AIR CONDITIONING SYSTEM, Diagnostic DTC:B1411/11

DTC Code DTC Name
B1411/11 Room Temperature Sensor Circuit

DESCRIPTION

The room temperature sensor is installed in the instrument panel to detect the cabin temperature and control the heater and air conditioning AUTO mode. The resistance of the room temperature sensor changes in accordance with the cabin temperature. As the temperature decreases, the resistance increases. As the temperature increases, the resistance decreases.

The air conditioning amplifier applies a voltage (5 V) to the room temperature sensor and reads voltage changes as changes in the resistance of the room temperature sensor.

DTC No. DTC Detection Condition Trouble Area
B1411/11 Open or short in room temperature sensor circuit
  • Room temperature sensor

  • Harness or connector between room temperature sensor and A/C amplifier

  • A/C amplifier

WIRING DIAGRAM

A0163CBE08

INSPECTION PROCEDURE

PROCEDURE


  1. READ VALUE USING INTELLIGENT TESTER


    1. Connect the intelligent tester to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the intelligent tester on.

    4. Select the item below in the Data List, and read the display on the intelligent tester.

      Data List / Air Conditioner
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note

      Room Temperature Sensor

      (Room Temp)

      Room temperature sensor / min.: -6.5°C (20.3°F), max.: 57.25°C (135.05°F) Actual cabin temperature is displayed -
      OK
      The display is as specified in the normal condition column.
      Result
      Result Proceed to
      NG A
      OK (When troubleshooting according to the Problem Symptoms Table) B
      OK (When troubleshooting according to the DTC) C

    B
    C
    A
  2. INSPECT ROOM TEMPERATURE SENSOR


    1. Remove the room temperature sensor.

    2. A015ZMEE05

      Disconnect the room temperature sensor connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      J38-1 - J38-2 10°C (50°F) 3.00 to 3.73 kΩ
      J38-1 - J38-2 15°C (59°F) 2.45 to 2.88 kΩ
      J38-1 - J38-2 20°C (68°F) 1.95 to 2.30 kΩ
      J38-1 - J38-2 25°C (77°F) 1.60 to 1.80 kΩ
      J38-1 - J38-2 30°C (86°F) 1.28 to 1.47 kΩ
      J38-1 - J38-2 35°C (95°F) 1.00 to 1.22 kΩ
      J38-1 - J38-2 40°C (104°F) 0.80 to 1.00 kΩ
      J38-1 - J38-2 45°C (113°F) 0.65 to 0.85 kΩ
      J38-1 - J38-2 50°C (122°F) 0.50 to 0.70 kΩ
      J38-1 - J38-2 55°C (131°F) 0.44 to 0.60 kΩ
      J38-1 - J38-2 60°C (140°F) 0.36 to 0.50 kΩ

      Note


      • Hold the sensor only by its connector. Touching the sensor may change the resistance value.

      • 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
    OK
  3. CHECK HARNESS AND CONNECTOR (ROOM TEMPERATURE SENSOR - A/C AMPLIFIER)


    1. A0162IGE01

      Disconnect the A/C amplifier connector.

    2. A01614UE19

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      J58-16 (TR) - J38-1 Always Below 1 Ω
      J58-19 (SG-1) - J38-2 Always Below 1 Ω
      J58-16 (TR) - Body ground Always 10 kΩ or higher
      J58-19 (SG-1) - Body ground Always 10 kΩ or higher

    NG
    OK