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Terminals Of Ecu

  1. CHECK MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH) 
    Fig 1: Main Body ECU Connector Terminal Identification (Cowl Side Junction Block LH)
    GTY148653Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the E1, E2 and 2D main 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
      E1-6 (AM1) - Body ground W - Body ground +B power supply Always 11 to 14 V
      E2-1 (AM2) - Body ground W - Body ground +B power supply Always 11 to 14 V
      E1-17 (SSW1) - Body ground B - Body ground Engine switch 1 input Engine switch pushed Below 1 Ω
      E1-17 (SSW1) - Body ground B - Body ground Engine switch 1 input Engine switch not pushed 10 kΩ or higher
      E1-16 (SSW2) - Body ground B - Body ground Engine switch 2 input Engine switch pushed Below 1 Ω
      E1-16 (SSW2) - Body ground B - Body ground Engine switch 2 input Engine switch not pushed 10 kΩ or higher
      2D-62 (GND2) - Body ground W-B - Body ground Ground Always Below 1 Ω
      2D-20 (LIN1) - Body ground GR - 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 E1, E2 and 2D main body 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
      E1-22 (ACCD) - 2D-62 (GND2) P - W-B ACC relay drive signal Engine switch on (ACC) 11 to 14 V
      E1-22 (ACCD) - 2D-62 (GND2) P - W-B ACC relay drive signal Engine switch off Below 1 V
      E1-3 (IG1D) - 2D-62 (GND2) G - W-B IG1 No. 3 relay drive signal Engine switch on (IG) 11 to 14 V
      E1-3 (IG1D) - 2D-62 (GND2) G - W-B IG1 No. 3 relay drive signal Engine switch on (ACC) Below 1 V
      E2-11 (IG2D) - 2D-62 (GND2) B - W-B Integration relay (IG2 relay) drive signal Engine switch on (IG) 11 to 14 V
      E2-11 (IG2D) - 2D-62 (GND2) B - W-B Integration relay (IG2 relay) drive signal Engine switch on (ACC) Below 1 V
      E1-19 (SLR+) - 2D-62 (GND2) G - W-B Steering lock power supply Steering lock motor operating Below 1 V
      E1-19 (SLR+) - 2D-62 (GND2) G - W-B Steering lock power supply Steering lock motor not operating 11 to 14 V
      E1-8 (STR) - 2D-62 (GND2) L - W-B Park/neutral position switch signal Engine switch on (IG), shift lever not in P or N → P or N Below 2 V → Pulse generation*1
      E1-18 (SLP) - 2D-62 (GND2) SB - W-B Steering lock actuator position signal Steering lock locked 11 to 14 V
      E1-18 (SLP) - 2D-62 (GND2) SB - W-B Steering lock actuator position signal Steering lock released Below 1 V
      E3-9 (SPD) - 2D-62 (GND2) V - W-B Speed signal from combination meter Engine switch on (IG), driving wheel rotating slowly Pulse generation
      (see waveform 1 in step  1)
      E3-8 (TACH) - 2D-62 (GND2) W - W-B Tachometer signal Engine running Pulse generation
      (see waveform 2 in step  2)
      E4-2 (P) - 2D-62 (GND2) L - W-B Shift lock signal Shift lever in P Pulse generation
      (see waveform 3 in step  3)
      E4-2 (P) - 2D-62 (GND2) L - W-B Shift lock signal Shift lever not in P Below 1 V
      E4-4 (STSW) - 2D-62 (GND2) R - W-B Starter activation request signal Brake pedal depressed with shift lever in P, engine switch pushed once 11 to 14 V
      E1-15 (INDS) - 2D-62 (GND2) W - W-B Vehicle condition signal Brake pedal released with shift lever in P or N, engine switch off, on (ACC) or on (IG) 9 to 14 V
      E1-14 (INDW) - 2D-62 (GND2) W - W-B Vehicle condition signal Brake pedal released with shift lever in P or N, engine switch off, on (ACC) or on (IG) 9 to 14 V
      E1-25 (SWIL) - 2D-62 (GND2) R - W-B Illumination signal Light control switch tail or head 11 to 14 V
      2B-22 (STP) - 2D-62 (GND2) R - W-B Stop light switch signal Brake pedal depressed 11 to 14 V
      2B-22 (STP) - 2D-62 (GND2) R - W-B Stop light switch signal Brake pedal released Below 1 V

      HINT: 

      *1: Remove the ST CUT relay before measuring the voltage.

      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
        Fig 2: Identifying Waveform 1
        GTY138064Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        REFERENCE

        Terminal No. (Symbol) Tool Setting Condition
        E3-9 (SPD) - 2D-62 (GND2) 5 V/DIV., 100 msec./DIV. Vehicle driven at approx. 20 km/h (12 mph)

        HINT: 

        As the vehicle speed increases, the wavelength shortens.

      2. Waveform 2
        Fig 3: Identifying Waveform 2
        GTY121203Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        REFERENCE

        Terminal No. (Symbol) Tool Setting Condition
        E3-8 (TACH) - 2D-62 (GND2) 10 V/DIV., 10 msec./DIV. Engine switch on (IG) or engine started
      3. Waveform 3
        Fig 4: Identifying Waveform 3
        GTY133000Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        REFERENCE

        Terminal No. (Symbol) Tool Setting Condition
        E4-2 (P) - 2D-62 (GND2) 2 V/DIV., 20 msec./DIV. Shift lever in P
  2. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 
    Fig 5: Certification ECU Connector Terminal Identification (Smart Key ECU Assembly)
    GTY109860Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the E29 certification ECU (smart key ECU assembly) 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
      E29-1 (+B) - Body ground B - Body ground +B power supply Always 11 to 14 V
      E29-10 (LIN) - Body ground GR - Body ground LIN line Always 10 kΩ or higher
      E29-17 (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 E29 certification ECU (smart key ECU assembly) connector.
    4. Measure the voltage according to the value(s) in the table below.
      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      E29-18 (IG) - Body ground B - Body ground Ignition power supply Engine switch on (IG) 11 to 14 V
      E29-18 (IG) - Body ground B - Body ground Ignition power supply Engine switch off Below 1 V

      If the result is not as specified, the certification ECU (smart key ECU assembly) may have a malfunction.

  3. CHECK ECM 
    Fig 6: ECM Connector Terminal Identification
    GTY141224Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the A38 and C53 ECM 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
      A38-1 (BATT) - C53-81 (E1) L - W-B Battery (for measuring battery voltage and for ECM memory) Always 11 to 14 V
      A38-3 (+B) - C53-81 (E1) B - W-B Power source of ECM Engine switch on (IG) 11 to 14 V
      A38-28 (IGSW) - C53-81 (E1) B - W-B Engine switch signal Always 11 to 14 V
      C53-81 (E1) - Body ground W-B - Body ground Ground Always Below 1 Ω
      C53-43 (E01) - Body ground W-B - Body ground Ground Always Below 1 Ω
      C53-42 (E02) - Body ground BR - Body ground Ground Always Below 1 Ω
      C53-46 (E03) - Body ground W-B - Body ground Ground Always Below 1 Ω
      C53-23 (E04) - Body ground W-B - Body ground Ground Always Below 1 Ω
      C53-21 (E05) - 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 ECM connectors.
    4. Measure the voltage according to the value(s) in the table below.
      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      A38-46 (STA) - C53-81 (E1) R-B - W-B ST relay operation signal Cranking 5.5 V or higher
      A38-14 (STSW) - C53-81 (E1) R - W-B Starter activation request signal Brake pedal depressed, engine switch on (IG) Output voltage at terminal AM1 or AM2 is -2 V or higher
      A38-41 (ACCR) - C53-81 (E1) L-Y - W-B ACC relay cut signal
      (output)      		 Engine switch on (IG) → Cranking 11 to 14 V → Below 1 V
      A38-15 (TACH) - C53-81 (E1) W-G - W-B Engine speed signal
      (output)      		 Idling Pulse generation
      (see waveform 1 in step  e)
      C53-16 (STAR) - C53-81 (E1) L - W-B ST relay drive signal Cranking 11 to 14 V

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

    5. Using an oscilloscope, check the signal waveform of the ECM.
      Fig 7: Identifying Signal Waveform
      GTY129274Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      REFERENCE

      Terminal No. (Symbol) Tool Setting Condition
      A38-15 (TACH) - C53-81 (E1) 5 V/DIV., 10 ms./DIV. Engine idling

      HINT: 

      As the engine speed increases, the wavelength shortens.

  4. CHECK STEERING LOCK ECU 
    Fig 8: Steering Lock ECU Connector Terminal Identification
    GTY120075Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the E26 steering lock 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
      E26-7 (B) - Body ground R - Body ground +B power supply Always 11 to 14 V
      E26-6 (IG2) - Body ground B - Body ground Ignition power supply Engine switch on (IG) 11 to 14 V
      E26-6 (IG2) - Body ground B - Body ground Ignition power supply Engine switch off Below 1 V
      E26-1 (GND) - Body ground W-B - Body ground Ground Always Below 1 Ω
      E26-2 (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 E26 steering lock ECU connector.
    4. Measure the voltage according to the value(s) in the table below.
      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      E26-4 (SLP1) - E26-1 (GND) SB - W-B Steering lock actuator position signal Steering locked 11 to 14 V
      E26-4 (SLP1) - E26-1 (GND) SB - W-B Steering lock actuator position signal Steering released Below 1 V

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

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