Lexus IS250 IS220d GSE20 ALE20 2AD-FHV ENGINE CONTROL SYSTEM

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

READ VALUE OF FUEL TEMPERATURE SENSOR

CHECK FUEL TEMPERATURE SENSOR (OPEN IN SENSOR)

CHECK HARNESS AND CONNECTOR (FUEL TEMPERATURE SENSOR - ECM)

CHECK FUEL TEMPERATURE SENSOR (SHORT IN SENSOR)

CHECK HARNESS AND CONNECTOR (FUEL TEMPERATURE SENSOR - ECM)

DTC P0180 Fuel Temperature Sensor "A" Circuit

DTC P0182 Fuel Temperature Sensor "A" Circuit Low Input

DTC P0183 Fuel Temperature Sensor "A" Circuit High Input

DESCRIPTION

The fuel temperature sensor monitors the fuel temperature. The fuel temperature sensor has a thermistor that varies its resistance depending on the fuel temperature. When the fuel temperature is low, the resistance of the thermistor is high. When the temperature is high, the resistance is low. The variations of resistance are communicated to the ECM as changes of voltage (see Fig. 1).


The fuel temperature sensor is connected to the ECM (see below). The 5 V power source voltage in the ECM is applied to the fuel temperature sensor from terminal THF via resistor R.


The resistor R and fuel temperature sensor are connected in series. When the resistance value of the fuel temperature sensor changes due to a change in fuel temperature, the voltage at terminal THF also changes. Based on this signal, the ECM corrects the pressure control compensation of the supply pump and determines errors.


Dtc P0180  Fuel Temperature Sensor A Circuit. 2AD-FHV ENGINE CONTROL SYSTEM. Lexus IS250 IS220d GSE20 ALE20
DTC No.DTC Detection ConditionTrouble Area
P0180 Open or short in fuel temperature sensor circuit for 0.5 seconds
(1 trip detection logic)
Open or short in fuel temperature sensor circuit
Fuel temperature sensor
ECM
P0182 Short in fuel temperature sensor circuit for 0.5 seconds
(1 trip detection logic)
Open or short in fuel temperature sensor circuit
Fuel temperature sensor
ECM
P0183 Open in fuel temperature sensor circuit for 0.5 seconds
(1 trip detection logic)
Open or short in fuel temperature sensor circuit
Fuel temperature sensor
ECM

WIRING DIAGRAM

Dtc P0180  Fuel Temperature Sensor A Circuit. 2AD-FHV ENGINE CONTROL SYSTEM. Lexus IS250 IS220d GSE20 ALE20

INSPECTION PROCEDURE

  • NOTICE:
  • After replacing the ECM, the new ECM needs registration and initialization .
  • HINT:
  • If DTCs relating to different systems are output, and they share terminal E2 as their ground, check this ground circuit first.
1.READ VALUE OF FUEL TEMPERATURE SENSOR

Connect the intelligent tester to the DLC3.

Turn the engine switch ON (IG) and turn the intelligent tester ON.

Enter the following menus "Powertrain / Engine / Data List / Fuel Temp" and read its value displayed on the intelligent tester.

  • Temperature:
  • Same value as the actual fuel temperature.
  • Result:
  • Temperature DisplayedProceed to
    -40°C (-40°F)A
    140°C (284°F) or moreB
    OK (Same as actual fuel temperature)C
  • HINT:
If there is an open circuit, the intelligent tester indicates -40°C (-40°F).
If there is a short circuit, the intelligent tester indicates 140°C (284°F) or more.
B
Go to step 4
C
CHECK FOR INTERMITTENT PROBLEMS
A
2.CHECK FUEL TEMPERATURE SENSOR (OPEN IN SENSOR)
Dtc P0180  Fuel Temperature Sensor A Circuit. 2AD-FHV ENGINE CONTROL SYSTEM. Lexus IS250 IS220d GSE20 ALE20

Disconnect the E69 fuel temperature sensor connector.

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

Connect the intelligent tester to the DLC3.

Turn the engine switch ON (IG) and turn the intelligent tester ON.

Enter the following menus "Powertrain / Engine / Data List / Fuel Temp" and read its value displayed on the intelligent tester.

  • Standard:
  • 140°C (284°F) or more

Reconnect the fuel temperature sensor connector.

OK
REPLACE FUEL TEMPERATURE SENSOR
NG
3.CHECK HARNESS AND CONNECTOR (FUEL TEMPERATURE SENSOR - ECM)
Dtc P0180  Fuel Temperature Sensor A Circuit. 2AD-FHV ENGINE CONTROL SYSTEM. Lexus IS250 IS220d GSE20 ALE20

Disconnect the E69 fuel temperature sensor connector.

Disconnect the E59 ECM connector.

Measure the resistance.

  • Standard resistance:
  • Tester ConnectionsSpecified Conditions
    THF (E69-2) - THF (E59-112)Below 1 Ω
    EHTF (E69-1) - ETHF (E59-89)

Reconnect the fuel temperature sensor connector.

Reconnect the ECM connector.

NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK
REPLACE ECM
4.CHECK FUEL TEMPERATURE SENSOR (SHORT IN SENSOR)
Dtc P0180  Fuel Temperature Sensor A Circuit. 2AD-FHV ENGINE CONTROL SYSTEM. Lexus IS250 IS220d GSE20 ALE20

Disconnect the E69 fuel temperature sensor connector.

Connect the intelligent tester to the DLC3.

Turn the engine switch ON (IG) and turn the intelligent tester ON.

Enter the following menus "Powertrain / Engine / Data List / Fuel Temp" and read its value displayed on the intelligent tester.

  • Standard:
  • -40°C (-40°F)

Reconnect the fuel temperature sensor connector.

OK
REPLACE FUEL TEMPERATURE SENSOR
NG
5.CHECK HARNESS AND CONNECTOR (FUEL TEMPERATURE SENSOR - ECM)
Dtc P0180  Fuel Temperature Sensor A Circuit. 2AD-FHV ENGINE CONTROL SYSTEM. Lexus IS250 IS220d GSE20 ALE20

Disconnect the E69 fuel temperature sensor connector.

Disconnect the E59 ECM connector.

Measure the resistance.

  • Standard resistance:
  • Tester ConnectionsSpecified Conditions
    THF (E69-2) or THF (E59-112) - Body ground10 kΩ or higher

Reconnect the fuel temperature sensor connector.

Reconnect the ECM connector.

NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK
REPLACE ECM