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

-
Tip:

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

E262503E01

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. Read the Data List according to the display on the GTS.

      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)

      except 1WW:

      75 to 100 °C (167 to 212°F): After warming up engine

      for 1WW:

      75 to 90°C (167 to 194°F): After warming up engine

      -

      Body Electrical > Combination Meter > Data List

      Tester Display

      Coolant Temperature
      Tip:

      • 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

    for Sedan:Click hereClick here