AIR CONDITIONING SYSTEM, Diagnostic DTC:B1413/13

DESCRIPTION

The evaporator temperature sensor 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 air conditioning amplifier assembly. The resistance of the 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 assembly applies voltage (5 V) to the evaporator temperature sensor and reads voltage changes as the resistance of the evaporator temperature sensor changes. This sensor is used for frost prevention.

WIRING DIAGRAM

*a	Air Conditioning Harness Assembly
*b	Evaporator Temperature Sensor
*c	Air Conditioning Amplifier Assembly

PROCEDURE

1. READ VALUE USING INTELLIGENT TESTER

   
   

   1. Connect the intelligent tester to the DLC3.

   2. Turn the power 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 AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

   A

2. INSPECT EVAPORATOR TEMPERATURE SENSOR

   
   

   1. Remove the evaporator temperature sensor.

   2. Disconnect the e2 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).

      Text in Illustration

      *a	Component without harness connected (Evaporator Temperature Sensor)
      *b	Sensing Portion
      *c	Resistance (kΩ)
      *d	Allowable Range
      *e	Temperature (°C (°F))

   
   

   NG

   REPLACE EVAPORATOR TEMPERATURE SENSOR Click here

   OK

3. INSPECT AIR CONDITIONING HARNESS ASSEMBLY (AIR CONDITIONING AMPLIFIER - EVAPORATOR TEMPERATURE SENSOR)

   
   

   1. Remove the air conditioning harness assembly Click here.

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

      Standard Resistance
      Tester Connection Condition Specified Condition z1-6 (TEA) - e2-2 Always Below 1 Ω z1-5 (SGA) - e2-1 Always Below 1 Ω z1-6 (TEA) - Body ground Always 10 kΩ or higher z1-5 (SGA) - Body ground Always 10 kΩ or higher

   
   

   OK

   REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

   NG

   REPLACE AIR CONDITIONING HARNESS ASSEMBLY Click here