AIR CONDITIONING SYSTEM(for Automatic Air Conditioning System with Top-mounted Air Conditioner Pressure Sensor), Diagnostic DTC:B1411

DTC Code DTC Name
B1411 Room Temperature Sensor Circuit

DESCRIPTION

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

DTC No. Detection Item DTC Detection Condition Trouble Area Memory
B1411 Room Temperature Sensor Circuit

Any of the following conditions is met:


  • Open in cooler thermistor (room temperature sensor) circuit

  • Short in cooler thermistor (room temperature sensor) circuit

  • Cooler (room temp. sensor) thermistor

  • Harness or connector between cooler (room temp. sensor) thermistor and air conditioning amplifier assembly

  • Air conditioning amplifier assembly

Memorized

(4 seconds or more)*

Tech Tips

If the cabin temperature is approximately -56.0°C (-68.8°F) or lower, DTC B1411 may be output even though the system is normal.

DTC Detection Conditions
Vehicle Condition
Pattern 1 Pattern 2
Diagnosis Condition Ignition switch ON ○ ○
Malfunction Status Open in cooler thermistor (room temperature sensor) circuit ○ -
Short in cooler thermistor (room temperature sensor) circuit - ○
Detection Time 4 seconds or more 4 seconds or more
Number of Trips 1 trip 1 trip

Tech Tips

DTC will be output when conditions for either of the patterns in the table above are met.

WIRING DIAGRAM

A001V1LE01
*a Cooler (Room Temp. Sensor) Thermistor
*b Air Conditioning Amplifier Assembly

PROCEDURE


  1. READ VALUE USING GTS (ROOM TEMPERATURE SENSOR)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch ON.

    3. Turn the GTS on.

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

    5. Read the Data List according to the display on the GTS.


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

      Min.: -6.50°C (20.30°F)

      Max.: 57.25°C (135.05°F)

      		 Actual cabin temperature displayed -

      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
      NG A
      OK (When troubleshooting according to Problem Symptoms Table) B
      OK (When troubleshooting according to the DTC) C

    B

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

    C

    CHECK FOR DTC Click here

    A

  2. INSPECT COOLER (ROOM TEMP. SENSOR) THERMISTOR


    1. Remove the cooler (room temp. sensor) thermistor.

      Click here

    2. Inspect the cooler (room temp. sensor) thermistor.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE COOLER (ROOM TEMP. SENSOR) THERMISTOR Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (COOLER (ROOM TEMP. SENSOR) THERMISTOR - AIR CONDITIONING AMPLIFIER ASSEMBLY)


    1. Disconnect the F72 air conditioning amplifier assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F72-30 (TR) - F60-1 Always Below 1 Ω
      F72-31 (SG-1) - F60-2 Always Below 1 Ω
      F72-30 (TR) or F60-1 - Body ground Always 10 kΩ or higher
      F72-31 (SG-1) or F60-2 - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  4. CHECK FOR DTC


    1. Clear the DTCs.

      Click here


      Body Electrical > Air Conditioner > Clear DTCs

    2. Check for DTCs.

      Click here


      Body Electrical > Air Conditioner > Trouble Codes
      Result
      Result Proceed to
      DTCs are not output A
      DTCs are output B

    A

    USE SIMULATION METHOD TO CHECK Click here

    B

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here