AIR CONDITIONING SYSTEM(for Automatic Air Conditioning System), Diagnostic DTC:B1434/23, B1435/-23

DTC Code DTC Name
B1434/23 Open in Evaporator Sensor Circuit
B1435/-23 Short in Evaporator Sensor Circuit

DESCRIPTION

The evaporator temperature sensor (No. 1 cooler thermistor) is installed on the No. 1 cooler evaporator sub-assembly in the air conditioner unit to detect the temperature of the air that has passed through the No. 1 cooler evaporator sub-assembly and is used to control the air conditioning. It sends signals to the air conditioning control assembly. The resistance of the evaporator temperature sensor (No. 1 cooler thermistor) changes in accordance with the cooled air temperature that has passed through the No. 1 cooler evaporator sub-assembly. As the temperature decreases, the resistance increases. As the temperature increases, the resistance decreases.

The air conditioning control assembly applies voltage (5 V) to the evaporator temperature sensor (No. 1 cooler thermistor) and reads voltage changes as the resistance of the evaporator temperature sensor (No. 1 cooler thermistor) changes. This sensor is used for frost prevention.

DTC No. DTC Detection Condition Trouble Area
B1434/23 Open in evaporator sensor circuit

  • Evaporator temperature sensor (No. 1 cooler thermistor)

  • Harness or connector between evaporator temperature sensor (No. 1 cooler thermistor) and air conditioning control assembly

  • Air conditioning control assembly
B1435/-23 Short in evaporator sensor circuit

  • Evaporator temperature sensor (No. 1 cooler thermistor)

  • Harness or connector between evaporator temperature sensor (No. 1 cooler thermistor) and air conditioning control assembly

  • Air conditioning control assembly

WIRING DIAGRAM

A004J8SE03
*a EVAPORATOR TEMPERATURE SENSOR (NO. 1 COOLER THEMISTOR)
*b AIR CONDITIONING CONTROL ASSEMBLY

PROCEDURE


  1. READ VALUE USING GTS


    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.

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

      Evaporator Temp Sensor

      (Evap Temp)

      Evaporator temperature sensor (No. 1 cooler thermistor) /

      Min.: -82.48°C (-116.46°F)

      Max.: 153.55°C (308.39°F)

      		 Actual evaporator temperature displayed -
      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 EVAPORATOR TEMPERATURE SENSOR (NO. 1 COOLER THERMISTOR) Click here

    A

  2. CHECK FOR DTC


    1. Clear the DTCs Click here

    2. Check the DTCs Click here

      OK
      DTC is not output.

    OK

    END

    NG

    REPLACE AIR CONDITIONING CONTROL ASSEMBLY Click here

  3. INSPECT EVAPORATOR TEMPERATURE SENSOR (NO. 1 COOLER THERMISTOR)


    1. Remove the evaporator temperature sensor (No. 1 cooler thermistor) Click here.

    2. Inspect the evaporator temperature sensor (No. 1 cooler thermistor) Click here


    NG

    REPLACE EVAPORATOR TEMPERATURE SENSOR (NO. 1 COOLER THERMISTOR) Click here

    OK

  4. CHECK HARNESS AND CONNECTOR (EVAPORATOR TEMPERATURE SENSOR (NO. 1 COOLER THERMISTOR) - AIR CONDITIONING CONTROL ASSEMBLY)


    1. Disconnect the D20 air conditioning control assembly.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A25-1 - D20-17(TE) Always Below 1 Ω
      A25-2 - D20-6(SG) Always Below 1 Ω
      A25-1 - Body ground Always 10 kΩ or higher
      A25-2 - Body ground Always 10 kΩ or higher

    OK

    REPLACE AIR CONDITIONING CONTROL ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR