Low voltage on the +5 volt supply wire can be caused by a short circuit to ground in a supply wire, a short circuit between a supply wire and a return wire, a malfunctioning sensor, or a malfunctioning ECM power supply.
1)Replace the barometric pressure sensor.2)Replace the engine oil pressure sensor.3)Replace the digital vehicle speed sensor.4)Replace the remote accelerator position sensor.5)Repair or replace the engine harness.6)Replace the ECM.7)Replace the OEM harness.
Cummins ISX CM870 (2003-06) Fault Code: 343 PID: S254 SPN: 629 FMI: 12/12 Electronic Control Module Warning Internal Hardware Failure – Bad Intelligent Device or Component. ECM power supply errors have been detected.
Cummins ISX CM870 (2003-06) Fault Code: 341 PID: S253 SPN: 630 FMI: 2/2 Engine control module (ECM) data lost.
Cummins ISX CM870 (2003-06) Fault Code: 339 PID: S087 SPN: 1267 FMI: 4/4 Idle Shutdown Vehicle Accessories Relay Driver Circuit – Voltage Below Normal, or Shorted to Low Source. Low voltage detected at the idle shutdown vehicle accessory or ignition bus relay circuit when commanded ON.
Cummins ISX CM870 (2003-06) Fault Code: 338 PID: S087 SPN: 1267 FMI: 3/3 Idle Shutdown Vehicle Accessories Relay Driver Circuit – Voltage Above Normal, or Shorted to High Source. Open circuit or short to voltage source detected at the idle shutdown vehicle accessory/ignition bus relay circuit.
Cummins ISX CM870 (2003-06) Fault Code: 319 PID: P251 SPN: 251 FMI: 2/2 Real-Time Clock Power Interrupt – Data Erratic, Intermittent, or Incorrect. Real-time clock lost power.
Cummins ISX CM870 (2003-06) Fault Code: 295 PID: P108 SPN: 108 FMI: 2/2 Barometric Pressure – Data Erratic, Intermittent, or Incorrect. An error in the barometric pressure sensor signal was detected by the ECM.