Cummins ISB CM850 (2003-06) Fault Code: 551 (ISS) PID: SID 230 SPN: 558 FMI: 4 Accelerator Pedal or Lever Idle Validation Circuit – Voltage Below Normal or Shorted to Low Source. No voltage detected simultaneously on both the idle validation and off-idle and on-idle switches.
1)This fault code is usually caused by a short circuit to ground in the harness, an uncalibrated accelerator pedal or lever assembly, or a miswired idle validation switch.
2)When installing a new accelerator pedal or lever assembly, it must be calibrated before operating the engine. To calibrate, turn the keyswitch to the ON position, and fully depress and release the pedal or lever three times.
1)Replace the ISS switch.
2)Repair or replace the OEM harness.
3)Replace the ECM.
4)Replace the ISS.
Cummins ISB CM850 (2003-06) Fault Code: 545 PID: SID 32 SPN: 1188 FMI: 7 Turbocharger 1 Wastegate Control ? Mechanical System Not Responding Properly or Out of Adjustment. Intake manifold pressure has exceeded the maximum limit for the given engine rating.
Cummins ISB CM850 (2003-06) Fault Code: 529 PID: SID 51 SPN: 703 FMI: 3 Auxiliary Input/Output 3 Circuit – Voltage Above Normal, or Shorted to High Source. High signal voltage has been detected at the auxiliary input/output 3 circuit.
Cummins ISB CM850 (2003-06) Fault Code: 528 PID: 93 SPN: 93 FMI: 2 Auxiliary Alternate Torque Validation Switch – Data Erratic, Intermittent, or Incorrect. An error has been detected in the alternate torque switch circuit.
Cummins ISB CM850 (2003-06) Fault Code: 527 PID: SID 154 SPN: 702 FMI: 3 Auxiliary Input/Output 2 Circuit Voltage Above Normal or Shorted to High Source. High signal voltage or open circuit has been detected at the auxiliary input and output 2 circuit.
Cummins ISB CM850 (2003-06) Fault Code: 523 PID: 89 SPN: 611 FMI: 2 Auxiliary Intermediate (PTO) Speed Switch Validation – Data Erratic, Intermittent, or Incorrect. The position of the intermediate speed control switch 1 does not match the position of the intermediate speed control validation switch.
Cummins ISB CM850 (2003-06) Fault Code: 499 PID: 98 SPN: 98 FMI: 4 Engine Oil Level Sensor Circuit – Voltage Below Normal or Shorted to Low Source. The engine oil level sensor has detected an internal failure.
