Onan

45

UnclassifiedCooling

What This Code Means

Field Overload; Speed Sense Fault; Controller does not sense quadrature frequency and voltage; External Coolant Loss; Coolant in oil; Engine Unstable; Genset Hunts; Genset Surges; Speed sense loss; High exhaust temperature; Loss of Speed Sense; Excessive Fuel Pump Prime Time; Coolant Loss; Speed Sense Loss; High Exhaust Temp; Emergency Shutdown; Excessive Smoke Under Load

Possible Causes

  • •AC output issues
  • •Broken or loose switch leads
  • •Control plugs not fully seated
  • •Coolant in oil
  • •Cracked or leaking hoses
  • •Excessive load
  • •Faulty generator brush block
  • •Faulty generator rotor
  • •Faulty generator stator assembly
  • •Faulty genset control PCB
  • •Faulty local or remote Start/Stop switches
  • •Faulty pin connections
  • •Faulty slip rings
  • •Fuel lines leaking
  • •Fuel supply issues
  • •Grounded or shorted quad windings
  • •Leaks or defects in radiator
  • •Loose clamps
  • •Loose hose clamps
  • •Loose wiring connections
  • •Low coolant level
  • •Open circuit across pins P1-1 and P1-10 (field windings)
  • •Open circuit across pins P1-3 and P1-9 (quadrature windings)
  • •Open, short, or ground in rotor/stator windings
  • •Opens, shorts, or grounds in field resistance
  • •Opens, shorts, or grounds in quad resistance
  • •Quad leads not fully seated in connector to control
  • •Shorted wiring on set & remote

Suggested Actions

  1. 1Check F2 Fuse
  2. 2Check K2 relay and connections
  3. 3Check all pin connections and pin condition, and replace as necessary
  4. 4Check control
  5. 5Check control plugs fully seated
  6. 6Check field windings
  7. 7Check for leaking fuel lines
  8. 8Check for loose wiring connections
  9. 9Check fuel supply
  10. 10Check loads for proper operation
  11. 11Check quad leads fully seated in connector to control
  12. 12Check rotor/stator windings for opens/shorts/grounds
  13. 13Check starter circuits
  14. 14Disconnect genset control connector P1 and check for electrical continuity across pins P1-1 and P1-10 (field windings)
  15. 15Disconnect genset control connector P1 and check for electrical continuity across pins P1-3 and P1-9 (quadrature windings)
  16. 16Operate and check for leaks
  17. 17Pressure test coolant system
  18. 18Replace the generator stator assembly if the quadrature windings circuit is open
  19. 19Replace the genset control PCB
  20. 20Service or replace the generator rotor if the field windings circuit is still open
  21. 21Service the generator brush block and slip rings and repeat the test if the field windings circuit is open
  22. 22Verify proper field resistance reading, open to ground
  23. 23Visually check coolant level
  24. 24Visually check for coolant in oil
  25. 25Visually check for cracked or leaking hoses
  26. 26Visually check for leaks or defects in radiator
  27. 27Visually check for loose clamps

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