LIGHTING SYSTEM TERMINALS OF ECU


  1. CHECK INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY AND MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

    B004PUPC17
    *A Main Body ECU (Multiplex Network Body ECU) with 1 Connector - -
    B004PLRC15
    *A Main Body ECU (Multiplex Network Body ECU) with 2 Connectors - -

    1. Disconnect the instrument panel junction block assembly and main body ECU (multiplex network body ECU) connectors.

    2. Measure the voltage on the wire harness side connector according to the value(s) in the table below.

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      3F-1 - Body ground W - Body ground Auxiliary battery power supply Power switch off 11 to 14 V
      3K-1 - Body ground B-R - Body ground Auxiliary battery power supply Power switch off 11 to 14 V

      If the result is not as specified, there may be a malfunction in the wire harness.

    3. Measure the resistance on the wire harness side connector according to the value(s) in the table below.

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      3D-3 - Body ground W-B - Body ground Ground Always Below 1 Ω

      If the result is not as specified, there may be a malfunction in the wire harness.

    4. Reconnect the instrument panel junction block assembly and main body ECU (multiplex network body ECU) connectors.

    5. Measure the voltage and check for pulses according to the value(s) in the table below.

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      3H-30 - Body ground G - Body ground Taillights and license plate lights drive output Light control switch in tail or head position 11 to 14 V
      Light control switch off*2 position Below 1 V
      3A-52 - Body ground BE - Body ground Front fog light drive output Light control switch in tail or head position, fog light switch in front position Below 1 V
      Light control switch in tail or head position, fog light switch off position 11 to 14 V
      3H-21 - Body ground*1 B - Body ground Rear fog light drive output Light control switch in tail or head position, fog light switch in rear position 11 to 14 V
      Light control switch in tail or head position, fog light switch off position Below 1 V
      3F-31 - Body ground G - Body ground H-LP LH relay drive output Power switch off 11 to 14 V
      Power switch on (IG) Below 1 V
      F17-1 (DIM) - Body ground BE - Body ground H-LP RH relay drive output Power switch off 11 to 14 V
      Power switch on (IG) Below 1 V
      F17-8 (A) - Body ground W - Body ground Light control switch AUTO position signal input Light control switch in AUTO position Below 1 V
      Light control switch not in AUTO position Pulse generation
      F17-10 (HF) - Body ground SB - Body ground Dimmer switch high flash position signal input Dimmer switch in high flash position Below 1 V
      Dimmer switch not in high flash position Pulse generation
      F17-12 (HEAD) - Body ground G - Body ground Light control switch head position input Light control switch in head position Below 1 V
      Light control switch not in head position Pulse generation
      F17-19 (CLTB) - F17-21 (CLTE) BR - G Automatic light control sensor power supply output Power switch off Below 1 V
      Power switch on (IG 11 to 14 V
      F17-20 (CLTS) - Body ground R - Body ground Automatic light control sensor signal input Power switch off Below 1 V
      Automatic light control system operating

      Communication waveform generation

      (See waveform 1)
      F17-22 (TAIL) - Body ground BE - Body ground Light control switch tail position signal input Light control switch in tail or head position Below 1 V
      Light control switch not in tail or head position Pulse generation
      F17-23 (RFOG) - Body ground*1 W - Body ground Fog light switch rear position input Fog light switch in rear position Below 1 V
      Fog light switch off position Pulse generation
      F17-24 (HU) - Body ground P - Body ground Dimmer switch high position signal input Dimmer switch in high position Below 1 V
      Dimmer switch not in high position Pulse generation
      F17-26 (FFOG) - Body ground GR - Body ground Fog light switch front position input Fog light switch in front position Below 1 V
      Fog light switch off position Pulse generation

      • *1: w/ Rear Fog Light

      • *2: w/ Light Contorol Switch off Position

      If the result is not as specified, the main body ECU (multiplex network body ECU) or instrument panel junction block assembly may be malfunctioning.


      1. B004PMTN01

        Waveform 1

        Item Content
        Tool setting 2 V/DIV., 10 ms./DIV.

        Tech Tips

        The communication waveform changes according to the surrounding brightness.

  2. CHECK NO. 1 HEADLIGHT ECU SUB-ASSEMBLY LH

    B004PXXN09

    1. Disconnect the A18 No. 1 headlight ECU sub-assembly LH connector.

    2. Measure the resistance and voltage on the wire harness side connector according to the value(s) in the table below.

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      A18-4 (IG) - Body ground V - Body ground Ignition power supply Power switch off Below 1 V
      Power switch on (IG) 11 to 14 V
      A18-13 (ECUB) - Body ground R - Body ground Auxiliary battery power supply Power switch off Below 1 V
      Power switch on (IG) 11 to 14 V
      A18-12 (GND) - Body ground W-B - Body ground Ground Always Below 1 Ω

    3. Reconnect the A18 No. 1 headlight ECU sub-assembly LH connector.

      Tech Tips


      • Since the A18 No. 1 headlight ECU sub-assembly LH connector is a waterproof type connector, the voltage cannot be measured and pulses cannot be checked for directly. The values listed are for reference only.

      • Since the B No. 1 headlight ECU sub-assembly LH connector is connected inside the headlight assembly, the voltage cannot be measured and pulses cannot be checked for directly. The values listed are for reference only.

    4. Measure the voltage and check of pulses according to the value(s) in the table below.

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      A18-8 (RLD2) - Body ground G - Body ground Daytime running light LH drive output Daytime running light LH off Pulse generation
      Daytime running light LH on Below 1.8 V
      A18-16 (SBR) - A18-15 (SGR) G - R Rear height control sensor RR LH power supply Power switch on (IG) 4.75 to 5.25 V
      A18-17 (SHRL) - A18-15 (SGR) L - R Rear height control RR LH signal input Power switch on (IG), vehicle unloaded, vehicle stopped

      Approximately 2.5 V

      (value decreases as the front of the vehicle is raised)
      A18-20 (LINL) - Body ground BE - Body ground LIN communication line Power switch off Below 1 V
      Power switch on (IG) Pulse generation
      B-1 (HI-) - B-10 (HI+) - High beam headlights drive output High beam headlights off Below 1 V
      High beam headlights on 11 to 14 V
      B-4 (LOLED2) - B-5 (LOLED1) - Low beam headlights/high beam headlights drive output Low beam headlights and high beam headlights off Below 1 V
      Low beam headlights or high beam headlights on 11.2 to 17.7 V
      B-6 (FANB) - B-14 (FANG) - Headlight fan power source Low beam headlights off Below 1 V
      Low beam headlights on 4.5 to 5.5 V
      B-7 (ACTBI) - B-17 (ACTGI) - Headlight leveling motor power source Power switch off Below 1 V
      Power switch on (IG) 11 to 14 V
      B-8 (ACTSI) - B-17 (ACTGI) - Headlight leveling motor signal output Power switch on (IG), low beam headlights on, vehicle height not changed Below 1 V
      Power switch on (IG), low beam headlights on, vehicle height changed and maintained for more than 3 seconds 1.0 to 14 V
      B-14 (FANG) - B-15 (FANP) - Headlight fan control signal input Low beam headlights off Below 1 V
      Low beam headlights on Pulse generation
      B-2 (CLL-) - B-19 (CLL+) - Clearance lights drive output Clearance lights off Below 1 V
      Clearance lights on 11 to 14 V

  3. CHECK NO. 1 HEADLIGHT ECU SUB-ASSEMBLY RH

    B004PXXN10

    1. Disconnect the A19 No. 1 headlight ECU sub-assembly RH connector.

    2. Measure the resistance and voltage on the wire harness side connector according to the value(s) in the table below.

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      A19-4 (IG) - Body ground V - Body ground Ignition power supply Power switch off Below 1 V
      Power switch on (IG) 11 to 14 V
      A19-13 (ECUB) - Body ground L - Body ground Auxiliary battery power supply Power switch off Below 1 V
      Power switch on (IG) 11 to 14 V
      A19-12 (GND) - Body ground W-B - Body ground Ground Always Below 1 Ω

    3. Reconnect the A19 No. 1 headlight ECU sub-assembly RH connector.

      Tech Tips


      • Since the A19 No. 1 headlight ECU sub-assembly RH connector is a waterproof type connector, the voltage cannot be measured and pulses cannot be checked for directly. The values listed are for reference only.

      • Since the B No. 1 headlight ECU sub-assembly RH connector is connected inside the headlight assembly, the voltage cannot be measured and pulses cannot be checked for directly. The values listed are for reference only.

    4. Measure the voltage and check of pulses according to the value(s) in the table below.

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      A19-8 (RLD2) - Body ground L - Body ground Daytime running light RH drive output Daytime running light RH off Pulse generation
      Daytime running light RH on Below 1.8 V
      A19-20 (LINL) - Body ground BE - Body ground LIN communication line Power switch off Below 1 V
      Power switch on (IG) Pulse generation
      B-1 (HI-) - B-10 (HI+) - High beam headlights drive output High beam headlights off Below 1 V
      High beam headlights on 11 to 14 V
      B-4 (LOLED2) - B-5 (LOLED1) - Low beam headlights/high beam headlights drive output Low beam headlights and high beam headlights off Below 1 V
      Low beam headlights or high beam headlights on 11.2 to 17.7 V
      B-6 (FANB) - B-14 (FANG) - Headlight fan power source Low beam headlights off Below 1 V
      Low beam headlights on 4.5 to 5.5 V
      B-7 (ACTBI) - B-17 (ACTGI) - Headlight leveling motor power source Power switch off Below 1 V
      Power switch on (IG) 11 to 14 V
      B-8 (ACTSI) - B-17 (ACTGI) - Headlight leveling motor signal output Power switch on (IG), low beam headlights on, vehicle height not changed Below 1 V
      Power switch on (IG), low beam headlights on, vehicle height changed and maintained for more than 3 seconds 1.0 to 14 V
      B-14 (FANG) - B-15 (FANP) - Headlight fan control signal input Low beam headlights off Below 1 V
      Low beam headlights on Pulse generation
      B-2 (CLL-) - B-19 (CLL+) - Clearance lights drive output Clearance lights off Below 1 V
      Clearance lights on 11 to 14 V

  4. CHECK COMBINATION METER ASSEMBLY

    Click here

  5. CHECK HYBRID VEHICLE CONTROL ECU

    Click here