Cummins ISB CM850 (2003-06) Fault Code: 779 PID: SID 51 SPN: 703 FMI: 11 Auxiliary Equipment Sensor Input #3 (OEM Switch) – Root Cause Not Known.

Cummins ISB CM850 (2003-06) Fault Code: 779 PID: SID 51 SPN: 703 FMI: 11 Auxiliary Equipment Sensor Input #3 (OEM Switch) – Root Cause Not Known.

This fault code is activated when the pressure or 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 repairs:

1)Replace the OEM harness.