METER / GAUGE SYSTEM, Diagnostic DTC:B1509

DTC Code DTC Name
B1509 Open in Ambient Temperature Sensor Circuit

DESCRIPTION

The thermistor assembly is installed in the front part of the cooler condenser assembly to display the ambient temperature on the multi-information display in the combination meter assembly and to control the air conditioning auto mode. As the temperature decreases, the resistance increases. As the temperature increases, the resistance decreases.

The combination meter assembly applies a voltage (5 V) to the thermistor assembly and reads the voltage changes as changes in the resistance of the thermistor assembly.

DTC No. DTC Detection Condition Trouble Area
B1509 An open or short in the thermistor assembly circuit.

  • Thermistor assembly

  • Harness or connector

  • Combination meter assembly

WIRING DIAGRAM

A004HXQE05
*a THERMISTOR ASSEMBLY
*b COMBINATION METER ASSEMBLY

PROCEDURE


  1. READ VALUE USING GTS (AMBIENT TEMPERATURE SENSOR)


    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. According to the display on the GTS, read the Data List.

      Combination Meter
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Ambient Temperature

      Thermistor assembly /

      Min: -40.0°C (-40.0°F)

      Max: 87.5°C (189.5°F)

      		 Actual ambient temperature displayed

      Open in the circuit: -40.0°C (-40.0°F)

      Short in the circuit: 87.5°C (189.5°F)
      OK
      The display is as specified in the normal condition column.
      Result
      Result Proceed to
      OK (When troubleshooting according to the DTC) A
      OK (When troubleshooting according to problem symptoms table) B
      NG C

    B

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

    C

    INSPECT THERMISTOR ASSEMBLY Click here

    A

  2. CHECK FOR DTC


    1. Clear the DTCs Click here.

    2. Check for DTCs Click here.

      OK
      DTC B1509 is not output

    OK

    END

    NG

    REPLACE COMBINATION METER ASSEMBLY Click here

  3. INSPECT THERMISTOR ASSEMBLY


    1. Remove the thermistor assembly Click here.

    2. Inspect the thermistor assembly Click here.


    NG

    REPLACE THERMISTOR ASSEMBLY Click here

    OK

  4. CHECK HARNESS AND CONNECTOR (THERMISTOR ASSEMBLY - COMBINATION METER ASSEMBLY)


    1. Disconnect the A48 thermistor assembly connector.

    2. Disconnect the D7 combination meter assembly connector.

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

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      A48-1 - D7-24 (TAM) Always Below 1 Ω
      A48-2 - D7-25 (SG-) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      A48-1 - Body ground Always 10 kΩ or higher
      A48-2 - Body ground Always 10 kΩ or higher

    OK

    REPLACE COMBINATION METER ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR