Onan

12

UnclassifiedElectrical

What This Code Means

Engine will not shut off (Run Light is Off); Over Voltage (controller can not regulate to rated voltage); Under Voltage (controller can not regulate to rated voltage); Loss of Raw Water Flow; Overvoltage; Undervoltage; Excessive Smoke Under Load; No AC Output (Genset)

Possible Causes

  • •Binding in the governor linkage
  • •Blocked heat exchanger
  • •Control plugs not fully seated
  • •Faulty field windings
  • •Faulty genset control PCB
  • •Faulty raw water impeller
  • •Fuel supply issues
  • •Grounded field windings
  • •Grounded or shorted field windings
  • •Grounded or shorted main windings
  • •Grounded or shorted stator windings
  • •Improper field resistance (open to ground)
  • •Incorrect loads
  • •Incorrect output voltage
  • •Loose sense lead connections
  • •Opens and/or shorts in stator and rotor
  • •Overload Condition
  • •Poor brush condition and contact
  • •Raw water impeller malfunction
  • •Sense leads not fully seated in connector to control
  • •Shorted field windings
  • •Worn or damaged brushes and slip rings

Suggested Actions

  1. 1Check blocked heat exchanger
  2. 2Check brush condition and contact
  3. 3Check circuit breaker
  4. 4Check control
  5. 5Check field windings
  6. 6Check for binding in the governor linkage
  7. 7Check for blocked heat exchanger
  8. 8Check for grounded or shorted main windings
  9. 9Check for proper field resistance reading, open to ground
  10. 10Check fuel supply
  11. 11Check if control plugs are fully seated
  12. 12Check if sense leads are fully seated in connector to control
  13. 13Check loads
  14. 14Check output voltage
  15. 15Check raw water impeller
  16. 16Check sense lead connections
  17. 17Check sense leads fully seated in connector to control
  18. 18Check stator and rotor for opens and/or shorts
  19. 19Replace the genset control PCB
  20. 20Service the brushes and slip rings as necessary
  21. 21Verify control plugs are fully seated
  22. 22Verify sense leads are fully seated in connector to control

Related Onan Fault Codes

131400-0AZ1500-0AM2700-0AH2900-0AG3200-0AB35
Browse all Onan fault codes

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