Cummins 249 Ambient Air Temperature Sensor 1 Circuit - Voltage Above Normal or Shorted to High Source
What this code means
Cummins fault code 249 refers to: Ambient Air Temperature Sensor 1 Circuit - Voltage Above Normal or Shorted to High Source. It is logged by the engine control module (ECM) on Cummins-powered vehicles and read over the J1939 diagnostic network.
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Cummins fault code 249 indicates ambient air temperature sensor 1 circuit - voltage above normal or shorted to high source.
Cummins 249 is generally treated as a moderate-severity fault. Have the engine and its wiring inspected, and confirm the reading with a J1939 diagnostic scan before clearing the code.
