HET
What This Code Means
Engine malfunction shutdown; Common fault lamp is illuminated and none of the diagnostic diodes (overcrank, low oil pressure, high engine temperature) are illuminated; Engine does not start within 75 seconds during cycle cranking; Engine monitor lights fault lamp and opens the cranking circuit; High engine temperature warning/shutdown; Low oil pressure warning/shutdown; Low engine temperature fault lamp illuminated (no associated engine shutdown); Low oil pressure; Engine shutdown; Engine fails to start; Overspeed; High engine temperature; Low engine temperature; Fault light illuminated; Fault lamp illuminates; Overspeed switch on the generator end bell closes
Possible Causes
- •Overspeed condition (approximately 2100 r/min)
- •Overcrank (failure to start)
- •Engine temperature reaches 215°F (102°C)
- •Oil pressure reaches 97 kPa
- •Low engine temperature
- •Engine malfunction
- •Failure to start within a 75-second cranking period
- •Failure to build up oil pressure within approximately 12 seconds
- •Fault in engine operation
- •High engine temperature (HET) pre-alarm switch operates while Pre-Alarm Shutdown Switch S11 is in Shutdown position
- •Low oil pressure (LOP) pre-alarm switch operates while Pre-Alarm Shutdown Switch S11 is in Shutdown position
- •Generator speed reaches between 2000 to 2200 r/min
Suggested Actions
- 1Manually reset the engine monitor using the Reset Switch after an engine shutdown
- 2Have control panel interior components adjusted, tested, or replaced by a qualified service representative
- 3Use the manual reset switch for the engine monitor after an engine shutdown
- 4Refer to the one-light troubleshooting guide for fault location
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