2.2.218. SPN 4346, FMI 5, DEF pressure line heater: Heater open circuit.ΒΆ

Description

The EEM4 monitoring system has detected an open load on the DEF pressure line heater control circuit.

Possible causes are:

  • The DEF pressure line heater wiring is defective.
  • The DEF heater relay is defective.
  • The DEF pressure 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 pressure line heater wiring, the connectors and the contact surfaces of the connector pins (possible oxidation). Measure cable from relay to ECU to detect faulty cable.
  • Examine the DEF heater relay wiring, the connectors and the contact surfaces of the connector pins (possible oxidation).
  • Measure cable from relay to ECU to detect faulty cable.
  • Try the operation with another DEF pressure line to see if the DEF pressure line is defective.