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Terminals Of Ecu

  1. CHECK POWER SOURCE CONTROL ECU 
    Fig 1: Identifying Terminals Of K73 Power Source Control ECU Connector
    G05287851Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the K73 ECU connector.
    2. Measure the voltage and resistance of the wire harness side connector.
      TERMINALS REFERENCE CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      AM1 (K73-33) - Body ground O - Body ground +B power supply Always 10 to 14 V
      AM2(K73-12)-Body ground BR - Body ground +B power supply Always 10 to 14 V
      SSW1 (K73-14)-Body ground P - Body ground Power switch signal Power switch pushed Below 1 Ω
      SSW1 (K73-14) - Body ground P - Body ground Power switch signal Power switch not pushed 10 kΩ or higher
      SSW2 (K73-37) - Body ground B - Body ground Power switch signal Power switch pushed Below 1Ω
      SSW2 (K73-37) - Body ground B - Body ground Power switch signal Power switch not pushed 10 kΩ or higher
      GND2 (K73-6) - Body ground W-B - Body ground Ground Always Below 1Ω
      LIN1 (K73-30) - Body ground W - 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 K73 ECU connector.
    4. Measure the voltage of the connector.
      TERMINALS REFERENCE CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      ACCD (K73-11) - GND2 (K73-6) G-W-B ACC relay actuation signal Power switch ON (ACC) 10 to 14 V
      ACCD (K73-11) - GND2 (K73-6) G-W-B ACC relay actuation signal Power switch OFF Below 1 V
      IG1D (K73-34) - GND2 (K73-6) P-W-B IG1 relay actuation signal Power switch ON (IG) 10 to 14 V
      IG1D (K73-34) - GND2 (K73-6) P-W-B IG1 relay actuation signal Power switch ON (ACC) Below 1 V
      IG2D (K73-35) - GND2 (K73-6) LG - W-B IG2 relay actuation signal Power switch ON (IG) 10 to 14 V
      IG2D (K73-35) - GND2 (K73-6) LG - W-B IG2 relay actuation signal Power switch ON (ACC) Below 1 V
      STP (K73-1) - GND2 (K73-6) V-W-B Stop light signal Brake pedal depressed 10 to 14 V
      STP (K73-1) - GND2 (K73-6) V-W-B Stop light signal Brake pedal released Below 1 V
      SLR+ (K73-32) - GND2 (K73-6) LG - W-B Steering lock motor power supply permit signal Power supply to steering lock motor permitted Below 1 V
      SLR+ (K73-32) - GND2 (K73-6) LG - W-B Steering lock motor power supply permit signal Power supply to steering lock motor stopped 10 to 14 V
      SLP (K73-26) - GND2 (K73-6) V - W-B Steering lock actuator position signal Steering lock is locked Pulse generation (see WAVEFORM 1 REFERENCE waveform 1)
      SLP (K73-26) - GND2 (K73-6) V - W-B Steering lock actuator position signal Steering lock is released Below 1 V
      SPD (K73-19) - GND2 (K73-6) L-W-B Vehicle speed signal Power switch ON (IG), rotate rear wheel slowly Pulse generation (see WAVEFORM 2 REFERENCE waveform 2)
      P (K73-5) - GND2 (K73-6) LG - W-B Shift lock signal Shift lever P position Pulse generation (see WAVEFORM 3 REFERENCE waveform 3)
      P (K73-5) - GND2 (K73-6) LG - W-B Shift lock signal Shift lever not P position Below 1 V
      STSW (K73-39) - GND2 (K73-6) Y - W-B HV start request signal Power switch pressed with brake pedal depressed → After approx. 1 sec. has passed, release power switch 10 to 14V → Below 1 V
      INDS (K73-4) - GND2 (K73-6) SB - W-B HV start OK signal Brake pedal depressed, shift lever P position, power switch ON (ACC, IG) 10 to 14 V
      INDW (K73-13) - GND2 (K73-6) R - W-B HV start NG signal Brake pedal released, shift lever P position, power switch ON (ACC, IG) 10 to 14 V
      SWIL (K73-36) - GND2 (K73-6) GR - W-B Illumination signal Light control switch TAIL or HEAD 10 to 14 V
      SKSW (K73-28) - GND2 (K73-6) L - W-B ACC signal Power switch ON (ACC, IG) Below 1 V
      RDY (K73-22) - GND2 (K73-6) W - W-B READY signal Power switch ON (READY) Pulse generation (see WAVEFORM 4 REFERENCE waveform 4)
      RDY (K73-22) - GND2 (K73-6) W - W-B READY signal Power switch OFF, ON (ACC), ON (IG) Pulse generation (see WAVEFORM 4 REFERENCE waveform 4)

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

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

      Waveform 1 (Reference): 

      WAVEFORM 1 REFERENCE

      Item Content
      Symbols (Terminal No.) SLP (K73-26) - GND2 (K73-6)
      Tool Setting 2V/DIV., 100 msec./DIV.
      Vehicle Condition Steering lock is locked
      Fig 2: Identifying Waveform 1
      G05303599Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Waveform 2 (Reference): 

      WAVEFORM 2 REFERENCE

      Item Content
      Symbols (Terminal No.) SPD (K73-19) - GND2 (K73-6)
      Tool Setting 5V/DIV., 100msec./DIV.
      Vehicle Condition Driving at approx. 20 km/h (12 mph)

      HINT:

      As the vehicle speed increases, the wavelength shortens.

      Fig 3: Identifying Waveform 2
      G05303600Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Waveform 3 (Reference): 

      WAVEFORM 3 REFERENCE

      Item Content
      Symbols (Terminal No.) P (K73-5) - GND2 (K73-6)
      Tool Setting 2 V/DIV., 20 msec./DIV.
      Vehicle Condition Shift lever P position
      Fig 4: Identifying Waveform 3
      G05303601Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Waveform 4 (Reference): 

      WAVEFORM 4 REFERENCE

      Item Content
      Symbols (Terminal No.) RDY (K73-22) - GND2 (K73-6)
      Tool Setting 10 V/DIV., 10 msec./DIV.
      Vehicle Condition Power switch ON (IG) or ON (READY)
      6. Fig 5: Identifying Waveform 4
      G05303602Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. CHECK CERTIFICATION ECU 
    Fig 6: Identifying Terminals Of U28 And U33 ECU Connectors
    G05287854Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the U28 and U33 ECU connectors.
    2. Measure the voltage and resistance of the wire harness side connector.
      TERMINALS REFERENCE CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      +B1 (U28-1) - Body ground R - Body ground +B power supply Always 10 to 14 V
      IG (U28-18) - Body ground B - Body ground Ignition power supply Power switch ON (IG) 10 to 14 V
      IG (U28-18) - Body ground B - Body ground Ignition power supply Power switch OFF Below 1 V
      LIN (U28-10) - Body ground LG - Body ground LIN line Always 10 kΩ or higher
      E(U28-17) - 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. CHECK STEERING LOCK ECU 
    Fig 7: Identifying Terminals Of K28 Steering Lock ECU Connector
    G05814556Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the K28 ECU connector.
    2. Measure the voltage and resistance of the wire harness side connector.
      TERMINALS REFERENCE CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      B (K28-7) - Body ground L - Body ground +B power supply Always Always
      IG2 (K28-6) - Body ground B - Body ground Ignition power supply Power switch ON (IG) Always
      IG2 (K28-6) - Body ground B - Body ground Ignition power supply Power switch OFF Below 1 V
      GND(K28-1) - Body ground W-B - Body ground Ground Always Below 1 Ω
      SGND (K28-2) - 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 K28 ECU connector.
    4. Measure the voltage of the connector.
      TERMINALS REFERENCE CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      SLP1 (K28-4) - GND (K28-1) V-W-B Steering lock actuator position signal Steering is locked 10 to 14 V
      SLP1 (K28-4) - GND (K28-1) V-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.

  4. CHECK ECM 
    Fig 8: Identifying Terminals Of A53 And E83 ECM Connectors
    G05303605Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the A53 and E83 ECM connectors.
    2. Measure the voltage and resistance of the wire harness side connectors.
      TERMINALS REFERENCE CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      +B (A53-2) - Body ground B-R - Body ground Power source of ECM Power switch ON (IG) 10 to 14 V
      +B1 (A53-1) - Body ground B-R - Body ground Power source of ECM Power switch ON (IG) 10 to 14 V
      IGSW (A53-11) - Body ground B-W - Body ground Power switch signal Power switch ON (IG) 10 to 14 V
      E01 (E83-105) - Body ground W-B - Body ground Ground Always Below 1 Ω
      E02 (E83-106) - Body ground W-B - Body ground Ground Always Below 1 Ω
      E03 (E83-107) - Body ground W-B - Body ground Ground Always Below 1 Ω
      E04 (E83-23) - Body ground W-B - Body ground Ground Always Below 1 Ω
      E05 (E83-46) - Body ground W-B - Body ground Ground Always Below 1 Ω
      E1 (E83-104) - Body ground BR - Body ground Ground Always Below 1 Ω
      EC (A53-32) - Body ground W-B - Body ground Ground Always Below 1 Ω
      ME01 (E83-43) - Body ground 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 A53 and E83 ECM connectors.
    4. Measure the voltage of the connectors.
      TERMINALS REFERENCE CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      KSW (A53-28) - E1 (E83-104) L - BR Power switch signal (input) Power switch OFF 4 to 6 V
      KSW (A53-28) - E1 (E83-104) L-BR Power switch signal (input) Power switch ON (ACC) 10 to 14 V
      KSW (A53-28) - E1 (E83-104) L-BR Power switch signal (input) Power switch ON (IG) Below 1.5 V

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

  5. CHECK HV CONTROL ECU 
    Fig 9: Identifying Terminals Of HV Control ECU
    G05814558Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Measure the voltage of the connectors.
      TERMINALS REFERENCE CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      BATT (A54-20) - E1 (A54-18) L-W-B Battery power supply Always 10 to 14 V
      +B (A54-46) - E1 (A54-18) B-R - W-B Ignition power supply Power switch ON (IG) 10 to 14 V
      RDY (A54-117) - E1 (A54-18) W-L - W-B READY signal Power switch ON (IG) or ON (READY) Pulse generation (see WAVEFORM REFERENCE waveform)
      ST2 (A54-22) - E1 (A54-18) Y-B - W-B Starter actuation request signal Power switch ON (IG) 0 to 1.5 V

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

    2. Using an oscilloscope, check the signal waveform of the ECU.

      Waveform (Reference): 

      WAVEFORM REFERENCE

      Item Content
      Symbols (Terminal No.) RDY (A54-117) - E1 (A54-18)
      Tool Setting 10V/DIV., 10 msec./DIV.
      Vehicle Condition Power switch ON (IG) or ON (READY)
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