2.2.150. SPN 3361, FMI 31, DEF dosing valve: ECU power stage over temperatureΒΆ

Description

The EEM monitoring system has detected over temperature on the DEF dosing valve powerstage.

Possible causes are:

  • The DEF dosing valve wiring is defective.
  • The DEF dosing valve 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.

Solution

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

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