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 temperature switch that is connected to the combination meter assembly via a direct line.

DTC No. Detection Item DTC Detection Condition Trouble Area Memory Note
B1503 Exhaust Heat Management Warning Detected

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


  • Temperature switch circuit open or shorted

  • Temperature is 120°C (248°F) or more

  • Harness or connector

  • Temperature switch

  • Combination meter assembly

 DTC stored -

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 temperature switch which is used for the SFI system.

WIRING DIAGRAM

A01TDGTE01
*a Temperature Switch
*b Combination Meter Assembly

PROCEDURE


  1. READ VALUE USING GTS (COOLANT TEMPERATURE)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

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

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


      Body Electrical > Combination Meter > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Coolant Temperature Engine coolant temperature Min.: 0°C (32°F), Max.: 127.5°C (261.5°F) 75 to 100°C (167 to 212°F) (After warming up engine) -

      Body Electrical > Combination Meter > Data List
      Tester Display
      Coolant Temperature

      Tech Tips


      • The 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.
      Result
      Proceed to
      OK
      NG

    NG

    GO TO EXHAUST HEAT RECIRCULATION SYSTEM Click here

    OK

  2. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - TEMPERATURE SWITCH)


    1. Disconnect the E46 combination meter assembly connector.

    2. Disconnect the A119 temperature switch connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      E46-29 (TWS2) - A119-2 (TWS2) Always Below 1 Ω
      A119-1 (GND) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. REPLACE TEMPERATURE SWITCH


    1. Replace the temperature switch with a new or known good one.

      Click here

      OK
      DTC B1503 is not output.
      Result
      Proceed to
      OK
      NG

    OK

    END

    NG

    REPLACE COMBINATION METER ASSEMBLY for Hatchback, Wagon: Click here
    REPLACE COMBINATION METER ASSEMBLY for Sedan: Click here