43

UnclassifiedCooling

What This Code Means

Loss of Speed Sense; Excessive Fuel Pump Prime Time; Coolant Loss; Excessive Smoke Under Load

Possible Causes

  • AC output issues
  • Coolant in oil
  • Cracked or leaking hoses
  • Faulty genset control PCB
  • Faulty local or remote Start/Stop switches
  • Field resistance open, short, or ground
  • Fuel supply issue
  • Fuel supply issues
  • Loose hose clamps
  • Low coolant level
  • Opens, shorts, or grounds in field resistance
  • Opens, shorts, or grounds in quad resistance
  • Overload Condition
  • Quad resistance open, short, or ground
  • Shorted wiring on set & remote

Suggested Actions

  1. 1Check AC output
  2. 2Check coolant level
  3. 3Check field resistance for opens, shorts, and grounds
  4. 4Check field resistance for opens/shorts/grounds
  5. 5Check for coolant in oil
  6. 6Check for cracked or leaking hoses
  7. 7Check for loose hose clamps
  8. 8Check for shorted wiring on set and remote
  9. 9Check fuel supply
  10. 10Check local and remote Start/Stop switches
  11. 11Check quad resistance for opens, shorts, and grounds
  12. 12Check quad resistance for opens/shorts/grounds
  13. 13Check shorted wiring on set & remote
  14. 14Check start/stop switches (local & remote)
  15. 15Evaluate fault codes
  16. 16Pressure test cooling system (cold)
  17. 17Pressure test cooling system (hot)
  18. 18Replace the genset control PCB

Related Onan Fault Codes

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