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Terminals Of Ecu [03/2019 - ]

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  1. CHECK MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) AND INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY 
    Fig 1: Multiplex Network Body ECU Connector Terminal Identification
    GTY795133Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the instrument panel junction block assembly and main body ECU (multiplex network body ECU) connectors.
    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
      4B-7 - Body ground W-B - Body ground Ground Always Below 1 Ω
      4E-1 - Body ground B - Body ground Battery power supply Always 11 to 14 V
      4F-1 - Body ground B - Body ground Battery power supply Always 11 to 14 V
    3. Connect the instrument panel junction block assembly and main body ECU (multiplex network body ECU) connectors.
    4. 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
      4C-5 - Body ground B - Body ground Front side marker light drive output Light control switch in tail or head position 11 to 14 V
      Light control switch off Below 1 V
      4C-10 - Body ground GR - Body ground BKUP LP relay drive output Engine switch off Below 1 V
      Engine switch on (IG) 11 to 14 V
      4C-15 - Body ground GR - Body ground Parking brake switch input Parking brake switch on Below 1 V
      Parking brake switch off 11 to 14 V
      4C-18 - Body ground G - Body ground BKUP LP relay drive output Engine switch off, reverse (R) not selected Below 1 V
      Engine switch on (IG), reverse (R) selected 11 to 14 V
      4C-20 - Body ground B - Body ground BKUP LP relay drive output Engine switch off Below 1 V
      Engine switch on (ACC) 11 to 14 V
      4C-29 - Body ground R - Body ground H-LP LH relay drive output Light control switch in head position Below 1 V
      Light control switch not in head position 11 to 14 V
      4D-22 - Body ground B - Body ground BKUP LP relay drive output Engine switch off, reverse (R) not selected Below 1 V
      Engine switch on (IG), reverse (R) selected 11 to 14 V
      4D-28 - Body ground V - Body ground Taillight drive output Light control switch in tail or head position 11 to 14 V
      Light control switch off Below 1 V
      O1-4 (MILE) - Body ground LG - Body ground Outside handle foot lights drive output Outside handle foot light illuminates 11 to 14 V
      Outside handle foot light off Below 3 V
      O2-1 (DIM) - Body ground V - Body ground H-LP RH relay drive output Light control switch in head position Below 1 V
      Light control switch not in head position 11 to 14 V
      O2-8 (A) - Body ground P - 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
      O2-10 (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
      O2-12 (HEAD) - Body ground Y - 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
      O2-19 (CLTB) - O2-21 (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
      O2-20 (CLTS) - Body ground R - Body ground Automatic light control sensor signal input Engine switch off Below 1 V
      Engine switch on (IG) Pulse generation
      (See waveform 1)
      O2-22 (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
      O2-24 (HU) - Body ground V - Body ground Dimmer switch high position signal input Dimmer switch in high position Below 1 V
      Dimmer switch not in high position Pulse generation
      1. Waveform 1
        Fig 2: Waveform 1
        GTY442965Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        Item Content
        Tester Connection O2-20 (CLTS) - Body ground
        Tool setting 2 V/DIV., 10 ms./DIV.
        Condition Engine switch on (IG)

        HINT: 

        The communication waveform changes according to the surrounding brightness.

  2. CHECK HEADLIGHT ECU SUB-ASSEMBLY LH (for Triple Beam Headlight) 
    Fig 3: A3 Headlight ECU Sub-Assembly LH Connector
    GTY959388Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the A3 headlight ECU sub-assembly LH connector.
    2. Measure the voltage and 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
      A3-4 (IG) - Body ground B - Body ground Ignition power supply Engine switch off Below 1 V
      Engine switch on (IG) 11 to 14 V
      A3-12 (GND) - Body ground W-B - Body ground Ground Always Below 1 Ω
      A3-13 (ECUB) - Body ground W - Body ground Battery power supply Engine switch off Below 1 V
      Engine switch on (IG) 11 to 14 V
    3. Connect the A3 headlight ECU sub-assembly LH connector.

      HINT: 

      • Since the A3 headlight ECU sub-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 and C headlight ECU sub-assembly LH connectors are 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 for pulses according to the value(s) in the table below.
      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      A3-11 (TNS) - Body ground G - Body ground Front turn signal light signal input Engine switch on (IG), front turn signal light off Below 1 V
      Engine switch on (IG), front turn signal light blinking 11 to 14 V ←→ Below 1 V
      A3-16 (SBR) - A3-15 (SGR) GR - LG Rear height control sensor sub-assembly power supply Engine switch on (IG) 4.75 to 5.25 V
      A3-17 (SHRL) - A3-15 (SGR) G - LG Rear height control sensor sub-assembly signal input Engine switch on (IG), vehicle unloaded, vehicle stopped Approximately 2.5 V
      (value decreases as the front of the vehicle is raised)
      A3-20 (LINL) - Body ground LG - Body ground LIN communication line Engine switch on (IG) Pulse generation
      A3-23 (CANL) - Body ground B - Body ground CAN communication line Engine switch off Below 1 V
      Engine switch on (IG) Pulse generation
      A3-24 (CANH) - Body ground V - Body ground CAN communication line Engine switch off Below 1 V
      Engine switch on (IG) Pulse generation
      B-4 (LOLED2) - B-5 (LOLED1) - Low beam headlights/high beam headlights drive output Low beam headlights off Below 1 V
      Low beam headlights on 11.1 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 Engine switch off Below 1 V
      Engine switch on (IG) 11 to 14 V
      B-8 (ACTSI) - B-17 (ACTGI) - Headlight leveling motor signal output Engine switch on (IG), low beam headlights on, vehicle height not changed Below 1 V
      Engine switch on (IG), low beam headlights on, vehicle height changed and maintained for more than 3 seconds 1.0 to 14 V
      B-9 (TURN+) - B-13 (TURN-) - Front turn signal light signal output Engine switch on (IG), front turn signal light off Below 1 V
      Engine switch on (IG), front turn signal light blinking 11 to 14 V ←→ Below 1 V
      B-10 (HI+) - B-1 (HI-) - Parking lights/daytime running lights power source Parking lights and daytime running lights off Below 1 V
      Parking lights and daytime running lights on 11 to 14 V
      B-15 (FANP) - B-14 (FANG) - Headlight fan control signal input Low beam headlights off Below 1 V
      Low beam headlights on Pulse generation
      B-16 (PWM1) - B-1 (HI-) - Parking lights/daytime running lights control signal output Parking lights and daytime running lights off Below 1 V
      Parking lights and daytime running lights on Pulse generation
      B-20 (DRL+) - B-11 (DRL-) - High beam headlights drive output High beam headlights off Below 1 V
      High beam headlights on 11 to 14 V
      C-8 (HILED2) - C-9 (HILED1) - Low beam headlights/high beam headlights drive output Low beam headlights off Below 1 V
      Low beam headlights on 11.1 to 17.7 V
  3. CHECK HEADLIGHT ECU SUB-ASSEMBLY LH (for Single Beam Headlight) 
    Fig 4: A3 Headlight ECU Sub-Assembly LH Connector
    GTY959324Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the A3 headlight ECU sub-assembly LH connector.
    2. Measure the voltage and 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
      A3-4 (IG) - Body ground B - Body ground Ignition power supply Engine switch off Below 1 V
      Engine switch on (IG) 11 to 14 V
      A3-12 (GND) - Body ground W-B - Body ground Ground Always Below 1 Ω
      A3-13 (ECUB) - Body ground W - Body ground Battery power supply Engine switch off Below 1 V
      Engine switch on (IG) 11 to 14 V
    3. Connect the A3 headlight ECU sub-assembly LH connector.

      HINT: 

      • Since the A3 headlight ECU sub-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 ECU sub-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 for pulses according to the value(s) in the table below.
      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      A3-11 (TNS) - Body ground G - Body ground Front turn signal light signal input Engine switch on (IG), front turn signal light off Below 1 V
      Engine switch on (IG), front turn signal light blinking 11 to 14 V ←→ Below 1 V
      A3-16 (SBR) - A3-15 (SGR) GR - LG Rear height control sensor sub-assembly power supply Engine switch on (IG) 4.75 to 5.25 V
      A3-17 (SHRL) - A3-15 (SGR) G - LG Rear height control sensor sub-assembly signal input Engine switch on (IG), vehicle unloaded, vehicle stopped Approximately 2.5 V
      (value decreases as the front of the vehicle is raised)
      A3-20 (LINL) - Body ground LG - Body ground LIN communication line Engine switch on (IG) Pulse generation
      A3-23 (CANL) - Body ground B - Body ground CAN communication line Engine switch off Below 1 V
      Engine switch on (IG) Pulse generation
      A3-24 (CANH) - Body ground V - Body ground CAN communication line Engine switch off Below 1 V
      Engine switch on (IG) Pulse generation
      B-4 (LOLED2) - B-5 (LOLED1) - Low beam headlights/high beam headlights drive output Low beam headlights off Below 1 V
      Low beam headlights on 11.1 to 17.7 V
      B-7 (ACTBI) - B-17 (ACTGI) - Headlight leveling motor power source Engine switch off Below 1 V
      Engine switch on (IG) 11 to 14 V
      B-8 (ACTSI) - B-17 (ACTGI) - Headlight leveling motor signal output Engine switch on (IG), low beam headlights on, vehicle height not changed Below 1 V
      Engine switch on (IG), low beam headlights on, vehicle height changed and maintained for more than 3 seconds 1.0 to 14 V
      B-9 (TURN+) - B-13 (TURN-) - Front turn signal light signal output Engine switch on (IG), front turn signal light off Below 1 V
      Engine switch on (IG), front turn signal light blinking 11 to 14 V ←→ Below 1 V
      B-10 (HI+) - B-1 (HI-) - Parking lights/daytime running lights power source Parking lights and daytime running lights off Below 1 V
      Parking lights and daytime running lights on 11 to 14 V
      B-16 (PWM1) - B-1 (HI-) - Parking lights/daytime running lights control signal output Parking lights and daytime running lights off Below 1 V
      Parking lights and daytime running lights on Pulse generation
      B-20 (DRL+) - B-11 (DRL-) - High beam headlights drive output High beam headlights off Below 1 V
      High beam headlights on 11 to 14 V
  4. CHECK HEADLIGHT ECU SUB-ASSEMBLY RH (for Triple Beam Headlight) 
    Fig 5: A11 Headlight ECU Sub-assembly RH Connector
    GTY959399Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the A11 headlight ECU sub-assembly RH connector.
    2. Measure the voltage and 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
      A11-4 (IG) - Body ground B - Body ground Ignition power supply Engine switch off Below 1 V
      Engine switch on (IG) 11 to 14 V
      A11-12 (GND) - Body ground W-B - Body ground Ground Always Below 1 Ω
      A11-13 (ECUB) - Body ground B - Body ground Battery power supply Engine switch off Below 1 V
      Engine switch on (IG) 11 to 14 V
    3. Connect the A11 headlight ECU sub-assembly RH connector.

      HINT: 

      • Since the A11 headlight ECU sub-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 and C headlight ECU sub-assembly RH connectors are 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 for pulses according to the value(s) in the table below.
      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      A11-11 (TNS) - Body ground R - Body ground Front turn signal light signal input Engine switch on (IG), front turn signal light off Below 1 V
      Engine switch on (IG), front turn signal light blinking 11 to 14 V ←→ Below 1 V
      A11-20 (LINL) - Body ground LG - Body ground LIN communication line Engine switch on (IG) Pulse generation
      B-4 (LOLED2) - B-5 (LOLED1) - Low beam headlights/high beam headlights drive output Low beam headlights off Below 1 V
      Low beam headlights on 11.1 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 Engine switch off Below 1 V
      Engine switch on (IG) 11 to 14 V
      B-8 (ACTSI) - B-17 (ACTGI) - Headlight leveling motor signal output Engine switch on (IG), low beam headlights on, vehicle height not changed Below 1 V
      Engine switch on (IG), low beam headlights on, vehicle height changed and maintained for more than 3 seconds 1.0 to 14 V
      B-9 (TURN+) - B-13 (TURN-) - Front turn signal light signal output Engine switch on (IG), front turn signal light off Below 1 V
      Engine switch on (IG), front turn signal light blinking 11 to 14 V ←→ Below 1 V
      B-10 (HI+) - B-1 (HI-) - Parking lights/daytime running lights power source Parking lights and daytime running lights off Below 1 V
      Parking lights and daytime running lights on 11 to 14 V
      B-15 (FANP) - B-14 (FANG) - Headlight fan control signal input Low beam headlights off Below 1 V
      Low beam headlights on Pulse generation
      B-16 (PWM1) - B-1 (HI-) - Parking lights/daytime running lights control signal output Parking lights and daytime running lights off Below 1 V
      Parking lights and daytime running lights on Pulse generation
      B-20 (DRL+) - B-11 (DRL-) - High beam headlights drive output High beam headlights off Below 1 V
      High beam headlights on 11 to 14 V
      C-8 (HILED2) - C-9 (HILED1) - Low beam headlights/high beam headlights drive output Low beam headlights off Below 1 V
      Low beam headlights on 11.1 to 17.7 V
  5. CHECK HEADLIGHT ECU SUB-ASSEMBLY RH (for Single Beam Headlight) 
    Fig 6: A11 Headlight ECU Sub-Assembly RH Connector
    GTY959362Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the A11 headlight ECU sub-assembly RH connector.
    2. Measure the voltage and 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
      A11-4 (IG) - Body ground B - Body ground Ignition power supply Engine switch off Below 1 V
      Engine switch on (IG) 11 to 14 V
      A11-12 (GND) - Body ground W-B - Body ground Ground Always Below 1 Ω
      A11-13 (ECUB) - Body ground B - Body ground Battery power supply Engine switch off Below 1 V
      Engine switch on (IG) 11 to 14 V
    3. Connect the A11 headlight ECU sub-assembly RH connector.

      HINT: 

      • Since the A11 headlight ECU sub-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 ECU sub-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 for pulses according to the value(s) in the table below.
      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      A11-11 (TNS) - Body ground R - Body ground Front turn signal light signal input Engine switch on (IG), front turn signal light off Below 1 V
      Engine switch on (IG), front turn signal light blinking 11 to 14 V ←→ Below 1 V
      A11-20 (LINL) - Body ground LG - Body ground LIN communication line Engine switch on (IG) Pulse generation
      B-4 (LOLED2) - B-5 (LOLED1) - Low beam headlights/high beam headlights drive output Low beam headlights off Below 1 V
      Low beam headlights on 11.1 to 17.7 V
      B-7 (ACTBI) - B-17 (ACTGI) - Headlight leveling motor power source Engine switch off Below 1 V
      Engine switch on (IG) 11 to 14 V
      B-8 (ACTSI) - B-17 (ACTGI) - Headlight leveling motor signal output Engine switch on (IG), low beam headlights on, vehicle height not changed Below 1 V
      Engine switch on (IG), low beam headlights on, vehicle height changed and maintained for more than 3 seconds 1.0 to 14 V
      B-9 (TURN+) - B-13 (TURN-) - Front turn signal light signal output Engine switch on (IG), front turn signal light off Below 1 V
      Engine switch on (IG), front turn signal light blinking 11 to 14 V ←→ Below 1 V
      B-10 (HI+) - B-1 (HI-) - Parking lights/daytime running lights power source Parking lights and daytime running lights off Below 1 V
      Parking lights and daytime running lights on 11 to 14 V
      B-16 (PWM1) - B-1 (HI-) - Parking lights/daytime running lights control signal output Parking lights and daytime running lights off Below 1 V
      Parking lights and daytime running lights on Pulse generation
      B-20 (DRL+) - B-11 (DRL-) - High beam headlights drive output High beam headlights off Below 1 V
      High beam headlights on 11 to 14 V
  6. CHECK COMBINATION METER ASSEMBLY 

    Refer to TERMINALS OF ECU [03/2019 - ]

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