AIR CONDITIONING SYSTEM (for Automatic Air Conditioning System), Diagnostic DTC:B1421/21

DTC Code DTC Name
B1421/21 Solar Sensor Circuit (Passenger Side)

DESCRIPTION

A017C4BE01

The solar sensor, which is installed on the upper side of the instrument panel, detects sunlight and controls the air conditioning AUTO mode. The output voltage from the solar sensor varies in accordance with the amount of sunlight. When the sunlight increases, the output voltage increases. As the sunlight decreases, the output voltage decreases. The air conditioning amplifier detects changes in the output voltage from the solar sensor.

DTC No. DTC Detection Condition Trouble Area
B1421/21 Open or short in passenger side solar sensor circuit

  • Solar sensor

  • Wire harness between solar sensor and air conditioning amplifier

  • Wire harness between solar sensor and main body ECU

  • Air conditioning amplifier

WIRING DIAGRAM

A017BFAE18

INSPECTION PROCEDURE

PROCEDURE


  1. READ VALUE USING INTELLIGENT TESTER (SOLAR SENS-P)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch on (IG) and turn the intelligent tester main switch on.

    3. Select the item below in the Data List, and read the value displayed on the intelligent tester.

      Data List / Air Conditioner:
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Solar Sens-P

      Passenger side solar sensor /

      Min.: 0, Max.: 255

      		 Passenger side solar sensor value increases as brightness increases -
      OK
      The display is as specified in the normal condition column.
      Result
      Result Proceed to
      NG A
      OK (Checking from PROBLEM SYMPTOMS TABLE) B
      OK (Checking from DTC) C

    B

    PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE Click here

    C

    REPLACE AIR CONDITIONING AMPLIFIER Click here

    A

  2. CHECK SOLAR SENSOR (SENSOR POWER INPUT)


    1. A017D4QE02

      Disconnect the F1 solar sensor connector.

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

      Standard voltage
      Tester Connection Condition Specified Condition
      F1-6 (CLTB) - F1-3 (CLTE) Ignition switch off Below 1 V
      F1-6 (CLTB) - F1-3 (CLTE) Ignition switch on (IG) 11 to 14 V

    OK

    CHECK SOLAR SENSOR Click here

    NG

  3. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - SOLAR SENSOR)


    1. A017DHDE04

      Disconnect the D6 main body ECU connector.

    2. Disconnect the F1 solar sensor connector.

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

      Standard resistance
      Tester Connection Condition Specified Condition
      D6-20 (CLTB) - F1-6 (CLTB) Always Below 1 Ω
      D6-18 (CLTE) - F1-3 (CLTE) Always Below 1 Ω
      D6-20 (CLTB) - Body ground Always 10 kΩ or higher
      D6-18 (CLTE) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE MAIN BODY ECU (INSTRUMENT PANEL JUNCTION BLOCK)

  4. CHECK SOLAR SENSOR


    1. A017C2JE55

      Remove the solar sensor Click here with its connector still connected.

    2. Connect the battery's positive (+) lead to terminal 6 (CLTB) and the negative (-) lead to terminal 3 (CLTE) of the solar sensor.

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

      Standard voltage
      Tester Connection Condition Specified Condition
      F1-2 (TSR) - F1-3 (CLTE)*1 Sensor is subjected to electric light 0.8 to 4.3 V
      F1-2 (TSR) - F1-3 (CLTE)*1 Sensor is covered with a cloth Below 0.8 V
      F1-1 (TSL) - F1-3 (CLTE)*2 Sensor is subjected to electric light 0.8 to 4.3 V
      F1-1 (TSL) - F1-3 (CLTE)*2 Sensor is covered with a cloth Below 0.8 V

      • *1: for LHD

      • *2: for RHD

      Note


      • The connection procedure for using a digital tester such as a TOYOTA electrical tester is shown above. When using an analog tester, connect the negative (-) lead to terminal 6 and positive (+) lead to terminal 3 of the solar sensor.

      • While using the battery during inspection, do not bring the positive and negative tester probes too close to each other as a short circuit may occur.

      Tech Tips


      • Use an incandescent light for inspection. Bring it within about 30 cm (11.8 in.) of the solar sensor.

      • As the inspection light is moved away from the sensor, the voltage decreases.


    NG

    REPLACE SOLAR SENSOR Click here

    OK

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


    1. A017GB1E15

      Disconnect the F1 solar sensor connector.

    2. Disconnect the D33 air conditioning amplifier connector.

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

      Standard resistance
      Tester Connection Condition Specified Condition
      D33-32 (TSP) - F1-2 (TSR)*1 Always Below 1 Ω
      D33-32 (TSP) - F1-1 (TSL)*2 Always Below 1 Ω
      D33-32 (TSP) - Body ground Always 10 kΩ or higher

      • *1: for LHD

      • *2: for RHD


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE AIR CONDITIONING AMPLIFIER Click here