Cummins ISB CM850 (2003-06) Fault Code: 343 PID: SID 254 SPN: 629 FMI: 12 Engine Control Module Warning Internal Hardware Failure – Bad Intelligent Device or Component. This fault code can only be caused by an internal ECM problem. Repairs are not possible for the ECM. For Euro certified engines this fault code indicates that the Real Time Clock feature needs to re reset (if equipped). Possible repairs: 1)Replace the ECM. Cummins ISB CM850 (2003-06) Fault Code: 342 PID: SID 253 SPN: 630 FMI: 13 Electronic Calibration Code Incompatibility – Out of Calibration. An incompatable calibration between the primary and...

Cummins ISB CM850 (2003-06) Fault Code: 351 PID: SID 254 SPN: 627 FMI: 12 Injector Power Supply – Bad Intelligent Device or Component. The ECM measured injector boost voltage is low. This fault code will become active when the engine is running, the primary engine speed sensor signal is present, the battery charge is above a minimum threshold, and, at the same time, the measured injector power supply voltage is lower than the commanded injector power supply voltage. This fault code will become inactive whenever the keyswitch is turned on. This fault code will become inactive whenever the engine is...

Cummins ISB CM850 (2003-06) Fault Code: 352 PID: SID 212 SPN: 1079 FMI: 4 Sensor Supply Voltage Number 1 Circuit – Voltage Below Normal or Shorted to Low Source. Low voltage detected at sensor supply number 1 circuit. Low voltage on the (+) 5 volt supply line can be caused by a short circuit to ground in a supply line, a short circuit between a supply line and a return line, a failed sensor, or a failed ECM power supply. On-Board Diagnostics (OBD) Information (Euro 4 Certified Engines): 1)The ECM illuminates the malfunction indicator lamp (MIL) when the diagnostic runs...

Cummins ISB CM850 (2003-06) Fault Code: 386 PID: SID 212 SPN: 1079 FMI: 3 Sensor Supply Voltage number 1 Circuit – Voltage Above Normal or Shorted to High Source. High voltage detected at sensor supply number 1 circuit. High voltage on the sensor supply line can be caused by an individual sensor supply wire in the harness shorted to battery voltage or a failed ECM power supply. On-Board Diagnostics (OBD) Information (Euro 4 Certified Engines): 1)The ECM illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.2)The ECM turns OFF the malfunction indicator lamp (MIL) after 3 consecutive...

Cummins ISB CM850 (2003-06) Fault Code: 387 PID: SID 221 SPN: 1043 FMI: 3 Accelerator Pedal or Lever Position Sensor Supply Voltage Circuit – Voltage Above Normal or Shorted to High Source. High voltage detected at sensor supply circuit for the accelerator pedal or lever position sensor. This fault is logged when the ECM senses more than +5.25 volts on the accelerator pedal or lever position +5 volt supply line. This can be caused by a short circuit to a voltage source in the OEM harness or a short circuit to an actuator signal circuit that is greater than +5...