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DTC    B1413/13    Evaporator Temperature Sensor Circuit

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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 A/C amplifier. 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 A/C amplifier 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.

DTC No.
DTC Detection Condition
Trouble Area
B1413/13
Open or short in evaporator temperature sensor circuit
  1. Evaporator temperature sensor
  2. Air conditioning harness
  3. A/C amplifier

WIRING DIAGRAM


E161684E09


INSPECTION PROCEDURE

1.READ VALUE USING INTELLIGENT TESTER

  1. Connect the intelligent tester to the DLC3.

  1. Turn the power switch on (IG).

  1. Turn the intelligent tester on.

  1. Enter the following menus: Body / Air Conditioner / Data List.

  1. 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.



    E138242E50

  1. Disconnect the evaporator temperature sensor connector.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    z16-1 - z16-2
    		-10°C (14°F)
    		7.30 to 9.10 kΩ
    z16-1 - z16-2
    		-5°C (23°F)
    		5.65 to 6.95 kΩ
    z16-1 - z16-2
    		0°C (32°F)
    		4.40 to 5.35 kΩ
    z16-1 - z16-2
    		5°C (41°F)
    		3.40 to 4.15 kΩ
    z16-1 - z16-2
    		10°C (50°F)
    		2.70 to 3.25 kΩ
    z16-1 - z16-2
    		15°C (59°F)
    		2.14 to 2.58 kΩ
    z16-1 - z16-2
    		20°C (68°F)
    		1.71 to 2.05 kΩ
    z16-1 - z16-2
    		25°C (77°F)
    		1.38 to 1.64 kΩ
    z16-1 - z16-2
    		30°C (86°F)
    		1.11 to 1.32 kΩ

    NOTICE:
    1. Hold the sensor only by its connector. Touching the sensor may change the resistance value.
    2. When measuring, the sensor temperature must be the same as the ambient temperature.

    HINT:
    As the temperature increases, the resistance decreases (see the graph).

    Text in Illustration 
    *1
    		Component without harness connected
    (Evaporator Temperature Sensor)
    *2
    		Sensing Portion



NG
REPLACE EVAPORATOR TEMPERATURE SENSOR (Click here)
OK


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


    E161765E09

  1. Remove the air conditioning harness.



    E124472E30

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    z6-6 (TE) - z16-2
    		Always
    		Below 1 Ω
    z6-5 (SG) - z16-1
    		Always
    		Below 1 Ω
    z6-6 (TE) - Body ground
    		Always
    		10 kΩ or higher
    z6-5 (SG) - Body ground
    		Always
    		10 kΩ or higher

    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to A/C Amplifier)
    *2
    		Front view of wire harness connector
    (to Evaporator Temperature Sensor)



NG
REPLACE AIR CONDITIONING HARNESS (Click here)
OK

REPLACE A/C AMPLIFIER (Click here)