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DTC    B14A8    Glass Temperature Sensor Circuit

for Preparation Click here


DESCRIPTION

The air conditioning amplifier assembly detects the windshield glass surface temperature from this circuit. The air conditioning amplifier assembly applies voltage to the air conditioning thermistor assembly (glass temperature sensor). As the windshield glass surface temperature rises, the resistance decreases. The air conditioning amplifier assembly detects the resistance change as the windshield glass surface temperature changes.

DTC No.
DTC Detection Condition
Trouble Area
B14A8
Open or short in glass temperature sensor circuit
  1. Wire harness or connector
  2. Air conditioning thermistor assembly (glass temperature sensor)
  3. Air conditioning amplifier assembly

HINT:
The whole air conditioning thermistor assembly should be replaced if the glass temperature sensor is malfunctioning.


WIRING DIAGRAM


E222434E04


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
    Glass Temperature
    		Glass temperature/
    Min.: -327.68°C (-557.82°F)
    Max.: 327.67°C (621.81°F)
    		Actual glass 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 AIR CONDITIONING THERMISTOR ASSEMBLY (GLASS TEMPERATURE SENSOR)


    E208908E06

  1. Remove the air conditioning thermistor assembly (glass temperature sensor) (Click here).

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    T11-1 (SEG3) - T11-4 (TFG)
    		10°C (50°F)
    		5.92 to 6.09 kΩ
    T11-1 (SEG3) - T11-4 (TFG)
    		15°C (59°F)
    		4.94 to 5.07 kΩ
    T11-1 (SEG3) - T11-4 (TFG)
    		20°C (68°F)
    		4.20 to 4.29 kΩ
    T11-1 (SEG3) - T11-4 (TFG)
    		25°C (77°F)
    		3.64 to 3.70 kΩ
    T11-1 (SEG3) - T11-4 (TFG)
    		30°C (86°F)
    		3.19 to 3.26 kΩ
    T11-1 (SEG3) - T11-4 (TFG)
    		35°C (95°F)
    		2.85 to 2.91 kΩ
    T11-1 (SEG3) - T11-4 (TFG)
    		40°C (104°F)
    		2.58 to 2.64 kΩ
    T11-1 (SEG3) - T11-4 (TFG)
    		45°C (113°F)
    		2.37 to 2.43 kΩ
    T11-1 (SEG3) - T11-4 (TFG)
    		50°C (122°F)
    		2.21 to 2.26 kΩ
    T11-1 (SEG3) - T11-4 (TFG)
    		55°C (131°F)
    		2.07 to 2.12 kΩ
    T11-1 (SEG3) - T11-4 (TFG)
    		60°C (140°F)
    		1.97 to 2.01 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.

    Text in Illustration 
    *a
    		Heat Conduction Sheet Part
    *b
    		Component without harness connected
    (Air Conditioning Thermistor Assembly (Glass Temperature Sensor))
    *c
    		Resistance (kΩ)
    *d
    		Temperature (°C (°F))



NG
REPLACE AIR CONDITIONING THERMISTOR ASSEMBLY (Click here)
OK


3.CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - GLASS TEMPERATURE SENSOR)

  1. Disconnect the T11 air conditioning thermistor assembly (glass temperature sensor) connector.

  1. Disconnect the H86 air conditioning amplifier assembly connector.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    T11-4 (TFG) - H86-15 (TFG)
    		Always
    		Below 1 Ω
    T11-4 (TFG) - Body ground
    		Always
    		10 kΩ or higher
    T11-1 (SEG3) - H86-7 (LBLO)
    		Always
    		Below 1 Ω
    T11-1 (SEG3) - Body ground
    		Always
    		10 kΩ or higher



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY (Click here)