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Terminals Of Ecu

  1. CHECK MAIN BODY ECU (DRIVER SIDE JUNCTION BLOCK ASSEMBLY) 
    Fig 1: Identifying A68, L13 And DA Main Body ECU Connectors
    G05780653Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the A68, L13 and DA main body ECU connectors
    2. Measure the voltage and resistance according to the value(s) in the table below
      CONNECTOR TERMINAL REFERENCE

      Terminal No. (Symbols) Wiring Color Terminal Description Condition Specified Condition
      L13-6 (AM1) - Body ground W - Body ground +B power supply Always 11 to 14 V
      L12-1 (AM2) - Body ground W - Body ground +B power supply Always 11 to 14 V
      L13-17 (SSW1) - Body ground W - Body ground Power switch 1 input Power switch pushed Below 1 Ω
      L13-17 (SSW1) - Body ground W - Body ground Power switch 1 input Power switch not pushed 10 kΩ or higher
      L13-16 (SSW2) - Body ground L - Body ground Power switch 2 input Power switch pushed Below 1 Ω
      L13-16 (SSW2) - Body ground L - Body ground Power switch 2 input Power switch not pushed 10 kΩ or higher
      DA-40 (GND1) - Body ground W-B - Body ground Ground Always Below 1 Ω
      DA-23 or DA-52 (LIN1) - Body ground O - Body ground LIN line Always 10 kΩ or higher

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

    3. Reconnect the A68, L13 and DA main body ECU connectors
    4. Measure the voltages according to the value (s) in the table below.
      CONNECTOR TERMINAL REFERENCE

      Terminal No. (Symbols) Wiring Color Terminal Description Condition Specified Condition
      L13-22 (ACCD) - DA-40 (GND1) G - W-B D-ACC relay drive signal Power switch ON (ACC) 11 to 14 V
      L13-22 (ACCD) - DA-40 (GND1) G - W-B D-ACC relay drive signal Power switch OFF Below 1 V
      L12-11 (IG2D) - DA-40 (GND1) P - W-B Ignition relay No 2 (IG2) drive signal Power switch ON (IG) 11 to 14V
      L12-11 (IG2D) - DA-40 (GND1) P - W-B Ignition relay No 2 (1G2) drive signal Power switch ON (ACC) Below 1 V
      L13-19 (SLR+) - DA-40 (GND1) SB - W-B Steering lock power supply Steering lock motor operating Below 1 V
      L13-19 (SLR+) - DA-40 (GND1) SB - W-B Steering lock power supply Steering lock motor not operating 11 to 14 V
      L13-18 (SLP) - DA-40 (GND1) LG - W-B Steering lock actuator position signal Steering lock locked 11 to 14 V
      L13-18 (SLP) - DA-40 (GND1) LG - W-B Steering lock actuator position signal Steering lock released Below 1 V
      L11-9 (SPD) - DA-40 (GND1) V - W-B Speed signal from combination meter Power switch ON (IG), rotate driving wheel slowly Pulse generation (see  1waveform 1)
      L11-8 (RDY) - DA-40 (GND1) W - W-B Power switch ON (READY) signal Power switch ON (READY) Pulse generation (see  2waveform 2)
      A68-2 (P) - DA-40 (GND1) Y - W-B Shift lock signal Shift lever in P Pulse generation (see  3waveform 3)
      A68-2 (P) - DA-40 (GND1) Y - W-B Shift lock signal Shift lever not in P Below 1 V
      A68-4 (STSW) - DA-40 (GND1) B - W-B Hybrid control system activation request signal Brake pedal depressed with shift lever in P, power switch pushed once 11 to 14 V
      L13-15 (INDS) - DA-40 (GND1) B - W-B Vehicle condition signal Brake pedal depressed with shift lever in P, power switch OFF, ON (ACC, IG) 9 to 14 V
      L13-14 (INDW) - DA-40 (GND1) P - W-B Vehicle condition signal Brake pedal released with shift lever in P, power switch OFF, ON (ACC, IG) 9 to 14 V
      L13-25 (SWIL) - DA-40 (GND1) R - W-B Illumination signal Light control switch TAIL or HEAD 11 to 14 V
      DH-15 (STP) - DA-40 (GND1) L - W-B Stop light switch signal Brake pedal depressed 11 to 14 V
      DH-15 (STP) - DA-40 (GND1) L - W-B Stop light switch signal Brake pedal released Below 1 V

      If the result is not as specified, the ECU may have a malfunction.

    5. Using an oscilloscope, check the signal waveform of the ECU
      1. Waveform 1

        Reference 

        WAVEFORM REFERENCE 1

        Terminal No. (Symbols) Tool Setting Condition
        L11-9 (SPD) - DA-40 (GND1) 5V/DIV, 100msec/DIV Driving at approx 20 km/h (12mph)

        HINT:

        As the vehicle speed increases, the wavelength shortens.

        Fig 2: Waveform Graph 1
        G05630958Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      2. Waveform 2

        Reference 

        WAVEFORM REFERENCE 2

        Terminal No. (Symbols) Tool Setting Condition
        L11-8 (RDY) - DA-40 (GND1) 10V/DIV, 10msec/DIV Power switch ON (IG) or ON (READY)
        Fig 3: Waveform Graph 2
        G05780655Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. Waveform 3

        Reference 

        WAVEFORM REFERENCE 3

        Terminal No. (Symbols) Tool Setting Condition
        A68-2 (P) - DA-40 (GND1) 2 V/DIV, 20 msec /DIV Shift lever in P
  2. CHECK CERTIFICATION ECU 
    Fig 4: Waveform Graph 3
    G05630960Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    Fig 5: Identifying L15 Certification ECU Connector
    G05780657Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the L15 certification ECU connector
    2. Measure the voltage and resistance according to the value (s) in the table below
      CONNECTOR TERMINAL REFERENCE

      Terminal No. (Symbols) Wiring Color Terminal Description Condition Specified Condition
      L15-1 (+B1) - Body ground L - Body ground +B power supply Always 11 to 14 V
      L15-10 (LIN) - Body ground O - Body ground LIN line Always 10 kΩ or higher
      L15-17 (E) - 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 L15 certification ECU connector.
    4. Measure the voltage according to the value (s) in the table below
      CONNECTOR TERMINAL REFERENCE

      Terminal No (Symbols) Wiring Color Terminal Description Condition Specified Condition
      L15-18 (IG) - Body ground L - Body ground Ignition power supply Power switch ON (IG) 11 to 14V
      L15-18 (IG) - Body ground L - Body ground Ignition power supply Power switch OFF Below 1 V

      If the result is not as specified, the main body ECU may have malfunction.

  3. CHECK HYBRID VEHICLE CONTROL ECU 
    Fig 6: Identifying A74, A75, A76 And E55 Hybrid Vehicle Control ECU Connectors
    G05780658Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the A74, A75, A76 and E55 hybrid vehicle control ECU connectors
    2. Measure the voltage and resistance according to the value (s) in the table below.
      CONNECTOR TERMINAL REFERENCE

      Terminal No. (Symbols) Wiring Color Terminal Description Condition Specified Condition
      A74-1 (BATT) - A75-7 (E1) B-W - W-B Battery (for measuring battery voltage and for hybrid vehicle control ECU memory) Always 11 to 14 V
      A76-1 (+B1) - A75-7 (E1) B - W-B Power source of hybrid vehicle control ECU Power switch ON (IG) 11 to 14 V
      A74-4 (IGSW) - A75-7 (E1) R - W-B Power switch signal Always 11 to 14 V
      A75-7 (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 A74, A75, A76 and E55 hybrid vehicle control ECU connectors.
    4. Measure the voltage according to the value (s) in the table below
      CONNECTOR TERMINAL REFERENCE

      Terminal No. (Symbols) Wiring Color Terminal Description Condition Specified Condition
      A76-29 (RDY) - A75-7 (E1) W - W-B Hybrid control system ON (READY) signal (output) Power switch ON (READY) Pulse generation (see  1waveform 1)
      A76-28 (ST2) - A75-7 (E1) B - W-B Hybrid control system activation request signal Brake pedal depressed with shift lever in P, power switch pushed once 0 to 1 5 V

      If the result is not as specified, the hybrid vehicle control ECU may have a malfunction.

    5. Using an oscilloscope, check the signal waveform of the ECU.
      1. Waveform 1

        Reference 

        WAVEFORM REFERENCE 1

        Terminal No. (Symbols) Tool Setting Condition
        A76-29 (RDY) - A75-7 (E1) 10V/DIV, 10msec/DIV Power switch ON (IG) or ON (READY)
  4. CHECK STEERING LOCK ECU 
    Fig 7: Waveform Graph
    G05780655Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    Fig 8: Identifying L33 Steering Lock ECU Connector
    G05780660Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the L33 steering lock ECU connector.
    2. Measure the voltage and resistance according to the value (s) in the table below.
      CONNECTOR TERMINAL REFERENCE

      Terminal No. (Symbols) Wiring Color Terminal Description Condition Specified Condition
      L33-7 (B) - Body ground P - Body ground +B power supply Always 11 to 14 V
      L33-6 (IG2) - Body ground L - Body ground Ignition power supply Power switch ON (IG) 11 to 14 V
      L33-6 (IG2) - Body ground L - Body ground Ignition power supply Power switch OFF Below 1 V
      L33-1 (GND) - Body ground W-B - Body ground Ground Always Below 1 Ω
      L33-2 (SGND) - Body ground BR - 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 L33 steering lock ECU connector.
    4. Measure the voltage according to the value (s) in the table below.
      CONNECTOR TERMINAL REFERENCE

      Terminal No. (Symbols) Wiring Color Terminal Description Condition Specified Condition
      L33-4 (SLP1) - L33-1 (GND) LG - W-B Steering lock actuator position signal Steering is locked 11 to 14 V
      L33-4 (SLP1) - L33-1 (GND) LG - W-B Steering lock actuator position signal Steering is released Below 1 V

      If the result is not as specified, the ECU may have a malfunction.