4.2.338. SPN 977, FMI 6, Fan control output current above normalΒΆ

Description

The measured fan control output current is above the normal operating range.

Possible causes are:

  • The fan wiring is defective (Short circuit)
  • The fan is defective
  • The control unit 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.
  • Check the ECU operation with another EEM4 controller. If the system is functional and the fault is not active with the replacement ECU, then the original ECU is defective.