Onan

LOW OIL PRESSURE LAMP

UnclassifiedCooling

What This Code Means

K13 relay does not energize; Engine does not crank; High Engine Temperature fault lamp lights; Low Oil Pressure fault lamp lights; Overcrank fault lamp lights; Overspeed fault lamp lights; Engine stops when running

Possible Causes

  • •Faulty K13 start solenoid relay
  • •Faulty Engine Monitor module J5
  • •Faulty starter
  • •Faulty Cycle Cranker module J4
  • •Poor terminal connections
  • •Bare wires and shorts to ground
  • •Faulty engine temperature sensor (HET)
  • •Low oil level in engine crankcase
  • •Faulty Engine Monitor board J5
  • •Faulty LOP switch
  • •Grounded wire
  • •Oil system malfunction
  • •K13 pin 1 not grounded
  • •Faulty Start-Disconnect module J3
  • •Defective OS module J4
  • •Bare wires grounding terminal TB11-40

Suggested Actions

  1. 1Replace starter
  2. 2Replace K13 start solenoid relay
  3. 3Replace Engine Monitor module J5
  4. 4Replace Cycle Cranker module J4 and check connections
  5. 5Inspect for bare wires and shorts to ground
  6. 6Replace engine temperature sensor (HET)
  7. 7Inspect oil level in engine crankcase
  8. 8Check Start-Disconnect module J3 and Reset
  9. 9Check for defective OS module J4 or bare wires grounding terminal TB11-40

Related Onan Fault Codes

O.C.O.S.LOW OIL PRESSUREOVERCRANKLOW ENGINE TEMPERATUREOVERCRANK LAMPLOPOVERSPEEDLETOVERSPEED LAMPHIGH ENGINE TEMPERATURE LAMPHIGH ENGINE TEMPERATURE
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