AUTOMATIC HIGH BEAM SYSTEM TERMINALS OF ECU

  1. C278789N02
    C278790C04

    *A

    Main Body ECU (Multiplex Network Body ECU) with 1 connector

    *B

    Main Body ECU (Multiplex Network Body ECU) with 3 connectors

    *1

    Main Body ECU (Multiplex Network Body ECU)

    -

    -

    CHECK INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY, MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

    1. Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.

      for LHD:

      Click here

      for RHD:

      Click here

    2. Connect the instrument panel junction block assembly connectors.

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

      Terminal No. (Symbol)

      Wiring Color

      Terminal Description

      Condition

      Specified Condition

      A-32 (IG) - Body ground

      -

      Ignition power supply

      Power switch on (IG)

      11 to 14 V

      Power switch off

      Below 1 V

      A-30 (BECU) - Body ground

      -

      Battery power supply

      Power switch off

      11 to 14 V

      A-29 (ACC) - Body ground

      -

      ACC power supply

      Power switch on (ACC)

      11 to 14 V

      Power switch off

      Below 1 V

      A-11 (GND1) - Body ground

      -

      Ground

      Always

      Below 1 Ω

    4. Install the main body ECU (multiplex network body ECU).

      for LHD:

      Click hereClick here

      for RHD:

      Click here

    5. Measure the voltage and pulse according to the value(s) in the table below.

      Terminal No. (Symbol)

      Wiring Color

      Terminal Description

      Condition

      Specified Condition

      3B-54 (DIM) - Body ground

      LG - Body ground

      DIMMER relay drive output

      Headlight dimmer switch in high or high flash position

      Below 1 V

      Headlight dimmer switch not in high or high flash position

      11 to 14 V

      G78-5 (HU) - Body ground

      Y - Body ground

      Headlight dimmer switch high signal input

      Headlight dimmer switch in high position

      Below 1 V

      Headlight dimmer switch in low position

      Pulse generation*1

      11 to 14 V*2

      G78-20 (CLTB) - G78-22 (CLTE)

      W - V

      Automatic light control sensor power supply output

      Power switch off

      Below 1 V

      Power switch on (IG), headlight dimmer switch in AUTO position

      11 to 14 V

      G78-21 (CLTS) - Body ground

      G - Body ground

      Automatic light control sensor signal input

      Power switch off

      Below 1 V

      Power switch on (IG), headlight dimmer switch in AUTO position, automatic light control sensor covered with a hand → Automatic light control sensor exposed to ambient light

      Pulse generation (See waveform 1)

      G78-28 (A) - Body ground

      G - Body ground

      Headlight dimmer switch AUTO position signal input

      Headlight dimmer switch in AUTO position

      Below 1 V

      Headlight dimmer switch not in AUTO position

      Pulse generation*1

      11 to 14 V*2

      *1: Main body ECU (multiplex network body ECU) with 3 connectors

      *2: Main body ECU (multiplex network body ECU) with 1 connector

      1. B113714E01

        Waveform 1

        Item

        Content

        Terminal No. (Symbol)

        G78-21 (CLTS) - Body ground

        Tool setting

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

        Condition

        Power switch on (IG), headlight dimmer switch in AUTO position, automatic light control sensor covered with a hand → Automatic light control sensor exposed to ambient light
        Tip:

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

  2. CHECK FORWARD RECOGNITION CAMERA

    1. Check the forward recognition camera.

      Click here