AIR CONDITIONING SYSTEM, Diagnostic DTC:B1413/13

DESCRIPTION

The No. 1 cooler thermistor is installed on 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.

• *1: The air conditioning amplifier assembly stores this DTC if the malfunction has occurred for the period of time indicated in the brackets.

WIRING DIAGRAM

PROCEDURE

1. READ VALUE USING GTS

   
   

   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. Check the value(s) by referring to the table below.

      
      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	-

      
      Body Electrical > Air Conditioner > Data List

      Tester Display
      Evaporator Fin Thermistor

      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 AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

   A

2. INSPECT NO. 1 COOLER THERMISTOR

   
   

   1. Remove the No. 1 cooler thermistor.

      Click here

      

      *a	Component without harness connected (No. 1 Cooler Thermistor)	*b	Sensing Portion
      *c	Resistance (kΩ)	*d	Temperature (°C (°F))
      *e	Allowable Range	-	-

   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

      
      

      • Hold the sensor only by its connector. Touching the sensing portion 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).

      Result
      Proceed to OK NG

   
   

   NG

   REPLACE NO. 1 COOLER THERMISTOR Click here

   OK

3. INSPECT AIR CONDITIONING HARNESS ASSEMBLY

   
   
   1. 

      *a	Front view of wire harness connector (to Air Conditioning Amplifier Assembly)

      Remove the air conditioning harness assembly.

      Click here

   2. 

      *a	Front view of wire harness connector (to No. 1 Cooler Thermistor)

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

      Standard Resistance
      Tester Connection Condition Specified Condition z1-11 (TEA) - 1 Always Below 1 Ω z1-12 (SGA) - 2 Always Below 1 Ω

      Result
      Proceed to OK NG

   
   

   OK

   REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

   NG

   REPLACE AIR CONDITIONING HARNESS ASSEMBLY Click here