2.2.199. SPN 4337, FMI 8, DEF pump temperature: Signal duty cycle in failure rangeΒΆ

Description

The measured DEF pump temperature signal signal not in range or erroneous signal.

Possible causes are:

  • The DEF supply module wiring is defective. (Shorted to high source or open circuit.)
  • The DEF supply module is defective.

Reaction in EEM

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

The SCR system might be unable to dose and the engine will derate when the emissions are exceeded due to the SCR system malfunction.

Solution

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

  • Examine the DEF supply module wiring, the connectors and the contact surfaces of the connector pins (possible oxidation).
  • Test Check the operation with another DEF supply module to see if the supply module is defective.

See Supply module sensor for reference.