ECD SYSTEM, Diagnostic DTC:P0180

DTC Code DTC Name
P0180 Fuel Temperature Sensor "A" Circuit

DESCRIPTION

The fuel temperature sensor senses the fuel temperature. A thermistor built into the sensor changes the resistance value according to the fuel temperature. The lower the fuel temperature, the greater the thermistor resistance value, and the higher the fuel temperature, the lower the thermistor resistance value (See Fig. 1).

The fuel temperature sensor is connected to the ECM. The 5 V power source voltage in the ECM is applied to the fuel temperature sensor from terminal THF via a resistor R. That is, resistor R and the fuel temperature sensor are connected in series. When the resistance value of the fuel temperature sensor changes in accordance with changes in the fuel temperature, the potential at the terminal THF also changes. Based on this signal, the ECM increases the fuel injection volume to improve driveability during low engine revolution and high fuel temperature.

A003F9HE01
DTC No. DTC Detection Condition Trouble Area
P0180 Open or short in fuel temperature sensor circuit for 0.5 seconds or more.
  • Open or short in fuel temperature sensor circuit

  • Fuel temperature sensor

  • ECM

WIRING DIAGRAM

A003FNKE10

INSPECTION PROCEDURE

Tech Tips

Read freeze frame data using the GTS. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, and other data from the time the malfunction occurred.

PROCEDURE


  1. READ VALUE USING GTS (FUEL TEMPERATURE)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON and turn the GTS on.

    3. Enter the following menus: Powertrain / Engine and ECT / Data List / Fuel Temperature.

    4. Read the value.

      Result
      Display Proceed
      -40°C (-40°F) A
      140°C (284°F) or more B
      The same as actual fuel temperature C

      Tech Tips


      • If there is an open circuit, the GTS indicates -40°C (- 40°F).

      • If there is a short circuit, the GTS indicates 140°C (284°F) or higher.


    B
    C
    A
  2. CHECK HARNESS AND CONNECTOR (CHECK FOR OPEN)


    1. A003ICRE33
      Text in Illustration
      *1 Fuel Temperature Sensor
      *2 ECM
      *a

      Front view of wire harness connector

      (to Fuel Temperature Sensor)

      Disconnect the fuel temperature sensor connector.

    2. Connect terminals 2 and 1 of the fuel temperature sensor connector.

    3. Connect the GTS to the DLC3.

    4. Turn the ignition switch to ON and turn the GTS on.

    5. Enter the following menus: Powertrain / Engine and ECT / Data List / Fuel Temperature.

    6. Read the value.

      OK
      140°C (284°F) or higher

    NG
    OK
  3. CHECK HARNESS AND CONNECTOR (ECM - FUEL TEMPERATURE SENSOR)


    1. Disconnect the fuel temperature sensor connector.

    2. Disconnect the ECM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      D46-2 - D100-72 (THF) Always Below 1 Ω
      D46-1 - D100-95 (ETHF) Always Below 1 Ω

    NG
    OK
  4. CHECK HARNESS AND CONNECTOR (CHECK FOR SHORT)


    1. A003BL1E01
      Text in Illustration
      *1 Fuel Temperature Sensor
      *2 ECM

      Disconnect the fuel temperature sensor connector.

    2. Connect the GTS to the DLC3.

    3. Turn the ignition switch to ON and turn the GTS on.

    4. Enter the following menus: Powertrain / Engine and ECT / Data List / Fuel Temperature.

    5. Read the value.

      OK
      -40°C (-40°F)
    6. Reconnect the fuel temperature sensor connector.


    NG
    OK
  5. CHECK HARNESS AND CONNECTOR (ECM - FUEL TEMPERATURE SENSOR)


    1. Disconnect the fuel temperature sensor connector.

    2. Disconnect the ECM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      D46-2 or D100-72 (THF) - Body ground Always 10 kΩ or higher

    NG
    OK