Cummins ISB CM850 (2003-06) Fault Code: 319 PID: 251 SPN: 251 FMI: 2 Real-Time Clock Power Interrupt – Data Erratic, Intermittent or Incorrect. Real-time clock lost power.

Cummins ISB CM850 (2003-06) Fault Code: 319 PID: 251 SPN: 251 FMI: 2 Real-Time Clock Power Interrupt – Data Erratic, Intermittent or Incorrect. Real-time clock lost power.

This fault indicates that the real-time clock in the ECM lost power. Possible causes for this fault are weak or failed real-time clock battery, failed wiring or connectors between the battery and ECM, or the engine is not equipped with a real-time clock battery and the vehicle battery power to the ECM is lost.

NOTE:If the Real Time Clock is supplied by the OEM via a CAN BUS and a battery backup is not used, then refer to the OEM wiring diagram. If this is the case, then check INSITE? electronic service tool, ?Advanced ECM Data – Real Time Clock Settings.? If the OEM supplies a Real Time Clock signal, then the address must be set according to the OEM wiring or the fault code will become active.

Possible repairs:

1)Replace the engine harness.
2)Repair or replace the real-time clock battery.