Dtc 21 Solar Sensor Circuit


DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK AIR CONDITIONING AMPLIFIER ASSEMBLY

CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - SOLAR SENSOR)

REPLACE COOLER THERMISTOR (SOLAR SENSOR)

DTC 21 Solar Sensor Circuit


DESCRIPTION

Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.Air Conditioning.Air Conditioning System (For Automatic Air Conditioning System). Dtc 21 Solar Sensor Circuit
The cooler thermistor (solar sensor), which is installed on the upper side of the instrument panel, detects sunlight and controls the air conditioning in AUTO mode. The output current from the cooler thermistor (solar sensor) varies according to the amount of sunlight. When the amount of sunlight increases, the output current increases. As the amount of sunlight decreases, the output current decreases. The air conditioning amplifier assembly detects the output current from the cooler thermistor (solar sensor).

DTC Code
Detection Item
Trouble Area
21
An open in cooler thermistor (solar sensor) circuit
(If check is performed in a dark place, DTC 21 may be stored)
  1. Cooler thermistor (solar 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 21 Solar Sensor Circuit


INSPECTION PROCEDURE

HINT:
If the check is performed in a dark place, DTC 21 may be stored even though the system is normal.
1.CHECK AIR CONDITIONING AMPLIFIER ASSEMBLY


    Toyota Fortuner. Ggn50, 60 Kun51, 61 Tgn51 Lan50.Air Conditioning.Air Conditioning System (For Automatic Air Conditioning System). Dtc 21 Solar Sensor Circuit

  1. Remove the air conditioning amplifier assembly with its connectors still connected (Toyota Fortuner RM000001K3A018X.html).

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

    Standard Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    A37-2 (S5-3) - A37-7 (TS)
    1. Ignition switch ON
    2. Solar sensor subjected to electric light
    3. Vehicle indoors
    		0.8 to 4.3 V
    1. Ignition switch ON
    2. Solar sensor covered with a cloth
    3. Vehicle indoors
    		Below 0.8 V
    Text in Illustration
    *a
    		Component with harness connected
    (Air Conditioning Amplifier Assembly)
    HINT:
    1. As the inspection light is moved away from the sensor, the voltage decreases.
    2. Use an incandescent light for inspection. Bring it within 30 cm (11.8 in.) of the sensor.
    Result
    Result
    		Proceed to
    OK (When troubleshooting according to problem symptoms table.)
    		A
    OK (When troubleshooting according to DTC.)
    		B
    NG
    		C


B
REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY (Toyota Fortuner RM000001K3A018X.html)

C
Go to step 2
A

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE (Toyota Fortuner RM0000045E300YX.html)

2.CHECK HARNESS AND CONNECTOR (AIR CONDITIONING AMPLIFIER - SOLAR SENSOR)

  1. Disconnect the A37 air conditioning amplifier assembly connector.

  1. Disconnect the A18 cooler thermistor (solar sensor) connector.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    A37-2 (S5-3) - A18-1
    		Always
    		Below 1 Ω
    A37-7 (TS) - A18-2
    A37-2 (S5-3) - Body ground
    		Always
    		10 kΩ or higher
    A37-7 (TS) - Body ground


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


3.REPLACE COOLER THERMISTOR (SOLAR SENSOR)

  1. Temporally replace the cooler thermistor (solar sensor) with a new or normally functioning one (Toyota Fortuner RM000003S0L001X.html).

  1. Clear the DTCs (Toyota Fortuner RM000002LIT02IX.html).

  1. Check the DTCs (Toyota Fortuner RM000002LIT02IX.html).

    OK:
    DTC code 21 is not output.


NG
REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY (Toyota Fortuner RM000001K3A018X.html)
OK

END (COOLER THERMISTOR [SOLAR SENSOR] IS DEFECTIVE) (Toyota Fortuner RM000003S0L001X.html)