Onan

OC

UnclassifiedSpeed

What This Code Means

Engine malfunction shutdown immediately after start; Overspeed light on; Engine overspeed during operation; Engine stops running after about 12 seconds; LOP lamp comes on; Engine stops running after about 1 minute; OC (overcrank) lamp comes on; Engine shuts down after running short time; LOP lamp comes on and engine stops running after about 12 seconds; OC (overcrank) lamp comes on and engine stops after running about 1 minute; Engine malfunction shutdown; Engine does not overspeed during operation; Engine overspeeds during operation; Engine malfunction shutdown immediately after start with overspeed light on; Engine overspeed during operation with overspeed light on; Engine malfunction shutdown with overspeed light on but engine did not overspeed during operation

Possible Causes

  • •Fault in Shutdown module
  • •Fault in Fno+ Overspeed module
  • •Stuck or restricted throttle linkage
  • •Stuck or restricted governor linkage
  • •Remote governor control set at High RPM position
  • •Engine not pumping oil properly
  • •Defective oil pressure sensor
  • •Defective Start-Disconnect module J3
  • •Start-Disconnect does not operate after engine starts
  • •Defective Engine Monitor module J5
  • •Throttle & governor linkage restricted movement
  • •Fault in Overspeed module
  • •Start-Disconnect module J3 malfunction
  • •Faulty Engine Monitor module J5
  • •Throttle and governor linkage binding or restricted
  • •Faulty Start-Disconnect module J3
  • •Throttle and governor linkage binding

Suggested Actions

  1. 1Check throttle and governor linkage for free movement
  2. 2Ensure remote governor control is not set at 'High RPM' position
  3. 3Remove wire from terminal TB11-30 (PI-6 to SI) and reset
  4. 4Disconnect module J3 to check if engine runs OK
  5. 5Check or replace Start-Disconnect module J3
  6. 6Check for B+ voltage at K13 terminal 3
  7. 7Check or replace Engine Monitor module J5
  8. 8Check throttle & governor linkage for free movement
  9. 9Ensure remote governor control is not set at High RPM position
  10. 10Check or replace Shutdown module
  11. 11Check or replace Overspeed module
  12. 12Remove wire from terminal TB11-30 (P1-6 to S1) and reset
  13. 13Reconnect wire
  14. 14Check for B+ at K13 terminal 3 to verify Start-Disconnect operation
  15. 15Inspect or replace Shutdown module
  16. 16Inspect or replace Overspeed module
  17. 17Remove wire from terminal TB11-30 (P1-6 to S1), reset, and test if engine runs OK
  18. 18Reconnect wire after testing
  19. 19Repair engine oil pumping system
  20. 20Replace defective oil pressure sensor

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