Cummins ISB CM850 (2003-06) Fault Code: 122 PID: 102 SPN: 102 FMI: 3 Intake Manifold Pressure Sensor Circuit – Voltage Above Normal or Shorted to High Source. High signal voltage detected at the intake manifold pressure circuit. The intake manifold pressure sensor shares SUPPLY and RETURN wires in the engine harness with other sensors. Opens and shorts in the engine harness can cause multiple fault codes to be active. Before troubleshooting Fault Code 122, check for multiple faults. Possible causes: 1)Open return circuit in the engine harness, connectors, or sensor2)SIGNAL wire shorted to sensor supply or battery voltage. The sensor...

Cummins ISB CM850 (2003-06) Fault Code: 1228 PID: 27 SPN: 27 FMI: 2 EGR Valve Position – Data erratic, intermittent, or incorrect. Intermittent EGR position information is being received by the electronic control module (ECM). This fault code is caused by an internal failure of the EGR valve position sensor. This failure causes erratic readings of EGR valve position. Possible repairs: 1)Replace the EGR position sensor. Cummins ISB CM850 (2003-06) Fault Code: 1145 PID: SID 6 SPN: 656 FMI: 7 Injector Solenoid Driver Cylinder 6 – Mechanical System Not Responding Properly or Out of Adjustment. Unintended fueling detected in cylinder...

Cummins ISB CM850 (2003-06) Fault Code: 1229 PID: SID 27 SPN: 2795 FMI: 2 VGT Position Sensor – Data erratic, intermittent, or incorrect. Intermittent variable geometry turbocharger (VGT) position information is being received by the electronic control module (ECM). This fault code is caused by an internal failure of the variable geometry turbocharger (VGT) position sensor. This failure causes erratic readings of variable geometry turbocharger (VGT) position. Possible repairs: 1)Replace the turbocharger position sensor.2)Replace the ECM. Cummins ISB CM850 (2003-06) Fault Code: 1228 PID: 27 SPN: 27 FMI: 2 EGR Valve Position – Data erratic, intermittent, or incorrect. Intermittent EGR...

Cummins ISB CM850 (2003-06) Fault Code: 123 PID: 102 SPN: 102 FMI: 4 Intake Manifold Pressure Sensor Circuit – Voltage Below Normal or Shorted to Low Source. Low signal voltage detected at the intake manifold pressure circuit. The intake manifold pressure sensor shares SUPPLY and RETURN wires in the engine harness with other sensors. Opens and shorts in the engine harness can cause multiple fault codes to be active. Before troubleshooting Fault Code 123, check for multiple faults. Possible causes: 1)Signal circuit open or shorted to ground in the engine harness or sensor2)SUPPLY line open or shorted to ground. The...

Cummins ISB CM850 (2003-06) Fault Code: 1239 PID: SPN: 2623 FMI: 3 Accelerator Pedal or Lever Position Sensor 2 Circuit – Voltage Above Normal or Shorted to High Source. High voltage detected at accelerator pedal position number 2 signal circuit. Newer engines use two throttle position sensors to determine the throttle position. Older throttle pedals used a single throttle position sensor and an idle validation switch. If Fault Codes 132 and 1241 are active when the accelerator pedal is in the idle position and Fault Code 132 goes inactive and Fault Code 1239 goes active when the throttle is depressed,...