4.2.336. SPN 977, FMI 3, Fan control output short circuit to high SOURCEΒΆ

Description

EEM4 monitoring system has detected short circuit on fan control output.

Possible causes are:

  • The fan wiring is defective (Shorted to high source.)
  • The fan is defective

Reaction in EEM

The FC is stored and the warning lamp is activated. The CAN message indicates active fault.

Solution

First save the error log and then erase it. Restart the ECU after erasing the error log. If the fault occurs again during the next driving cycle, check the following paths:

  • Check the fan control wiring, the connectors and the contact surfaces of the connector pins (possible oxidation).
  • Check the fan operation.