Cummins ISB6.7 CM2150 (2007-09) Fault Code: 331 PID: SID 002 SPN: 652 FMI: 5 Injector Solenoid Driver Cylinder 2 Circuit – Current Below Normal or Open Circuit. High resistance or no current detected at cylinder 2 injector supply or return pin.

Verify the electronic control module (ECM) calibration is correct. Check the calibration revision history found on QuickServe™ Online for applicable fixes to the calibration stored in the ECM. If necessary, calibrate the ECM.

1)Fault activation: The ECM senses current as each injector is actuated. If the ECM detects a persistent circuit error on an injector circuit, this fault will become active. If a circuit error is determined to cause excessive current, the ECM will disable the injection event for the cylinder(s) that is faulty.
2)Fault deactivation: The ECM will attempt to enable any disabled injector circuit whenever the engine is started and approximately once per minute while the engine is running. If an injector circuit fault is active and the faulty condition is repaired, the fault will become inactive once the engine is restarted or if the engine is permitted to idle for more than 1 minute.
3)If a fault condition is intermittent and especially if more than one injector fault code is in the ECM memory, look for a wire harness that can short to components inside the rocker housing or for a short circuit to ground in the injector solenoid.
4)If more than one injector fault code is occurring and the faults occur for injector circuits in the same bank, a short circuit exists.

Causes of a single injector fault are:

1)An open circuit in the engine harness(es) or injector solenoid
2)High resistance in a single injector or injector solenoid
3)Extremely low resistance in an injector solenoid (injector shorted internally but not to ground)
4)Damaged ECM.
5)If a fault condition is intermittent and especially if more than one injector fault code is in the ECM memory, look for a wire harness that can short to components inside the rocker housing or a short circuit to ground in the injector solenoid.

Causes of multiple injector fault codes in the same bank of injectors are:

1)Short circuit in the engine harness(es) – either shorts to ground or to other wires in the engine harness
2)Short circuit in any of the three injectors in the bank – shorts to ground
3)Damaged ECM.

Possible repairs:

1)Repair or replace the engine harness.
2)Repair or replace the injector harness.
3)Repair or replace the damaged component.
4)Replace the ECM.
5)Replace injector number 1.
6)Replace injector number 2.
7)Replace injector number 3.