Cummins ISB CM850 (2003-06) Fault Code: 2376 PID: 412 SPN: 412 FMI: 2 Recirculation Exhaust Gas (EGR) Temperature Sensor Circuit – Voltage Below Normal or Shorted to Low Source. Low signal voltage detected at the EGR temperature circuit.

This fault code is set active if the sensor signal voltage is below the normal operating range for the sensor and the electronic control module (ECM) has commanded the EGR valve open. This fault code will not be set active if the ECM has commanded the EGR valve closed. However, once the fault code is set, it will remain active independent of whether the EGR valve is open or closed.

The EGR temperature sensor shares return wires in the engine harness with other sensors. An shorted return can cause multiple fault codes to be active. Before troubleshooting Fault Code 2376, check for multiple fault codes.

Possible causes:

1)Signal shorted to ground in the harness or ECM
2)Signal shorted to return or ground in the sensor.

Possible repairs:

1)Replace the EGR temperature sensor.
2)Repair or replace the engine harness.
3)Replace the ECM.