Cummins ISM CM875 (2003-06) Fault Code: 2311 PID: S18 SPN: 633 FMI: 11/31 Fueling Actuator Number 1 Circuit Error. Error detected on the front fueling actuator circuit.

Possible causes:

1)Open circuit in the engine harness, connectors, or actuator
2)Short circuit to ground in the engine harness or actuator
3)Short circuit to voltage source in the engine harness
4)Low or high resistance in the actuator.

Possible repairs:

1)Replace the fueling actuator.
2)Repair or replace the engine harness.
3)Replace the ECM.