LIGHTING SYSTEM, Diagnostic DTC:B1244

DTC Code DTC Name
B1244 Light Sensor Circuit Malfunction

DESCRIPTION

The automatic light control sensor detects ambient light, converts it into an electrical signal, and outputs it to the main body ECU. The main body ECU turns on or off the headlights and taillights according to the signal.

DTC No. DTC Detection Condition Trouble Area
B1244

  • Malfunction in automatic light control sensor

  • Open or short in automatic light control sensor circuit

  • Automatic light control sensor

  • Harness or connector

  • Main body ECU

WIRING DIAGRAM

A0117U9E01

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK FOR DTC


    1. Clear the DTC Click here.

    2. Recheck for DTC Click here.

      OK
      DTC B1244 is not output.

    NG

    READ VALUE USING INTELLIGENT TESTER Click here

    OK

    USE SIMULATION METHOD TO CHECK Click here

  2. READ VALUE USING INTELLIGENT TESTER


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the tester on.

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

    5. According to the display on the tester, read the Data List.

      Main Body
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Illumination Rate Info

      Illumination rate

      Min.: 0 ms.

      Max.: 99.99 ms.

      		 Actual illumination rate is displayed -
      OK
      Output illumination is as shown in table above.

    NG

    INSPECT AUTOMATIC LIGHT CONTROL SENSOR (SYSTEM VOLTAGE) Click here

    OK

    REPLACE MAIN BODY ECU Click here

  3. INSPECT AUTOMATIC LIGHT CONTROL SENSOR (SYSTEM VOLTAGE)


    1. A011A48E17
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Automatic Light Control Sensor)

      Disconnect the T1 automatic light control sensor connector.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      T1-3 (CLTB) - T1-6 (CLTE) Ignition switch ON 11 to 14 V
      Ignition switch off Below 1 V

    3. Reconnect the automatic light control sensor connector.


    NG

    CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - AUTOMATIC LIGHT CONTROL SENSOR) Click here

    OK

    REPLACE AUTOMATIC LIGHT CONTROL SENSOR Click here

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


    1. A0119T9E02
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Main Body ECU)
      *2

      Front view of wire harness connector

      (to Automatic Light Control Sensor)

      Disconnect the D42 main body ECU connector.

    2. Disconnect the T1 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
      D42-20 (CLTB) - T1-3 (CLTB) Always Below 1 Ω
      D42-20 (CLTB) - Body ground Always 10 kΩ or higher
      D42-21 (CLTS) - T1-4 (CLTS) Always Below 1 Ω
      D42-21 (CLTS) - Body ground Always 10 kΩ or higher
      D42-22 (CLTE) - T1-6 (CLTE) Always Below 1 Ω
      D42-22 (CLTE) - Body ground Always 10 kΩ or higher

    4. Reconnect the automatic light control sensor connector.

    5. Reconnect the main body ECU connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE MAIN BODY ECU Click here