Dtc 11 Room Temperature Sensor Circuit


DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

INSPECT COOLER THERMISTOR (A/C ROOM TEMPERATURE SENSOR)

CHECK AIR CONDITIONING AMPLIFIER ASSEMBLY (TR VOLTAGE)

CHECK HARNESS AND CONNECTOR (COOLER THERMISTOR - AIR CONDITIONING AMPLIFIER)

DTC 11 Room Temperature Sensor Circuit


DESCRIPTION

The cooler thermistor (A/C room temperature sensor) is installed in the instrument panel to detect the room temperature and control the heater and air conditioning AUTO function. The resistance of the cooler thermistor changes in accordance with the room temperature. As the temperature decreases, the resistance increases. As the temperature increases, the resistance decreases.
The air conditioning amplifier applies voltage (5 V) to the cooler thermistor and reads voltage changes as the resistance of the cooler thermistor changes.

DTC Code
Detection Item
Trouble Area
11
Open or short in room temperature sensor circuit
  1. Cooler thermistor (A/C room temperature sensor)
  2. Harness or connector
  3. Air conditioning amplifier assembly

WIRING DIAGRAM


Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.Air Conditioning.Air Conditioning System (For Automatic Air Conditioning System). Dtc 11 Room Temperature Sensor Circuit


INSPECTION PROCEDURE

1.INSPECT COOLER THERMISTOR (A/C ROOM TEMPERATURE SENSOR)


    Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.Air Conditioning.Air Conditioning System (For Automatic Air Conditioning System). Dtc 11 Room Temperature Sensor Circuit

  1. Remove the cooler thermistor.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    1 - 2
    		10°C (50°F)
    		3.00 to 3.73 kΩ
    15°C (59°F)
    		2.45 to 2.88 kΩ
    20°C (68°F)
    		1.95 to 2.30 kΩ
    25°C (77°F)
    		1.60 to 1.80 kΩ
    30°C (86°F)
    		1.28 to 1.47 kΩ
    35°C (95°F)
    		1.00 to 1.22 kΩ
    40°C (104°F)
    		0.80 to 1.00 kΩ
    45°C (113°F)
    		0.65 to 0.85 kΩ
    50°C (122°F)
    		0.50 to 0.70 kΩ
    55°C (131°F)
    		0.44 to 0.60 kΩ
    60°C (140°F)
    		0.36 to 0.50 kΩ
    NOTICE:
    1. Even slightly touching the thermistor may change the resistance value. Be sure to hold the connector of the thermistor.
    2. When measuring the resistance, the thermistor temperature must be the same as the ambient temperature.
    HINT:
    As the temperature increases, the resistance decreases (Refer to the graph).


NG
REPLACE COOLER THERMISTOR (A/C ROOM TEMPERATURE SENSOR) (Toyota Fortuner RM000003S0H000X.html)
OK


2.CHECK AIR CONDITIONING AMPLIFIER ASSEMBLY (TR VOLTAGE)


    Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.Air Conditioning.Air Conditioning System (For Automatic Air Conditioning System). Dtc 11 Room Temperature Sensor Circuit

  1. Remove the air conditioning amplifier with its connectors still connected.

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

    Standard Voltage:
    Tester Connection
    		Switch Condition
    		Specified Condition
    A15-18 (TR) - A15-13 (SG-3)
    		Ignition switch ON
    Cabin temperature: 25°C (77°F)
    		1.8 to 2.2 V
    Ignition switch ON
    Cabin temperature: 40°C (104°F)
    		1.2 to 1.6 V
    HINT:
    As the temperature increases, the voltage decreases.
    Result
    Result
    		Proceed to
    OK (Checking from the PROBLEM SYMPTOMS TABLE)
    		A
    OK (Checking from the DTC)
    		B
    NG
    		C


B
REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY (Toyota Fortuner RM0000012KH002X.html)

C
Go to step 3
A

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE (Toyota Fortuner RM000003S6F000X.html)

3.CHECK HARNESS AND CONNECTOR (COOLER THERMISTOR - AIR CONDITIONING AMPLIFIER)


    Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.Air Conditioning.Air Conditioning System (For Automatic Air Conditioning System). Dtc 11 Room Temperature Sensor Circuit

  1. Disconnect the A17 thermistor connector.

  1. Disconnect the A15 amplifier connector.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    A15-18 (TR) - A17-2
    		Always
    		Below 1 Ω
    A15-13 (SG-3) - A17-1
    A15-18 (TR) - Body ground
    		Always
    		10 kΩ or higher
    A15-13 (SG-3) - Body ground


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY (Toyota Fortuner RM0000012KH002X.html)