2.2.242. SPN 4376, FMI 31, DEF pump direction valve: Low side ECU power stage over temperatureΒΆ

Description

The EEM monitoring system has detected over temperature on the DEF pump direction valve low side powerstage.

Possible causes are:

  • The DEF supply module direction valve wiring is defective.
  • The DEF supply module is defective.
  • The control unit is defective.

Reaction in EEM

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

NOTE: The present fault is classified as an emission related fault. Engine power is reduced after a certain time defined by an authority.

Solution

First save the error log and then do the procedure that follows:

  • Examine the DEF supply module direction valve wiring, the connectors and the contact surfaces of the connector pins (possible oxidation).
  • Test the operation with another DEF supply module to see if the supply module is defective.
  • Test the ECU operation with another EEM controller. If the system is functional and the fault is not active with the replacement ECU, then the original ECU is defective.

See Supply module sensor for reference.