At key-on, before the engine starts, the sensor readings for barometric pressure, exhaust gas pressure, and engine oil pressure are compared with the intake manifold pressure. This fault code occurs if the intake manifold pressure sensor reading is different from any two of the other three. This check is only done once after the keyswitch is turned on and before the engine is started. The engine oil temperature must also be at least 7?C [45?F] for the check to run.
Shop exhaust fans can cause his fault code to come active. Turn exhaust fans off when troubleshooting this fault code.
1)Replace the intake manifold pressure sensor.
Cummins ISX CM870 (2003-06) Fault Code: 432 PID: S230 SPN: 558 FMI: 13/13 Accelerator Pedal Idle Validation Circuit – out of calibration. Voltage at idle validation on-idle and off-idle circuit does not match accelerator pedal position.
Cummins ISX CM870 (2003-06) Fault Code: 431 (SSS) PID: S230 SPN: 558 FMI: 2/2 Accelerator Pedal Idle Validation Circuit – data incorrect. Voltage detected simultaneously on both idle validation and off-idle validation switches.
Cummins ISX CM870 (2003-06) Fault Code: 431 (ISS) PID: S230 SPN: 558 FMI: 2/2 Accelerator Pedal Idle Validation Circuit – data incorrect. Voltage detected simultaneously on both idle validation and off-idle validation switches.
Cummins ISX CM870 (2003-06) Fault Code: 431 (NISS) PID: S230 SPN: 558 FMI: 2/2 Accelerator Pedal Idle Validation Circuit – data incorrect. Voltage detected simultaneously on both idle validation and idle validation off-idle validation switches.
Cummins ISX CM870 (2003-06) Fault Code: 429 PID: P097 SPN: 97 FMI: 4/4 Water-in-Fuel Indicator Sensor Circuit – Voltage Below Normal or Shorted to Low Source. Low voltage detected at the water-in-fuel circuit.
Cummins ISX CM870 (2003-06) Fault Code: 428 PID: P097 SPN: 97 FMI: 3/3 Water-in-Fuel Indicator Sensor Circuit – Voltage Above Normal or Shorted to High Source. High voltage detected at the water-in-fuel circuit.