Cummins ISB CM850 (2003-06) Fault Code: 245 PID: SID 33 SPN: 647 FMI: 4 Fan Control Circuit – Voltage Below Normal or Shorted to Low Source. Low signal voltage detected at the fan control circuit when commanded on.

Cummins ISB CM850 (2003-06) Fault Code: 245 PID: SID 33 SPN: 647 FMI: 4 Fan Control Circuit – Voltage Below Normal or Shorted to Low Source. Low signal voltage detected at the fan control circuit when commanded on.

The fan control logic can be adjusted with the INSITE? electronic service tool. There are two choices: 12 or 24 VDC ON, or 0 VDC ON. For proper fan operation, the fan control logic setup with INSITE? electronic service tool must match the hardware configuration on the vehicle.

This fault code is logged when the ECM commands 12 or 24 VDC to the fan control solenoid, but the voltage on the fan control signal circuit is less than 12 or 24 VDC. The low voltage on the signal circuit usually indicates a short circuit to ground in the harness or solenoid.

If Fault Code 245 is still active after completing the following troubleshooting steps, consult the OEM service literature for procedures to check the fan control circuit for a short circuit to ground.

Possible repairs:

1)Replace the fan control solenoid.
2)Repair or replace the OEM harness.
3)Replace the ECM.