AIR CONDITIONING SYSTEM, Diagnostic DTC:B1413/13

DTC Code DTC Name
B1413/13 Evaporator Temperature Sensor Circuit

DESCRIPTION

The No. 1 cooler thermistor (evaporator temperature sensor) is installed on the evaporator in the air conditioner unit to detect the cooled air temperature that has passed through the evaporator and control the air conditioning. It sends appropriate signals to the air conditioning amplifier. The resistance of the No. 1 cooler thermistor (evaporator temperature sensor) 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 air conditioning amplifier applies voltage (5 V) to the No. 1 cooler thermistor (evaporator temperature sensor) and reads voltage changes as the resistance of the No. 1 cooler thermistor (evaporator temperature sensor) changes. This sensor is used for frost prevention.

DTC Code DTC Detection Condition Trouble Area
B1413/13 Open or short in evaporator temperature sensor circuit

  • No. 1 cooler thermistor (evaporator temperature sensor)

  • Air conditioning harness (evaporator temperature sensor)

  • Air conditioning amplifier

WIRING DIAGRAM

A000WBYE55
*1 Evaporator Temperature Sensor
*2 Air Conditioning Harness
*3 Air Conditioning Amplifier

PROCEDURE


  1. READ VALUE USING INTELLIGENT TESTER (EVAPORATOR FIN THERMISTOR)


    1. Use the Data List to check if the evaporator fin thermistor is functioning properly.

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

      Evaporator fin thermistor /

      Min.: -29.7°C (-21.46°F)

      Max.: 59.55°C (139.19°F)

      		 Actual evaporator temperature is displayed

      Open in circuit: -29.7°C (-21.46°F)

      Short in circuit: 59.55°C (139.19°F)
      OK
      The display is as specified in the normal condition.

    OK

    REPLACE AIR CONDITIONING AMPLIFIER Click here

    NG

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

    A000V00E01

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

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

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

      Note


      • Even slightly touching the sensor may change the resistance value. Be sure to hold the connector of the sensor.

      • 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).


    OK

    REPLACE AIR CONDITIONING HARNESS Click here

    NG

    REPLACE NO. 1 COOLER THERMISTOR Click here