LIGHTING SYSTEM, Diagnostic DTC:B1244

DTC Code DTC Name
B1244 Light Sensor Circuit Malfunction

DESCRIPTION

The automatic light control sensor detects ambient light. The sensor creates an electrical signal based on the amount of light detected, and sends the signal to the main body ECU (multiplex network body ECU). The main body ECU (multiplex network body ECU) turns on or off the headlights and taillights according to the signal.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

B1244

Light Sensor Circuit Malfunction

  • 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 (multiplex network body ECU)

WIRING DIAGRAM

E223761E09

PROCEDURE

  1. READ VALUE USING GTS

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

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

    5. Read the display on the GTS.

      Body Electrical > Main Body > Data List

      Tester Display

      Measurement Item

      Range

      Normal Condition

      Diagnostic Note

      Illumination Rate Info

      Illumination rate information

      0.00 ms. to 2162.65 ms.

      Value is output according to ambient light level

      -

      Body Electrical > Main Body > Data List

      Tester Display

      Illumination Rate Info

      OK

      Normal condition listed above is displayed.

    Result

    Proceed to

    OK

    NG
    OK

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

    for LHD:Click hereClick here

    for RHD:Click hereClick here

    NG

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

    1. Disconnect the F2 automatic light control sensor connector.

    2. Disconnect the E22 main body ECU (multiplex network body ECU) connector.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      E22-22 (CLTE) - F2-3 (CLTE)

      Always

      Below 1 Ω

      E22-21 (CLTS) - F2-4 (CLTS)

      Always

      Below 1 Ω

      E22-20 (CLTB) - F2-1 (CLTB)

      Always

      Below 1 Ω

      E22-22 (CLTE) - Body ground

      Always

      10 kΩ or higher

      E22-21 (CLTS) - Body ground

      Always

      10 kΩ or higher

      E22-20 (CLTB) - Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. INSPECT MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

    1. E173035C10

      *a

      Component with harness connected

      (Main Body ECU (Multiplex Network Body ECU))

      Reconnect the E22 main body ECU (multiplex network body ECU) connector.

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

      Standard Voltage

      Tester Connection

      Condition

      Specified Condition

      E22-20 (CLTB) - E22-22 (CLTE)

      Ignition switch off

      Below 1 V

      Ignition switch ON

      11 to 14 V

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      E22-22 (CLTE) - Body ground

      Always

      Below 1 Ω

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

    for LHD:Click hereClick here

    for RHD:Click hereClick here

    OK

  4. INSPECT AUTOMATIC LIGHT CONTROL SENSOR

    1. E259596C02

      *a

      Component with harness connected

      (Automatic Light Control Sensor)

      Reconnect the F2 automatic light control sensor connector.

    2. Connect an oscilloscope to the automatic light control sensor connector.

    3. B113714N01

      Check the waveform.

      OK

      Tester Connection

      Tool Setting

      Condition

      Specified Condition

      F2-3 (CLTE) - F2-4 (CLTS)

      5 V/DIV., 5 ms./DIV.

      Ignition switch ON, light control switch in AUTO position

      Correct waveform is as shown
      Tip:

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

    Result

    Proceed to

    OK

    NG
    OK

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

    for LHD:Click hereClick here

    for RHD:Click hereClick here

    NG

    REPLACE AUTOMATIC LIGHT CONTROL SENSOR

    Click hereClick here