance to troubleshoot the system
If the engine coolant heater fails, check the following before contacting
maintenance to troubleshoot the heater.
Check electrical connections and the in-line fuses (in the battery box
and engine coolant heater box). Ensure that the crane's batteries are
Check the fuel source.
Check for coolant flow from the crane's engine coolant system.
Contact maintenance to troubleshoot and repair the engine coolant heater. Refer to TM 5-
K-4 Change 1