METER / GAUGE SYSTEM, Diagnostic DTC:B1503

DTC Code DTC Name
B1503 Exhaust Heat Management Warning Detected

DESCRIPTION

This DTC is stored when the combination meter assembly detects a malfunction in the engine coolant temperature sensor that is connected to the combination meter assembly via a direct line.

DTC No. DTC Detection Condition Trouble Area
B1503

When IG voltage is 9.5 V or more and the following conditions is detected:


  1. Engine coolant temperature sensor operation malfunction

  2. Engine coolant temperature sensor circuit open or short

  3. Engine coolant temperature is 120°C (248°F) or more

  • Harness or connector

  • Engine coolant temperature sensor

  • Combination meter assembly (No. 3 meter circuit plate)

Tech Tips

This DTC is for the engine coolant temperature sensor which is used to detect the engine coolant temperature for the exhaust heat recirculation system, not for the engine coolant temperature sensor which is used for the EFI system.

WIRING DIAGRAM

A0040YZE05

INSPECTION PROCEDURE

PROCEDURE


  1. READ VALUE USING GTS (COOLANT TEMPERATURE)


    1. Set the vehicle in maintenance mode using the GTS Click here.

    2. Connect the GTS to the DLC3.

    3. Turn the power switch on (IG).

    4. Turn the GTS on.

    5. Enter the following menus: Body Electrical / Combination Meter / Data List.

    6. Check the values by referring to the table below.

      Combination Meter
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Coolant Temperature Engine coolant temperature/-40 to 127.5°C (-40 to 261.5°F) After warming up: 75 to 100°C (167 to 212°F) -

      Tech Tips


      • The engine coolant temperature value in this inspection is the data sent from the engine coolant temperature sensor for the SFI system.

      • When the Data List values do not match, a signal output error of the ECM is suspected.

      OK
      Engine coolant temperature displayed on the GTS is 75 to 100°C (167 to 212°F) after warming up

    NG

    GO TO EXHAUST HEAT RECIRCULATION SYSTEM Click here

    OK

  2. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - ENGINE COOLANT TEMPERATURE SENSOR)


    1. Disconnect the G2 engine coolant temperature sensor connector.

    2. Disconnect the L23 combination meter assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G2-2 (TWS3) - L23-16 (TWS3) Always Below 1 Ω
      G2-1 (E2) - L23-9 (E2) Always Below 1 Ω
      G2-2 (TWS3) or L23-16 (TWS3) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. INSPECT ENGINE COOLANT TEMPERATURE SENSOR


    1. A0040O2E09
      Text in Illustration
      *a

      Component without harness connected

      (Engine Coolant Temperature Sensor)
      *b Resistance kΩ
      *c Temperature °C (°F)

      Remove the engine coolant temperature sensor Click here.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      2 (TWS3) - 1 (E2) Temperature is 20 °C (68°F) 2.32 to 2.59 kΩ
      2 (TWS3) - 1 (E2) Temperature is 80 °C (176°F) 0.310 to 0.326 kΩ

    NG

    REPLACE ENGINE COOLANT TEMPERATURE SENSOR Click here

    OK

    REPLACE NO. 3 METER CIRCUIT PLATE Click here