Reason:
Auxiliary Temperature Sensor Input 1 – Special Instructions. The original equipment manufacturer (OEM) auxiliary temperature sensor input has exeeded an OEM calibrated limit.

Effect:
Engine power derate.

Circuit Description:
The original equipment manufacturer (OEM) has the option of wiring a temperature sensor input to the Cummins® engine control module (ECM). This input is intended for a variable resistance temperature sensor.

Component Location:
The OEM temperature sensor input and location will vary. Refer to the OEM service manual for sensor location.

Conditions for Running the Diagnostics:
This diagnostic runs continuously when the keyswitch is in the ON position.

Conditions for Setting the Fault Codes:
The Engine Control Module (ECM) detected the OEM temperature sensor exceeded the engine protection limit.

Action Taken When the Fault Code is Active:
The ECM illuminates the red STOP ENGINE lamp immediately after the diagnostic runs and fails.

Conditions for Clearing the Fault Code:
1) To validate the repair, start the engine and let it idle for 1 minute.
2) The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.
3) The ECM will turn off the red STOP ENGINE lamp immediately after the diagnostic runs and passes.
4) The Reset All Faults command in INSITE™ electronic service tool can be used to clear active and inactive faults.

Shop Talk:
This fault code is activated when the temperature input from the OEM sensor exceeds the engine protection limit defined by the OEM. An engine power derate is possible depending on the OEM application.

Possible Causes:
1) Inactive fault codes
2) Faulty ECM