LIGHTING SYSTEM, Diagnostic DTC:B1244

DTC Code DTC Name
B1244 Light Sensor Circuit Malfunction

DESCRIPTION

This DTC is output when a failure of the automatic light control sensor circuit is detected.

DTC No. DTC Detection Condition Trouble Area
B1244

  • Malfunction of automatic light control sensor

  • Open or short in automatic light control sensor circuit

  • Automatic light control sensor

  • Wire harness or connector

  • Main body ECU RH (Cowl side junction block RH)

WIRING DIAGRAM

A015ZF2E14

INSPECTION PROCEDURE

PROCEDURE


  1. READ VALUE USING INTELLIGENT TESTER


    1. Connect the intelligent tester to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the intelligent tester on.

    4. Enter the following menus: Body / Body / Data List.

    5. Read the display on the intelligent tester.

      Body (Main Body ECU RH)
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Illumination Rate Info Illumination information / 0 to 99.99 ms. 0.8 to 22 ms. -

    6. The value of the illumination rate should change in the following range when light shines on the automatic light control sensor or when the automatic light control sensor is covered.

      OK
      0.8 to 22 ms.

      Tech Tips

      This is the time taken for the automatic light control sensor to generate one cycle of frequency according to the brightness.


    OK

    REPLACE MAIN BODY ECU RH (COWL SIDE JUNCTION BLOCK RH)

    NG

  2. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU RH - AUTOMATIC LIGHT CONTROL SENSOR)


    1. A0162SFE09

      Disconnect the J74 main body ECU RH connector.

    2. Disconnect the K1 automatic light control sensor connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      J74-6 (CLTB) - K1-6 (CLTB) Always Below 1 Ω
      J74-5 (CLTS) - K1-5 (CLTS) Always Below 1 Ω
      J74-4 (CLTE) - K1-3 (CLTE) Always Below 1 Ω
      J74-6 (CLTB) - Body ground Always 10 kΩ or higher
      J74-5 (CLTS) - Body ground Always 10 kΩ or higher
      J74-4 (CLTE) - Body ground Always 10 kΩ or higher

    4. Connect the 2 connectors.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK AUTOMATIC LIGHT CONTROL SENSOR


    1. A0160MDE51

      Disconnect the automatic light control sensor.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      K1-3 (CLTE) - Body ground Always Below 1 Ω

    3. Connect the voltmeter's positive (+) lead to terminal 6 and the negative (-) lead to terminal 3.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      K1-3 (CLTE) - K1-6 (CLTB) Engine switch on (IG) 11 to 14 V

    5. Connect the K1 automatic light control sensor connector.

    6. A0162O9E02

      Connect the oscilloscope and check the waveform according to the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition Tester Range
      K1-3 (CLTE) - K1-5 (CLTS) Engine switch on (IG), Headlight dimmer switch in AUTO Correct waveform is as shown in the illustration 5 V/Division, 5 msec/Division

      If the ambient light becomes brighter, width A becomes narrower.


    NG

    REPLACE AUTOMATIC LIGHT CONTROL SENSOR Click here

    OK

    REPLACE MAIN BODY ECU RH (COWL SIDE JUNCTION BLOCK RH)