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Terminals Of Ecu

WARNING: This page is about a different car, the 2012 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK CERTIFICATION ECU 
    Fig 1: Certification ECU Connector Terminal Identification
    GTY187592Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the D39 and D40 ECU connectors.
    2. Measure the resistance and voltage of each terminal of the wire harness side connector.

      Standard

      Symbols (Terminals No.) Wiring Color Terminal Description Condition Specified Condition
      +B1 (D39-1) - Body ground R - Body ground +B power supply Always 10 to 14 V
      TSW1 (D39-3) - Body ground G - Body ground Trigger switch (Lock switch) signal Front lock switch LH not pushed → Pushed 10 kΩ or higher → Below 1 Ω
      TSW2 (D39-4) - Body ground GR - Body ground Trigger switch (Lock switch) signal Front lock switch RH not pushed → Pushed 10 kΩ or higher → Below 1 Ω
      TSW5 (D39-7) - Body ground G - Body ground Luggage compartment open switch signal Luggage compartment open switch not pushed → Pushed 10 kΩ or higher → Below 1 Ω
      LIN (D39-10) - Body ground L - Body ground LIN line Always 10 kΩ or higher
      E (D39-17) - Body ground W - Body ground Ground Always Below 1 Ω
      IG (D39-18) - Body ground Y - Body ground Ignition power supply Engine switch OFF → ON (IG) Below 1 V → 10 to 14 V
      ACC (D39-19) - Body ground SB - Body ground ACC power supply Engine switch OFF → ON (ACC) Below 1 V → 10 to 14 V
      TSW3 (D40-25) - Body ground Y - Body ground Trigger switch (Lock switch) signal Rear lock switch LH not pushed → Pushed 10 kΩ or higher → Below 1 Ω
      TSW4 (D40-26) - Body ground GR - Body ground Trigger switch (Lock switch) signal Rear lock switch RH not pushed → Pushed 10 kΩ or higher → Below 1 Ω
      MPX1 (D39-27) - Body ground R - Body ground MPX line Always 10 kΩ or higher
      MPX2 (D39-28) - Body ground V - Body ground MPX line Always 10 kΩ or higher
      AGND (D39-40) - Body ground SB - 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 D39 and D40 ECU connectors.
    4. Measure the voltage and frequency of each terminal of the connector.

      Standard

      Symbols (Terminals No.) Wiring Color Terminal Description Condition Specified Condition
      SEL1 (D39-5) - Body ground P - Body ground Outside handle antenna signal Move the key more than 5 m (16.4 ft) away from the front door LH. → Bring it to the outside handle. 10 to 14 V → Below 1 V
      SEL2 (D39-6) - Body ground L - Body ground Outside handle antenna signal Move the key more than 5 m (16.4 ft) away from the front door RH. → Bring it to the outside handle. 10 to 14 V → Below 1 V
      TXCT (D39-8) - Body ground GR - Body ground Transponder key amplifier output signal Key is not in the cabin. → Have the key outside the cabin and open the driver's door. Below 1 V → Pulse generation
      (see waveform 1 found in Fig 2)
      CODE (D39-9) - Body ground W - Body ground Transponder key amplifier communication signal Key is not in the cabin. → Have the key outside the cabin and open the driver's door. Below 1 V → Pulse generation
      (see waveform 2 found in Fig 3)
      CG5B (D39-12) - CLG5 (D39-11) W - B Cabin oscillator front signal Engine switch OFF → ON (IG) after more than 30 seconds of driver door's opening or closing. Some Hz → 0 Hz
      CG6B (D39-14) - CLG6 (D39-13) SB - R Cabin oscillator rear signal Engine switch OFF → Close all the doors with the key in the cabin and turn the lock switch on. Some Hz → 0 Hz
      CG7B (D39-16) - CLG7 (D39-15) BE - G Luggage compartment oscillator inner signal Engine switch OFF → Turn the luggage compartment lock switch on with all the doors unlocked. Some Hz → 0 Hz
      SEN1 (D39-22) - Body ground BE - Body ground Outside handle antenna signal Front door LH outside handle is not held. → Front door LH outside handle is held. 10 to 14 V → Below 1 V
      SEN2 (D39-23) - Body ground B - Body ground Outside handle antenna signal Front door RH outside handle is not held. → Front door RH outside handle is held. 10 to 14 V → Below 1 V
      RC0 (D39-29) - Body ground SB - Body ground Tuner power source Engine switch OFF, all doors closed and key switch OFF → ON Below 1 V → 4.6 to 5.4 V
      VC5 (D39-30) - Body ground BE - Body ground Transponder key amplifier power supply Key is not in the vehicle. → Have the key outside the cabin and open the driver's door. Below 1 V → 4.6 to 5.4 V
      CG8B (D39-32) - CLG8 (D39-31) P - LG Luggage compartment oscillator outer signal Engine switch OFF → Turn the luggage compartment lock switch on with all the doors unlocked. Some Hz → 0 Hz
      CLG1 (D39-33) - Body ground SB - Body ground Door oscillator output signal All doors closed (locked), engine switch OFF → ON (IG) Some Hz → 0 Hz
      CG1B (D39-34) - Body ground V - Body ground Door oscillator output signal All doors closed (locked), engine switch OFF → ON (IG) Some Hz → 0 Hz
      CLG2 (D39-35) - Body ground LG - Body ground Door oscillator output signal All doors closed (locked), engine switch OFF → ON (IG) Some Hz → 0 Hz
      CG2B (D39-36) - Body ground BR - Body ground Door oscillator output signal All doors closed (locked), engine switch OFF → ON (IG) Some Hz → 0 Hz
      RDA (D39-38) - Body ground Y - Body ground Tuner input signal Engine switch OFF, all doors closed and transmitter switch not pressed. 11 to 14 V pulse generation at regular intervals
      Engine switch OFF, all doors closed and transmitter switch pressed. Pulse generation
      RSSI (D39-39) - Body ground R - Body ground Tuner radio wave detection signal Engine switch OFF, all doors closed, the key is not in the action area. → The key is in the action area. 10 to 14 V → Below 1 V
      SEL3 (D40-1) - Body ground L - Body ground Outside handle antenna signal Move the key more than 5 m (16.4 ft) away from the rear door LH. → Bring it to the outside handle. 10 to 14 V → Below 1 V
      SEL4 (D40-2) - Body ground B - Body ground Outside handle antenna signal Move the key more than 5 m (16.4 ft) away from the rear door RH. → Bring it to the outside handle. 10 to 14 V → Below 1 V
      CLG3 (D40-8) - Body ground W - Body ground Door oscillator output signal All doors closed (locked), engine switch OFF → ON (IG) Some Hz → 0 Hz
      CG3B (D40-9) - Body ground B - Body ground Door oscillator output signal All doors closed (locked), engine switch OFF → ON (IG) Some Hz → 0 Hz
      CLG4 (D40-10) - Body ground V - Body ground Door oscillator output signal All doors closed (locked), engine switch OFF → ON (IG) Some Hz → 0 Hz
      CG4B (D40-11) - Body ground P - Body ground Door oscillator output signal All doors closed (locked), engine switch OFF → ON (IG) Some Hz → 0 Hz
      SEN4 (D40-27) - Body ground BE - Body ground Outside handle antenna signal Rear door RH outside handle is not held. → Rear door RH outside handle is held. 10 to 14 V → Below 1 V
      SEN3 (D40-28) - Body ground BR - Body ground Outside handle antenna signal Rear door LH outside handle is not held. → Rear door LH outside handle is held. 10 to 14 V → Below 1 V

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

    5. Inspect using oscilloscope.
      Fig 2: Identifying Waveform 1
      GTY195407Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      WAVEFORM 1 (REFERENCE):

      Terminal TXCT - Body ground
      Tool Setting 2 V/DIV, 10 ms/DIV
      Condition The key is not in the cabin.
    6. Inspect using oscilloscope.
      Fig 3: Identifying Waveform 2
      GTY195409Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      WAVEFORM 2 (REFERENCE):

      Terminal CODE - Body ground
      Tool Setting 2 V/DIV, 20 ms/DIV
      Condition The key is not in the cabin.
  2. CHECK ID CODE BOX 
    Fig 4: Check ID Code Box Connector Terminal Identification
    GTY173902Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the D29 ID code box connector.
    2. Measure the resistance of each terminal of the wire harness side connector.

      Resistance

      Symbols (Terminals No.) Wiring Color Terminal Description Condition Specified Condition
      LIN (D29-3) - Body ground LG - Body ground LIN line Always 10 kΩ or higher
      GND (D29-8) - Body ground W-B - Body ground Ground Always Below 1 Ω
      MPXB (D29-1) - GND (D29-8) W - W-B Power supply Always 10 to 14 V

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

    3. Reconnect the D29 ECU connector.
    4. Measure the voltage of each terminal of the connector.

      Standard

      Symbols (Terminals No.) Wiring Color Terminal Description Condition Specified Condition
      EFIO (D29-6) - Body ground BR - Body ground ECM output signal Engine switch ON (IG) Pulse generation
      (see waveform 1 found in Fig 5)
      EFII (D29-5) - Body ground L - Body ground ECM input signal Within 3 seconds after starter operates and initial combustion occurs, or within 3 seconds after engine switch first turned ON (IG) after battery disconnected and connected. Pulse generation
      (see waveform 2 found in Fig 6)

      If the result is not as specified, the ID code box may have a malfunction.

    5. Inspect using oscilloscope.
      Fig 5: Identifying Waveform 1
      GTY195406Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      WAVEFORM 1 (REFERENCE):

      Terminal EFIO - Body ground
      Tool Setting 10 V/DIV, 100 ms/DIV
      Condition Engine switch ON (IG)
    6. Inspect using oscilloscope.
      Fig 6: Identifying Waveform 2
      GTY123956Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      WAVEFORM 2 (REFERENCE):

      Terminal EFII - Body ground
      Tool Setting 5 V/DIV., 500 ms/DIV.
      Condition Within 3 seconds after starter operates and initial combustion occurs, or within 3 seconds after engine switch first turned on (IG) after battery disconnected and connected.
  3. CHECK POWER SOURCE CONTROL ECU 
    Fig 7: Power Source Control ECU Connector Terminal Identification
    GTY206678Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the D44 ECU connector.
    2. Measure the resistance of each terminal of the wire harness side connector.

      Resistance

      Symbols (Terminals No.) Wiring Color Terminal Description Condition Specified Condition
      MPX1 (D44-7) - Body ground V - Body ground MPX line Always 10 kΩ or higher
      MPX2 (D44-24) - Body ground LG - Body ground MPX line Always 10 kΩ or higher
      LIN1 (D44-30) - Body ground BR - 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 D44 ECU connector.
    4. Measure the voltage and frequency of each terminal of the connector.

      Voltage

      Symbols (Terminals No.) Wiring Color Terminal Description Condition Specified Condition
      SLR+ (D44-32) - GND2 (D44-6) P - W-B Power source for steering lock actuator Steering lock motor operate → not operate Below 1 V → 10 to 14 V
      SLP (D44-26) - GND2 (D44-6) BE - W-B Steering lock actuator UNLOCK position signal Steering is locked → released Below 1 V → 10 to 14 V
      SPD (D44-19) - GND2 (D44-6) W - W-B Vehicle speed signal Engine switch ON (IG), Rotate driving wheel slowly Pulse generation
      TACH (D44-2) - Body ground L - Body ground Engine revolution speed signal Idling Pulse generation
      P (D44-5) - Body ground P - Body ground Shift lock signal Shift lever except P position Below 1.5 V
      CTSW (D44-31) - Body ground BE - Body ground Starter assist signal Cranking Below 1.5 V
      STSW (D44-39) - Body ground R - Body ground Starter request signal Brake pedal depressed, Shift lever P or N position, Engine switch ON (ACC, IG, START) 10 to 14 V
      STR1 (D44-17) - GND2 (D44-6) B - W-B Park / neutral position switch Shift lever P or N position, Engine switch START 10 to 14 V
      STR2 (D44-15) - GND2 (D44-6) SB - W-B Starter signal Shift lever P or N position, Engine switch START 10 to 14 V
      INDS (D44-4) - Body ground Y - Body ground Vehicle condition signal Brake pedal depressed, Shift lever P or N position, Engine switch ON (ACC, IG, START) 10 to 14 V
      INDW (D44-13) - Body ground GR - Body ground Warning signal Smart key system malfunction Pulse generation
      SWIL (D44-36) - Body ground G - Body ground Illumination signal Light control switch TAIL or HEAD 10 to 14 V

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

  4. CHECK STEERING LOCK ECU 
    1. Measure the voltage of the connectors.

      Voltage

      Symbols (Terminals No.) Wiring Color Terminal Description Condition Specified Condition
      SLP1 (D14-4) - GND (D14-1) BE - W-B Steering lock actuator UNLOCK position signal Steering is locked → released Below 1 V → 10 to 14 V
      IGE (D14-3) - GND (D14-1) P - W-B Power source for steering lock actuator Steering lock motor operate → not operate Below 1 V → 10 to 14 V

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

  5. CHECK ECM 
    Fig 8: ECM Connector Terminal Identification
    GTY190962Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the B50 ECM connector.
    2. Measure the resistance between each terminal of the wire harness side connectors and body ground.
      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      E01 (B50-22) - Body ground W-B - Body groubd 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 B50 ECM connector.
    4. Measure the voltage and resistance between each terminal of the wire harness side connectors and body ground.
      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      IMO (A55-10) - E01 (B50-22) G - W-B ID code box input signal Within 3 seconds after starter operates and initial combustion occurs, or within 3 seconds after engine switch first turned ON (IG) after battery disconnected and connected. Pulse generation
      (see waveform 1 found in Fig 9)
      IMI (A55-11) - E01 (B50-22) BE - W-B ID code box output signal Engine switch ON (IG) Pulse generation
      (see waveform 2 found in Fig 10)

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

    5. Inspect using an oscilloscope.
      1. Waveform 1 (Reference):
        Fig 9: Identifying Waveform 1
        GTY195406Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        Terminal IMI - GND
        Tool Setting 10 V/DIV., 500 ms/DIV.
        Condition Engine switch ON (IG)
      2. Waveform 2 (Reference)
        Fig 10: Identifying Waveform 2
        GTY123956Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
        Terminal IMO - GND
        Tool Setting 5 V/DIV., 500 ms/DIV.
        Condition Within 3 seconds after starter operates and initial combustion occurs, or within 3 seconds after engine switch first turned on (IG) after battery disconnected and connected.
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