AIR CONDITIONING SYSTEM, Diagnostic DTC:B1413/13

DTC Code DTC Name
B1413/13 Evaporator Temperature Sensor Circuit

DESCRIPTION

The evaporator temperature sensor (A/C thermistor) is installed on the evaporator in the air conditioning unit to detect the cooled air temperature that has passed through the evaporator and to control the air conditioning. It sends appropriate signals to the A/C amplifier. The resistance of the evaporator temperature sensor (A/C thermistor) changes in accordance with the cooled air temperature that has passed through the evaporator. As the temperature decreases, the resistance increases. As the temperature increases, the resistance decreases.

The A/C amplifier applies voltage (5 V) to the evaporator temperature sensor (A/C thermistor) and reads voltage changes as the resistance of the evaporator temperature sensor (A/C thermistor) changes. This sensor is used for frost prevention.

DTC No. DTC Detection Condition Trouble Area
B1413/13 Open or short in evaporator temperature sensor circuit

  • Evaporator temperature sensor

  • Air conditioning harness

  • A/C amplifier

WIRING DIAGRAM

A01CB7LE03

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. Enter the following menus: Body / 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 Fin Thermistor

      Evaporator temperature sensor /

      Min.: -29.7°C (-21.46°F)

      Max.: 59.55°C (139.19°F)

      		 Actual evaporator temperature displayed -
      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

    REPLACE A/C AMPLIFIER Click here

    A

  2. INSPECT EVAPORATOR TEMPERATURE SENSOR


    1. Remove the evaporator temperature sensor.

    2. A01CDABE39

      Disconnect the evaporator temperature sensor connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      e2-1 - e2-2 -10°C (14°F) 7.30 to 9.10 kΩ
      e2-1 - e2-2 -5°C (23°F) 5.65 to 6.95 kΩ
      e2-1 - e2-2 0°C (32°F) 4.40 to 5.35 kΩ
      e2-1 - e2-2 5°C (41°F) 3.40 to 4.15 kΩ
      e2-1 - e2-2 10°C (50°F) 2.70 to 3.25 kΩ
      e2-1 - e2-2 15°C (59°F) 2.14 to 2.58 kΩ
      e2-1 - e2-2 20°C (68°F) 1.71 to 2.05 kΩ
      e2-1 - e2-2 25°C (77°F) 1.38 to 1.64 kΩ
      e2-1 - e2-2 30°C (86°F) 1.11 to 1.32 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

    REPLACE EVAPORATOR TEMPERATURE SENSOR Click here

    OK

  3. INSPECT AIR CONDITIONING HARNESS (A/C AMPLIFIER - EVAPORATOR TEMPERATURE SENSOR)


    1. A01CE4WE03

      Remove the air conditioning harness.

    2. A01CAJPE16

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      z12-6 (TE) - e2-2 Always Below 1 Ω
      z12-5 (SG) - e2-1 Always Below 1 Ω
      z12-6 (TE) - Body ground Always 10 kΩ or higher
      z12-5 (SG) - Body ground Always 10 kΩ or higher

    NG

    REPLACE AIR CONDITIONING HARNESS Click here

    OK

    REPLACE A/C AMPLIFIER Click here