LIGHTING 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

      If the result is not as specified, there may be a malfunction in the wire harness or instrument panel junction block assembly.

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

      for LHD:

      Click hereClick here

      for RHD:

      Click hereClick here

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

      Terminal No. (Symbol)

      Wiring Color

      Terminal Description

      Condition

      Specified Condition

      G78-1 (RFOG) - Body ground*1

      L - Body ground

      Rear fog light switch input

      Rear fog light switch on

      Below 1 V

      Rear fog light switch off

      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*8

      11 to 14 V*9

      G78-8 (HF) - Body ground

      R - Body ground

      Headlight dimmer switch high flash signal input

      Headlight dimmer switch in high flash position

      Below 1 V

      Headlight dimmer switch not in high flash position

      11 to 14 V

      G78-19 (FRCY) - Body ground*2

      GR - Body ground

      Front door courtesy light switch RH signal

      Front door RH open

      Below 1 V

      Front door RH closed

      Pulse generation

      G78-20 (CLTB) - G78-22 (CLTE)*3

      W - V

      Automatic light control sensor power supply output

      Power switch off

      Below 1 V

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

      11 to 14 V

      G78-21 (CLTS) - Body ground*3

      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)

      G78-27 (FFOG) - Body ground*4

      GR - Body ground

      Front fog light switch input

      Front fog light switch on

      Below 1 V

      Front fog light switch off

      Pulse generation*8

      11 to 14 V*9

      G78-28 (A) - Body ground*3

      G - Body ground

      Headlight dimmer switch AUTO signal input

      Headlight dimmer switch in AUTO position

      Below 1 V

      Headlight dimmer switch not in AUTO position

      Pulse generation*8

      11 to 14 V*9

      G78-29 (HEAD) - Body ground

      L - Body ground

      Headlight dimmer switch head signal input

      Headlight dimmer switch in head position

      Below 1 V

      Headlight dimmer switch not in head position

      11 to 14 V

      G78-30 (TAIL) - Body ground

      W - Body ground

      Headlight dimmer switch tail signal input

      Headlight dimmer switch in tail or head position

      Below 1 V

      Headlight dimmer switch in neither tail nor head position

      11 to 14 V

      G79-21 (RLEW) - Body ground

      SB - Body ground

      Light control signal input

      Power switch on (IG), headlight dimmer switch not in head position

      Pulse generation

      Power switch on (IG), headlight dimmer switch off

      11 to 14 V

      G79-24 (LLEW) - Body ground

      L - Body ground

      Light control signal input

      Power switch on (IG), headlight dimmer switch not in head position

      Pulse generation

      Power switch on (IG), headlight dimmer switch off

      11 to 14 V

      3B-37 (HRLY) - Body ground

      BR - Body ground

      H-LP relay drive output

      Headlight dimmer switch in head position

      Below 1 V

      Headlight dimmer switch not in head position

      11 to 14 V

      3B-52 (DRLE) - Body ground*6

      B - Body ground

      DRL relay drive output

      Daytime running light on

      Below 1 V

      Daytime running light off

      11 to 14 V

      3D-10 (DRLE) - Body ground*7

      B - Body ground

      DRL relay drive output

      Daytime running light on

      Below 1 V

      Daytime running light off

      11 to 14 V

      3B-54 (DIM) - Body ground

      LG - Body ground

      Running light 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

      3B-56 (FFGO) - Body ground*4

      W - Body ground

      Front fog light signal output

      Headlight dimmer switch in tail position and front fog light switch on

      Below 1 V

      Front fog light switch off

      11 to 14 V

      3D-34 (PKB) - Body ground

      B - Body ground

      Parking brake switch input

      Parking brake switch on

      Below 1 V

      Parking brake switch off

      11 to 14 V

      3D-52 (RFGO) - Body ground*1

      W - Body ground

      Rear fog light signal output

      Headlight dimmer switch in tail position and rear fog light switch on

      Below 1 V

      Rear fog light switch off

      11 to 14 V

      3E-40 (FLCY) - Body ground*5

      W - Body ground

      Front door courtesy light switch LH signal

      Front door LH open

      Below 1 V

      Front door LH closed

      Pulse generation

      *1: w/ Rear Fog Light

      *2: for RHD

      *3: w/ Automatic Light Control System

      *4: w/ Front Fog Light

      *5: for LHD

      *6: w/ Front Power Seat Control System (w/ Memory)

      *7: w/ Front Power Seat Control System (w/o Memory)

      *8: Main Body ECU (multiplex network body ECU) with 3 Connectors

      *9: 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 COMBINATION METER ASSEMBLY

    E235640N04

    1. Disconnect the G16 and G17 combination meter connectors.

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

      Terminal No. (Symbol)

      Wiring Color

      Terminal Description

      Condition

      Specified Condition

      G16-21 (ET) - Body ground

      BR - Body ground

      Ground

      Always

      Below 1 Ω

      G16-39 (IG+) - Body ground

      B - Body ground

      Ignition power supply

      Power switch off

      Below 1 V

      Power switch on (IG)

      11 to 14 V

      G16-40 (B) - Body ground

      Y - Body ground

      Battery power supply

      Power switch off

      11 to 14 V

      G17-1 (B) - Body ground

      L - Body ground

      Battery power supply

      Power switch off

      11 to 14 V

    3. Reconnect the G16 and G17 combination meter connectors.

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

      Terminal No. (Symbol)

      Wiring Color

      Terminal Description

      Condition

      Specified Condition

      G16-29 (HAZ) - Body ground

      BE - Body ground

      Headlight dimmer switch (turn signal switch) left or right turn position signal input

      Power switch on (IG), headlight dimmer switch (turn signal switch) off

      11 to 14 V

      Power switch on (IG), headlight dimmer switch (turn signal switch) in left or right turn position

      Below 1 V

      G17-3 (HAZ) - Body ground

      GR - Body ground

      Hazard warning signal switch signal input

      Hazard warning signal switch off

      11 to 14 V

      Hazard warning signal switch on

      Below 1 V

      G17-9 (ER) - Body ground

      SB - Body ground

      Headlight dimmer switch (turn signal switch) right turn position signal input

      Power switch on (IG), headlight dimmer switch (turn signal switch) off

      11 to 14 V

      Power switch on (IG), headlight dimmer switch (turn signal switch) in right turn position

      Below 1 V

      G17-10 (EL) - Body ground

      LG - Body ground

      Headlight dimmer switch (turn signal switch) left turn position signal input

      Power switch on (IG), headlight dimmer switch (turn signal switch) off

      Below 1 V

      Power switch on (IG), headlight dimmer switch (turn signal switch) in right turn position

      Below 1 V ←→ 11 to 14 V

      G17-7 (LR) - Body ground

      L - Body ground

      RH turn signal light signal output

      Power switch on (IG), RH turn signal light off

      Below 1 V

      Power switch on (IG), RH turn signal light blinking

      Below 1 V ←→ 11 to 14 V

      G17-13 (LL) - Body ground

      Y - Body ground

      LH turn signal light signal output

      Power switch on (IG), LH turn signal light off

      Below 1 V

      Power switch on (IG), LH turn signal light blinking

      Below 1 V ←→ 11 to 14 V