Cummins ISB CM850 (2003-06) Fault Code: 2556 PID: SID 70 SPN: 729 FMI: 4 Intake Air Heater #1 Circuit – Voltage Below Normal or Shorted to Low Source. Low voltage detected at the intake air heater signal circuit.
Possible causes:
1)A shorted intake air heater relay
2)Intake air heater relay supply wire shorted to ground.
Possible repairs:
1)Replace the damaged intake air heater relay.
2)Repair or replace the OEM harness.
3)The removal and installation of the connector may correct the fault.
4)Replace the ECM.
Cummins ISB CM850 (2003-06) Fault Code: 2555 PID: SID 70 SPN: 729 FMI: 3 Intake Air Heater #1 Circuit – Voltage Above Normal or Shorted to High Source. High voltage detected at the intake air heater signal circuit.
Cummins ISB CM850 (2003-06) Fault Code: 2554 PID: 95 SPN: 1209 FMI: 2 Exhaust pressure sensor circuit – data erratic, intermittent, or incorrect. An error in the exhaust pressure sensor signal was detected by the ECM.
Cummins ISB CM850 (2003-06) Fault Code: 2448 PID: SPN: 111 FMI: 17 Coolant Level – Data Valid But Below Normal Operational Range – Least Severe Level. Low engine coolant level detected.
Cummins ISB CM850 (2003-06) Fault Code: 2388 PID: SID 269 SPN: 2795 FMI: 13 Variable Geometry Turbocharger actuator position failed automatic calibration procedure – out of calibration.
Cummins ISB CM850 (2003-06) Fault Code: 2387 PID: SID 146 SPN: 2975 FMI: 7 Turbocharger actuator motor – the mechanical system is not responding properly or is out of adjustment. Turbocharger actuator is not responding or is slow to respond.
Cummins ISB CM850 (2003-06) Fault Code: 2386 PID: SPN: 2975 FMI: 6 Turbocharger actuator motor circuit – current is above normal. Excessive current detected at the turbocharger actuator motor circuit.
