RV Appliance Code Atlas

Onan 58 fault code — Generator

Applies to: HGJAA Spec J-K, HGJAB Spec J-L, QG 5500/7000 EFI, HGJAA Spec A-E, HGJAB Spec A-E, HGJAC Spec A-D

What 58 means

The Cummins Onan operator manual lists Code 58 as Exhaust Gas Temperature Shutdown.

Owner-safe checks

  • Turn the generator off and let it cool.
  • Do not restart if exhaust, airflow, or heat conditions appear abnormal.

Service-only work

  • Internal generator electrical, fuel, engine, sensor, controller, and output-voltage diagnosis belongs to Cummins service or a qualified generator technician.

Safety boundary

Generators can produce carbon monoxide, moving-part hazards, fuel hazards, and lethal voltage. Shut the generator down and do not open energized compartments unless qualified.

Official sources

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