4.2.229. SPN 520239, FMI 5, DEF dosing valve after cooler current below normal or open circuitΒΆ

Description

DEF dosing valve after cooler current is below the normal operating range.

Possible causes are:

  • The DEF dosing valve after cooler wiring is defective. (Open circuit)
  • The DEF dosing valve after cooler 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 DEF dosing valve after cooler wiring, the connectors and the contact surfaces of the connector pins (possible oxidation). Measure between the after cooler and the ECU to detect the faulty cable.
  • Check the operation with another DEF dosing valve after cooler to see if the after cooler is defective.