4.2.78. SPN 174, FMI 4, Fuel temperature sensor voltage below normalΒΆ

Description

The measured fuel temperature signal is below the normal operating range.

Possible causes are:

  • The fuel temperature sensor wiring is defective.
  • The fuel temperature sensor is defective.

Reaction in EEM

The FC is stored and the warning lamp is activated. Engine power will be reduced (Degradation Level 1). The CAN message indicates active fault. Engine functions that depend on the fuel temperature are not active.

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 fuel temperature sensor wiring, the connectors and the contact surfaces of the connector pins (possible oxidation).
  • Check the operation with another fuel temperature sensor to see if the fuel temperature sensor is defective.

See Fuel temperature sensor sensor for reference.