3.2.88. SPN 174, FMI 0, Fuel inlet temperature high, ALARM (>85°C)

Description

The measured fuel temperature rises above the warning limit (+85°C). Possible causes for the high temperature indication are:

  • The fuel in the tank is too hot.
  • 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 (FL1). The CAN message indicates active fault.

Solution

Find cause for the high fuel temperature indication:

  • Check the temperature of the fuel in the tank. ( Contact the vehicle’s manufacturer.)
  • If the tank is almost empty and the ambient temperature is high, the temperature may rise due to hot fuel return. (Contact the vehicle’s manufacturer.)

To check the electrical defects, check the fuel inlet temperature sensor, the sensor wiring and the controller input: 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 inlet temperature sensor to see if the fuel inlet temperature sensor is defective.

See Fuel temperature sensor for reference.