LIGHTING SYSTEM TERMINALS OF ECU


  1. CHECK COWL SIDE JUNCTION BLOCK LH AND MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

    B002EKLC57
    *1 Main Body ECU (Multiplex Network Body ECU) - -

    1. Remove the main body ECU (multiplex network body ECU) from the cowl side junction block LH.

      Click here

    2. Connect the cowl side junction block LH connectors.

    3. 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
      MB-32 (IG) - Body ground - Ignition power supply Engine switch on (IG) 11 to 14 V
      MB-30 (BECU) -Body ground - Battery power supply Always 11 to 14 V
      MB-29 (ACC) - Body ground - ACC power supply Engine switch on (ACC) 11 to 14 V
      MB-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 passenger side junction block.

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

      Click here

    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
      5D-11 - Body ground W - Body ground Taillight drive output Light control switch in tail or head position 11 to 14 V
      Light control switch off Below 1 V
      5D-9 - Body ground Y - Body ground LH LAMP relay drive output Light control switch in tail or head position Below 1 V
      Light control switch off 11 to 14 V
      5C-16 - Body ground*1 GR - 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 Below 1 V
      5D-21 - Body ground LG - Body ground RH LAMP relay drive output Light control switch in tail or head position Below 1 V
      Light control switch off 11 to 14 V
      K11-5 (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
      K11-8 (HF) - Body ground L - 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
      K11-20 (CLTB) - K11-22 (CLTE) GR - W Automatic light control sensor power supply output Engine switch off Below 1 V
      Engine switch on (IG), light control switch in AUTO position 11 to 14 V
      K11-21 (CLTS) - Body ground R - Body ground Automatic light control sensor signal input Engine switch off Below 1 V
      Automatic light control system operating

      Communication waveform generation

      (See waveform 1)
      K12-23 (RFOG) - Body ground*1 GR - Body ground Fog light switch rear position input Fog light switch in rear position Below 1 V
      Fog light switch off Pulse generation
      K11-28 (A) - Body ground R - 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
      K11-29 (HEAD) - Body ground LG - 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
      K11-30 (TAIL) - Body ground B - 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

      • *1: w/ Rear Fog Light

      If the result is not as specified, the main body ECU (multiplex network body ECU) or cowl side junction block LH may be malfunctioning.


      1. B002DNSN01

        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 HEADLIGHT CONTROL COMPUTER ASSEMBLY LH

    B002EVME01

    1. Disconnect the A29 headlight control computer 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
      A29-4 (IG) - Body ground LG - Body ground Ignition power supply Engine switch off Below 1 V
      Engine switch on (IG) 11 to 14 V
      A29-13 (ECUB) - Body ground G - Body ground Battery power supply Light control switch off Below 1 V
      Light control switch in tail or head position 11 to 14 V
      A29-12 (GND) - Body ground W-B - Body ground Ground Always Below 1 Ω

    3. Reconnect the A29 headlight control computer assembly LH connector.

      Tech Tips


      • Since the A29 headlight control computer assembly LH connector is a waterproof type connector, the voltage and pulses cannot be checked directly. The values listed are for reference only.

      • Since the B headlight control computer assembly LH connector is connected inside the headlight assembly, the voltage and pulses cannot be checked 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
      A29-11 (TNS) - Body ground B - Body ground LH turn signal light signal input Engine switch on (IG), LH turn signal light off Below 1 V
      Engine switch on (IG), LH turn signal light blinking 11 to 14 V ←→ Below 1 V
      A29-16 (SBR) - A29-15 (SGR) R - B Rear height control sensor power supply Engine switch on (IG) 4.75 to 5.25 V
      A29-17 (SHRL) - A29-15 (SGR) P - B Rear height control sensor signal input Engine switch on (IG), vehicle unloaded, vehicle stopped

      Approximately 2.5 V

      (value decreases as the front of the vehicle is raised)
      A29-20 (LINL) - Body ground B - Body ground LIN communication Engine switch on (IG) Pulse generation
      B-1 - B-10*1 - High beam headlights drive output High beam headlights off Below 1 V
      High beam headlights on 11 to 14 V
      B-3 - B-4 - 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 - B-14 - Headlight fan power source Low beam headlights off Below 1 V
      Low beam headlights on 4.5 to 5.5 V
      B-7 - B-17 - Headlight leveling motor power source Engine switch off Below 1 V
      Engine switch on (IG) 11 to 14 V
      B-9 - B-13 - Left turn signal light signal output Engine switch on (IG), LH turn signal light off Below 1 V
      Engine switch on (IG), LH turn signal light blinking 11 to 14 V ←→ Below 1 V
      B-11 - B-16 - Daytime running lights/clearance lights duty control signal output Daytime running lights/clearance lights on Pulse generation
      B-15 - B-14 - Headlight fan duty control signal input Low beam headlights off Below 1 V
      Low beam headlights on Pulse generation
      B-11 - B-20 - Daytime running lights/clearance lights power source Daytime running lights and clearance lights off Below 1 V
      Daytime running lights or clearance lights on 11 to 14 V
      C-7 - C8 - High beam headlights power source High beam headlights off Below 1 V
      High beam headlights on

      6 to 15 V*1

      16.05 to 25.65 V*2
      C-13 - Body ground - LIN communication Engine switch on (IG) Pulse generation

      • *1 w/ Adaptive High Beam System

      • *2 w/o Adaptive High Beam System

  3. CHECK HEADLIGHT CONTROL COMPUTER ASSEMBLY RH

    B002EVME02

    1. Disconnect the A30 headlight control computer 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
      A30-4 (IG) - Body ground LG - Body ground Ignition power supply Engine switch off Below 1 V
      Engine switch on (IG) 11 to 14 V
      A30-13 (ECUB) - Body ground B - Body ground Battery power supply Light control switch off Below 1 V
      Light control switch in tail or head position 11 to 14 V
      A30-12 (GND) - Body ground W-B - Body ground Ground Always Below 1 Ω

    3. Reconnect the A30 headlight control computer assembly RH connector.

      Tech Tips


      • Since the A30 headlight control computer assembly RH connector is a waterproof type connector, the voltage and pulses cannot be checked directly. The values listed are for reference only.

      • Since the B headlight control computer assembly RH connector is connected inside the headlight assembly, the voltage and pulses cannot be checked 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
      A30-11 (TNS) - Body ground Y - Body ground LH turn signal light signal input Engine switch on (IG), LH turn signal light off Below 1 V
      Engine switch on (IG), LH turn signal light blinking 11 to 14 V ←→ Below 1 V
      A30-20 (LINL) - Body ground B - Body ground LIN communication Engine switch on (IG) Pulse generation
      B-1 - B-10*1 - High beam headlights drive output High beam headlights off Below 1 V
      High beam headlights on 11 to 14 V
      B-3 - B-4 - 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 - B-14 - Headlight fan power source Low beam headlights off Below 1 V
      Low beam headlights on 4.5 to 5.5 V
      B-7 - B-17 - Headlight leveling motor power source Engine switch off Below 1 V
      Engine switch on (IG) 11 to 14 V
      B-9 - B-13 - Left turn signal light signal output Engine switch on (IG), LH turn signal light off Below 1 V
      Engine switch on (IG), LH turn signal light blinking 11 to 14 V ←→ Below 1 V
      B-11 - B-16 - Daytime running lights/clearance lights duty control signal output Daytime running lights/clearance lights on Pulse generation
      B-15 - B-14 - Headlight fan duty control signal input Low beam headlights off Below 1 V
      Low beam headlights on Pulse generation
      B-11 - B-20 - Daytime running lights/clearance llights power source Daytime running lights and clearance lights off Below 1 V
      Daytime running lights or clearance lights on 11 to 14 V
      C-7 - C8 - High beam headlights power source High beam headlights off Below 1 V
      High beam headlights on

      6 to 15 V*1

      16.05 to 25.65 V*2
      C-13 - Body ground - LIN communication Engine switch on (IG) Pulse generation

      • *1 w/ Adaptive High Beam System

      • *2 w/o Adaptive High Beam System

  4. CHECK COMBINATION METER ASSEMBLY

    B002EVZE08

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

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      K32-4 (ER) - Body ground B - Body ground Turn signal switch right signal input Turn signal switch in neutral position 11 to 14 V
      Turn signal switch in right turn position Below 1 V
      K32-5 (EL) - Body ground L - Body ground Turn signal switch left signal input Turn signal switch in neutral position 11 to 14 V
      Turn signal switch in left turn position Below 1 V
      K32-11 (HZSW) - Body ground P - Body ground Hazard warning signal switch signal (Input) Engine switch on (IG), hazard warning signal switch not pressed 11 to 14 V
      Engine switch on (IG), hazard warning signal switch pressed Below 1 V
      K32-12 (HAZM) - Body ground SB - Body ground Hazard warning signal switch signal (Output) Engine switch on (IG), hazard warning signal switch not pressed 11 to 14 V
      Engine switch on (IG), hazard warning signal switch pressed Below 1 V