LIGHTING SYSTEM TERMINALS OF ECU


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

    A01IRG4E64
    A01IP4DE10

    1. Disconnect the DB, DE, DF and H80 ECU 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
      DB-30 (BECU) - Body ground W - Body ground Battery power supply Always 11 to 14 V
      DF-5 (ACC) - Body ground W - Body ground ACC power supply Ignition switch ACC 11 to 14 V
      Ignition switch off Below 1 V
      DE-28 (GND1) - Body ground W-B - Body ground Ground Always Below 1 Ω
      H80-4 (GND2) - Body ground W-B - Body ground Ground Always Below 1 Ω

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

    3. Reconnect the DB, DE, DF and H80 ECU connectors.

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

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      DJ-4 (HU) - DE-28 (GND1) P - W-B Dimmer switch high signal input Dimmer switch in high Below 1 V
      Dimmer switch in low 11 to 14 V

      H79-3 (DRLE) - DE-28 (GND1)*1,*2

      H81-14 (DRLE) - DE-28 (GND1)*1,*3

      		 W - W-B DRL relay drive output Daytime running light on Below 1 V
      Daytime running light off 11 to 14 V
      H79-20 (HRLY) - DE-28 (GND1) B - W-B H-LP relay drive output Light control switch in head Below 1 V
      Light control switch not in head 11 to 14 V
      H79-21 (TAIL) - DE-28 (GND1) W - W-B Light control switch tail signal input Light control switch in tail or head Below 1 V
      Light control switch in neither tail nor head 11 to 14 V
      H79-22 (HF) - DE-28 (GND1) R - W-B Dimmer switch high flash signal input Dimmer switch in high flash position Below 1 V
      Dimmer switch not in high flash position 11 to 14 V
      H80-11 (RFGO) - DE-28 (GND1) GR - W-B Rear fog light relay drive output Light control switch in head and rear fog light switch on Below 1 V
      Light control switch in head and rear fog light switch off 11 to 14 V
      H80-12 (DIM) - DE-28 (GND1) LG - W-B Dimmer relay drive output Dimmer switch in high or high flash Below 1 V
      Dimmer switch not in high or high flash 11 to 14 V
      H80-15 (CLTS) - DE-28 (GND1)*4 V - W-B Automatic light control sensor signal input Ignition switch off Below 1 V
      Automatic light control system operates

      Pulse generation

      (See waveform 1)
      H81-9 (RFOG) - DE-28 (GND1) SB - W-B Rear fog light switch input Rear fog light switch on Below 1 V
      Rear fog light switch off 11 to 14 V
      H81-12 (HEAD) - DE-28 (GND1) L - W-B Light control switch head signal input Light control switch in head Below 1 V
      Light control switch not in head 11 to 14 V
      H81-13 (FFOG) - DE-28 (GND1)*5 B - W-B Front fog light switch input Front fog light switch on Below 1 V
      Front fog light switch off 11 to 14 V
      H81-17 (FFGO) - DE-28 (GND1)*5 R - W-B Front fog light relay drive output Light control switch in tail and front fog light switch on Below 1 V
      Front fog light switch off 11 to 14 V
      H81-18 (A) - DE-28 (GND1)*4 V - W-B Light control switch AUTO signal input Light control switch in AUTO Below 1 V
      Light control switch not in AUTO 11 to 14 V
      DG-1 (TRLY) - DE-28 (GND1) W - W-B Battery power supply Always 11 to 14 V
      DC-5 (PKB) - DE-28 (GND1)*1 P - W-B Parking brake switch input Parking brake switch on Below 1 V
      Parking brake switch off 11 to 14 V
      DB-33 (TRLY) - DE-28 (GND1) GR - W-B Clearance light LH signal output Light control switch in tail position 11 to 14 V
      Light control switch not in tail position Below 1 V
      DB-15 (TRLY) - DE-28 (GND1) G - W-B Clearance light RH signal output Light control switch in tail position 11 to 14 V
      Light control switch not in tail position Below 1 V
      DA-29 (TRLY) - DE-28 (GND1) G - W-B Taillight signal output Light control switch in tail position 11 to 14 V
      Light control switch not in tail position Below 1 V
      DS-17 (HAZ) - DE-28 (GND1) B - W-B Hazard warning signal switch input Hazard warning signal switch on Below 1 V
      Hazard warning signal switch off 11 to 14 V

      • *1: w/ Daytime Running Light

      • *2: for LHD

      • *3: for RHD

      • *4: w/ Automatic Light Control System

      • *5: w/ Front Fog Light


      1. A01IQGPE01

        Waveform 1

        Item Content
        Terminal No. (Symbol) H80-15 (CLTS) - DE-28 (GND1)
        Tool setting 5 V/DIV., 5 ms./DIV.
        Condition

        Ignition switch ON

        Headlight dimmer switch AUTO

        Rain sensor covered with a hand → Rain sensor exposed to ambient light

        Tech Tips

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

  2. CHECK HEADLIGHT LEVELING ECU (for HID Headlight)

    A01IP9GE10

    1. Disconnect the A49 ECU connector.

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

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      A49-1 (IG) - Body ground G - Body ground Ignition power supply Ignition switch off Below 1 V
      Ignition switch ON 11 to 14 V
      A49-9 (E1) - Body ground W-B - Body ground Ground Always Below 1 Ω

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

    3. Reconnect the A49 ECU connector.

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

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      A49-3 (B2) - A49-9 (E1) B - W-B Low beam headlight signal input Low beam headlights on Below 1 V
      Low beam headlights off 11 to 14 V
      A49-5 (PRST) - A49-9 (E1) GR - W-B Initialization signal input Terminal LVL and terminal GND of DLC3 connected Below 1 V
      Terminal LVL and terminal GND of DLC3 not connected Approximately 5 V
      A49-6 (WNG) - A49-9 (E1) GR - W-B Warning indicator drive output Warning indicator on 11 to 14 V
      Warning indicator off Below 1 V
      A49-10 (RHT) - A49-9 (E1) LG - W-B Leveling motor RH power supply Ignition switch off Below 1 V
      Ignition switch ON 11 to 14 V
      A49-11 (LHT) - A49-9 (E1) W - W-B Leveling motor LH power supply Ignition switch off Below 1 V
      Ignition switch ON 11 to 14 V
      A49-12 (SBR) - A49-21 (SGR) R - BR Rear height control sensor power supply Ignition switch off Below 1 V
      Ignition switch ON 4.75 to 5.25 V
      A49-16 (SPDR) - A49-9 (E1) V - W-B Vehicle speed signal input Vehicle is driven at approximately 20 km/h (12 mph)

      Pulse generation

      (See waveform 1)
      A49-17 (RH+) - A49-9 (E1) P - W-B Leveling motor RH operation signal input With low beam headlights on, vehicle height not changed Below 1 V
      With low beam headlights on, vehicle height changed and maintained for more than 3 seconds 1.0 to 14.4 V
      A49-18 (LH+) - A49-9 (E1) BR-W - W-B Leveling motor LH operation signal input With low beam headlights on, vehicle height not changed Below 1 V
      With low beam headlights on, vehicle height changed and maintained for more than 3 seconds 1.0 to 14.4 V
      A49-19 (SHRL) - A49-21 (SGR) Y - BR Rear height control sensor signal input Ignition switch off Below 1 V
      Ignition switch ON 0.5 to 4.5 V
      A49-21 (SGR) - A49-9 (E1) BR - W-B Rear height control sensor ground Always Below 1 Ω
      A49-23 (RH-) - A49-9 (E1) W-B - W-B Leveling motor RH ground Always Below 1 Ω
      A49-24 (LH-) - A49-9 (E1) B - W-B Leveling motor LH ground Always Below 1 Ω

      1. A01IQ7DE03

        Waveform 1

        Item Content
        Terminal No. (Symbol) A49-16 (SPDR) - A49-9 (E1)
        Tool setting 5 V/DIV., 20 ms./DIV.
        Condition Vehicle is driven at approximately 20 km/h (12 mph)

        Tech Tips

        When the system is functioning normally, one wheel revolution generates 4 pulses. As the vehicle speed increases, the width indicated by (A) in the illustration narrows.