151

UnclassifiedCooling

What This Code Means

High AC Current; Shutdown; Low Oil Pressure; High Coolant Temperature; Pre - High Coolant Temp - Warning; CIRCUIT BREAKER (AC MAIN) TRIPS; EXCESSIVE EXHAUST SMOKE (BLACK)

Possible Causes

  • Overload
  • Faulty CTs or CT connections
  • Faulty harness or base board
  • Incorrect rating setup
  • Low oil level
  • Clogged oil pipe or filters
  • Faulty oil pressure sensor
  • Faulty engine or sensor circuitry
  • Low coolant level
  • Coolant leak
  • Obstructions in cooling air-flow
  • Increase in load
  • High ambient temp
  • Loose wire connections
  • Excessive or improper loads
  • Fuel supply issues
  • Intake restriction
  • Excessive loads

Suggested Actions

  1. 1Perform fault simulation with InPower
  2. 2Reset or adjust threshold
  3. 3Check CTs and CT connections
  4. 4Check harness and base board
  5. 5Reset Control & restart
  6. 6Perform fault simulation with InPower for oil pressure sensor
  7. 7Top up oil level
  8. 8Check oil pipe and filters for clogs
  9. 9Check oil pressure sensor with simulator
  10. 10Perform fault simulation with InPower for coolant sensor
  11. 11Check engine or sensor circuitry
  12. 12Check coolant temperature sensor reading with thermocouple
  13. 13Check coolant temperature sensor resistance
  14. 14Check coolant level
  15. 15Check for coolant leaks
  16. 16Check for obstructions in cooling air-flow
  17. 17Refer to PCC1302 troubleshooting guidelines
  18. 18Review fault code 151 correction list for other possible causes
  19. 19Evaluate fault codes
  20. 20Check loads

Related Onan Fault Codes

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