AIR CONDITIONING SYSTEM, Diagnostic DTC:B1411/11

DTC Code DTC Name
B1411/11 Room Temperature Sensor Circuit

DESCRIPTION

The front 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 front room temperature sensor and reads voltage changes as the resistance of the front room temperature sensor changes. This sensor also sends the appropriate signals to the air conditioning amplifier assembly.

DTC Code DTC Detection Condition Trouble Area
B1411/11 An open or short in the front room temperature sensor circuit.

  • Front room temperature sensor

  • Harness or connector between front room temperature sensor and air conditioning amplifier assembly

  • Air conditioning amplifier assembly

WIRING DIAGRAM

A01EPOUE01

INSPECTION PROCEDURE

PROCEDURE


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


    1. Use the Data List to check if the front room temperature sensor is functioning properly.

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

      Front room temperature sensor /

      Min.: -6.5°C (20.3°F)

      Max.: 57.25°C (135.05°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 (135.05°F).
      OK
      The display is as specified in the normal condition.

    NG

    INSPECT FRONT ROOM TEMPERATURE SENSOR Click here

    OK

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

  2. INSPECT FRONT ROOM TEMPERATURE SENSOR


    1. A01ER2LE07

      Remove the front room temperature sensor Click here.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1 (+) - 2 (-) 10°C (50°F) 3.00 to 3.73 kΩ
      15°C (59°F) 2.45 to 2.88 kΩ
      20°C (68°F) 1.95 to 2.30 kΩ
      25°C (77°F) 1.60 to 1.80 kΩ
      30°C (86°F) 1.28 to 1.47 kΩ
      35°C (95°F) 1.00 to 1.22 kΩ
      40°C (104°F) 0.80 to 1.00 kΩ
      45°C (113°F) 0.65 to 0.85 kΩ
      50°C (122°F) 0.50 to 0.70 kΩ
      55°C (131°F) 0.44 to 0.60 kΩ
      60°C (140°F) 0.36 to 0.50 kΩ

      Note


      • Even slightly touching the sensor may change the resistance value. Be sure to hold the connector of the sensor.

      • When measuring, the sensor temperature must be the same as the ambient temperature.

      Tech Tips

      As the temperature increases, the resistance decreases (See the graph).


    NG

    REPLACE FRONT ROOM TEMPERATURE SENSOR Click here

    OK

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

    A01EP1QE01

    1. Disconnect the E32 sensor connector.

    2. Disconnect the E35 amplifier connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      E32-1 (+) - E35-9 (TR) Always Below 1 Ω
      E32-2 (-) - E35-32 (SG-1)
      E35-9 (TR) - Body ground Always 10 kΩ or higher
      E35-32 (SG-1) - Body ground

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here