Cummins ISM CM875 (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.
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.