Cummins ISX CM870 (2003-06) Fault Code: 689 PID: P190 SPN: 190 FMI: 2/2 Engine Crankshaft Speed/Position – Data Erratic, Intermittent, or Incorrect. The ECM has detected an error in the engine speed signal.

Description

This fault is logged when the ECM does not receive a valid engine speed signal.

Possible causes:

1)Open or short circuit of the +5 volt supply, signal, or return wire in the engine harness
2)Damaged or malfinctioning engine speed sensor.

Possible repairs:

1)Replace the engine speed sensor.
2)Inspect the crankshaft tone wheel/gear teeth for damage or spinning.
3)Replace the ECM.
4)Repair or replace the engine harness.