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 Code DTC Detection Condition Trouble Area
B1244

When either condition below is met:


  • Malfunction of light sensor

  • Open or short of light sensor circuit

  • Automatic light control sensor

  • Main body ECU

  • Harness or connector

WIRING DIAGRAM

A00103DE10
*a Automatic Light Control Sensor
*b Main Body ECU

PROCEDURE


  1. CHECK FOR DTC


    1. Clear the DTC Click here.

    2. Check for DTC Click here.

      OK
      DTC B1244 output does not occur.

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

  2. READ VALUE USING GTS (AUTOMATIC LIGHT CONTROL SENSOR)


    1. Using the GTS, read the Data List.

      Main Body
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Illumination Rate Info Condition of automatic light control sensor/0 to 2162.65 ms Condition value will be displayed -
      OK
      Output illuminance is as shown in table above.

    OK

    REPLACE MAIN BODY ECU

    NG

  3. CHECK MAIN BODY ECU (CLTB - CLTE VOLTAGE)

    A000XYKE01
    *1 Component with harness connected: (Main Body ECU)

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

      Standard voltage
      Tester Connection Switch Condition Specified Condition
      L12-20 (CLTB) - L12-18 (CLTE) Power switch ON (IG) 11 to 14 V

    NG

    REPLACE MAIN BODY ECU

    OK

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

    A000XOBE04
    *1 Front view of wire harness connector: (to Main Body ECU)
    *2 Front view of wire harness connector: (to Automatic Light Control Sensor)

    1. Disconnect the L12 ECU connector.

    2. Disconnect the M2 sensor connector.

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

      Standard resistance
      Tester Connection Condition Specified Condition
      L12-20 (CLTB) - M2-6 (CLTB) Always Below 1 Ω
      L12-19 (CLTS) - M2-5 (CLTS)
      L12-18 (CLTE) - M2-3 (CLTE)
      L12-20 (CLTB) - Body ground Always 10 kΩ or higher
      L12-19 (CLTS) - Body ground
      L12-18 (CLTE) - Body ground

    OK

    REPLACE AUTOMATIC LIGHT CONTROL SENSOR Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR