AIR CONDITIONING SYSTEM(for Automatic Air Conditioning System), Diagnostic DTC:B1411/11

DTC Code DTC Name
B1411/11 Room Temperature Sensor Circuit

DESCRIPTION

The cooler thermistor (room temperature sensor) for the front seat is installed in the instrument panel to detect the room temperature and control the heater and air conditioner auto mode. The resistance of the room temperature sensor changes in accordance with the front room temperature. As the temperature decreases, the resistance increases. As the temperature increases, the resistance decreases.

The air conditioning amplifier assembly applies voltage (5 V) to the room temperature sensor and reads voltage changes as the resistance of the room temperature sensor changes. This sensor also sends the appropriate signals to the air conditioning amplifier assembly.

DTC No. DTC Detection Condition Trouble Area
B1411/11 An open or short in the cooler thermistor (room temperature sensor) circuit.

  • Cooler thermistor (room temperature sensor)

  • Harness or connector

  • Air conditioning amplifier assembly

WIRING DIAGRAM

A005KE8E27
*a COOLER THERMISTOR (ROOM TEMPERATURE SENSOR)
*b AIR CONDITIONING AMPLIFIER ASSEMBLY

PROCEDURE


  1. READ VALUE USING INTELLIGENT TESTER (ROOM TEMPERATURE SENSOR)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the intelligent tester on.

    4. Enter the following menus: Body / Air Conditioner / Data List.

    5. According to the display on the intelligent tester, read the Data List.

      Air Conditioner
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Room Temperature Sensor

      Cooler thermistor (room temperature sensor) /

      Min.: -6.5°C (20.3°F)

      Max.: 57.25°C (135.1°F)

      		 Actual room temperature for front seat displayed

      Open in the circuit: -6.5°C (20.3°F)

      Short in the circuit: 57.25°C (135.1°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 COOLER THERMISTOR (ROOM TEMPERATURE SENSOR) Click here

    A

  2. CHECK FOR DTC


    1. Clear the DTCs Click here.

    2. Check for DTCs Click here.

      OK
      DTC B1411 is not output

    OK

    END

    NG

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

  3. INSPECT COOLER THERMISTOR (ROOM TEMPERATURE SENSOR)


    1. Remove the cooler thermistor (room temperature sensor) Click here.

    2. Inspect the cooler thermistor (room temperature sensor) Click here.


    NG

    REPLACE COOLER THERMISTOR (ROOM TEMPERATURE SENSOR) Click here

    OK

  4. CHECK HARNESS AND CONNECTOR (ROOM TEMPERATURE SENSOR - AIR CONDITIONING AMPLIFIER)


    1. Disconnect the F33 cooler thermistor (room temperature sensor) connector.

    2. Disconnect the F42 air conditioning amplifier 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
      F33-1 (ST+) - F42-29 (TR) Always Below 1 Ω
      F33-2 (ST-) - F42-34 (SG-1) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      F33-1 (ST+) - Body ground Always 10 kΩ or higher
      F33-2 (ST-) - Body ground Always 10 kΩ or higher

    OK

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR