2.2.201. SPN 4340, FMI 31, DEF suction line heater: ECU power stage over temperature.ΒΆ

Description

The EEM4 monitoring system has detected over temperature on the DEF suction line heater power stage.

Possible causes are:

  • The DEF suction line heater wiring is defective.
  • The DEF heater relay is defective.
  • The DEF suction line 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 which is defined by an authority.

Solution

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

  • Examine the DEF suction line heater wiring, the connectors and the contact surfaces of the connector pins (possible oxidation).
  • Examine the DEF heater relay wiring, the connectors and the contact surfaces of the connector pins (possible oxidation).
  • Try the operation with another DEF suction line heater to see if the DEF suction line heater is defective.