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) is installed in the instrument panel to detect the cabin temperature which is used to control the heater and air conditioning system AUTO mode. The resistance of the cooler thermistor (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 assembly applies a voltage (5 V) to the cooler thermistor (room temperature sensor) and reads voltage changes due to changes in the resistance of the cooler thermistor (room temperature sensor).

DTC No. Detection Item DTC Detection Condition Trouble Area Memory Note
B1411/11 Room Temperature Sensor Circuit Open or short in cooler thermistor (room temperature sensor) circuit
  • Cooler thermistor (room temperature sensor)

  • Harness or connector

  • Air conditioning amplifier assembly

Memorized (4 seconds or more) -

Tech Tips


  • The air conditioning amplifier assembly stores the DTC of the respective malfunction if it has occurred for the period of time indicated in the parentheses.

  • If the cabin temperature is approximately -18.6°C (-1.48°F) or less, DTC B1411/11 may be output even though the system is normal.

WIRING DIAGRAM

B0024KJE23
*a Cooler Thermistor (Room Temperature Sensor)
*b Air Conditioning Amplifier Assembly

CAUTION / NOTICE / HINT

Note

When the servo motor or air conditioning amplifier assembly is replaced, be sure to perform servo motor initialization.

Click here

PROCEDURE


  1. READ VALUE USING GTS (ROOM 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 / Air Conditioner / Data List.

    5. Check the value(s) by referring to the table below.


      Body Electrical > Air Conditioner > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      Room Temperature Sensor Cooler thermistor (room temperature sensor)

      Min.: -6.50°C (-20.30°F)

      Max.: 57.25°C (135.05°F)

      Actual cabin temperature displayed

      Cooler thermistor (room temperature sensor) system malfunction:


      • When open circuit: -6.50°C (-20.30°F)

      • When short circuit: 57.25°C (135.05°F)


      Body Electrical > Air Conditioner > Data List
      Tester Display
      Room Temperature Sensor
      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

    A
    B
    C
  2. 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

      Result
      Proceed to
      OK
      NG

    NG
    OK
  3. CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER ASSEMBLY - COOLER THERMISTOR [ROOM TEMPERATURE SENSOR])


    1. Disconnect the G33 air conditioning amplifier assembly connector.

    2. Disconnect the G26 cooler thermistor (room temperature sensor) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G33-29 (TR) - G26-2 (ST+) Always Below 1 Ω
      G33-34 (SG-2) - G26-1 (ST-) Always Below 1 Ω
      G26-1 (ST-) - G26-2 (ST+) Always 10 kΩ or higher
      G33-29 (TR) or G26-2 (ST+) - Body ground Always 10 kΩ or higher
      G33-34 (SG-2) or G26-1 (ST-) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK
    NG