3.2.420. SPN 522336, FMI 31, Fan control underspeed or no signal detectedΒΆ

Description

The EEM4 monitoring system has detected underspeed or a signal loss on the fan speed control.

Possible causes are:

  • The fan wiring is defective.
  • 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.