AIR CONDITIONING SYSTEM, Diagnostic DTC:B1413

DTC Code DTC Name
B1413 Evaporator Temperature Circuit or Evaporator Fin Thermistor

DESCRIPTION

The No. 1 cooler thermistor is installed to the evaporator in the air conditioner unit to detect the temperature of the cooled air that has passed through the evaporator, which is used to control the air conditioning system. It sends signals to the air conditioning amplifier assembly. The resistance of the No. 1 cooler thermistor changes in accordance with the temperature of the cooled air that has passed through the evaporator. 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 No. 1 cooler thermistor and reads voltage changes as the resistance of the No. 1 cooler thermistor changes. This sensor is used for frost prevention.

DTC No. Detection Item DTC Detection Condition Trouble Area Memory
B1413 Evaporator Temperature Sensor Circuit

  • Diagnosis condition: None

  • Malfunction status: Open or short in evaporator temperature sensor circuit

  • Detection time: None (Present malfunction), continuously for 4 seconds or more (Past malfunction)

  • No. 1 cooler thermistor

  • Air conditioning harness assembly

  • Air conditioning amplifier assembly

 Memorized

WIRING DIAGRAM

B000T19E29
*a Air Conditioning Harness Assembly
*b No. 1 Cooler Thermistor
*c Air Conditioning Amplifier Assembly

PROCEDURE


  1. READ VALUE USING GTS (EVAPORATOR FIN THERMISTOR)


    1. Connect the GTS to the DLC3.

    2. Turn the power switch on (IG).

    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
      Evaporator Fin Thermistor No. 1 cooler thermistor

      Min.: -29.70°C (-21.46°F)

      Max.: 59.55°C (139.19°F)

      		 Actual evaporator temperature displayed

      No. 1 ooler thermistor system malfunction


      • When open circuit: -29.70°C (-21.46°F)

      • When short circuit: 59.55°C (139.19°F)

      Body Electrical > Air Conditioner > Data List
      Tester Display
      Evaporator Fin Thermistor
      OK
      The display is as specified in the normal condition column.
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    NG

  2. INSPECT NO. 1 COOLER THERMISTOR


    1. Remove the No. 1 cooler thermistor.

      Click here

    2. Inspect the No. 1 cooler thermistor.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE NO. 1 COOLER THERMISTOR Click here

    OK

  3. CHECK AIR CONDITIONING HARNESS ASSEMBLY


    1. Remove the air conditioning harness assembly.

      Click here

      B000OVKC02
      *1 Air Conditioning Harness Assembly - -
      *a to No. 1 Cooler Thermistor Connector *b to Air Conditioning Amplifier Assembly Connector
      *c

      Front view of air conditioning harness assembly

      (to No. 1 Cooler Thermistor)

      		 *d

      Front view of air conditioning harness assembly

      (to Air Conditioning Amplifier Assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      z1-6 (TEA) - 2 Always Below 1 Ω
      z1-5 (SGA) - 1 Always Below 1 Ω
      z1-6 (TEA) or 2 - Other terminals and body ground Always 10 kΩ or higher
      z1-5 (SGA) or 1 - Other terminals and body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    NG

    REPLACE AIR CONDITIONING HARNESS ASSEMBLY Click here