This fault code can only be caused by an internal ECM problem.
Repairs are not possible for the ECM.
Cummins ISM CM875 (2003-06) Fault Code: 9121 PID: S146 SPN: 2791 FMI: 0/15 EGR Valve Actuator Over Temperature (Calculated) – Data Above Normal Range – least severe level.
Cummins ISM CM875 (2003-06) Fault Code: 2973 PID: P102 SPN: 102 FMI: 2/2 Intake Manifold Pressure – data incorrect. The ECM has detected an intake manifold pressure signal that is too high or low for current engine operating conditions.
Cummins ISM CM875 (2003-06) Fault Code: 2964 PID: P105 SPN: 105 FMI: 0/16 Intake Manifold 1 Temperature – Data Valid But Above Normal Operating Range – Least Severe Level. Intake manifold air temperature signal indicates intake manifold air temperature is above engine protection warning limit.
Cummins ISM CM875 (2003-06) Fault Code: 2963 PID: P110 SPN: 110 FMI: 0/16 Engine Coolant Temperature – Data Valid But Above Normal Operating Range – Least Severe Level. Engine coolant temperature is above the engine protection warning limit.
Cummins ISM CM875 (2003-06) Fault Code: 2962 PID: P412 SPN: 412 FMI: 0/16 Exhaust Gas Recirculation Temperature – Data Valid But Above Normal Operating Range – Moderately Severe Level. Exhaust gas recirculation (EGR) temperature has exceeded the engine protection limit.
Cummins ISM CM875 (2003-06) Fault Code: 2961 PID: P412 SPN: 412 FMI: 0/15 Exhaust Gas Recirculation Temperature – Data Valid But Above Normal Operating Range – Least Severe Level. Exhaust gas recirculation (EGR) temperature has exceeded the engine protection limit.