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Terminals Of Ecu

  1. CHECK CERTIFICATION ECU 
    Fig 1: Identifying P33 Connector Terminal Identification
    GTY119886Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the P33 ECU connector.
    2. Measure the voltage and resistance according to the value(s) in the table below.
      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      +B1 (P33-1) - Body ground L - Body ground +B power supply Always 10 to 14 V
      IG (P33-18) - Body ground B - Body ground Ignition power supply Engine switch off Below 1 V
      IG (P33-18) - Body ground B - Body ground Ignition power supply Engine switch on (IG) 10 to 14 V
      E (P33-17) - Body ground W-B - Body ground Ground Always Below 1 Ω
      ACC (P33-19) - Body ground BE - Body ground ACC power supply Engine switch off Below 1 V
      ACC (P33-19) - Body ground BE - Body ground ACC power supply Engine switch on (ACC) 10 to 14 V
      TSW1 (P33-3) - Body ground Y - Body ground Entry lock switch signal Front lock switch LH not pushed 10 KΩ or higher
      TSW1 (P33-3) - Body ground Y - Body ground Entry lock switch signal Front lock switch LH pushed Below 1 Ω
      TSW2 (P33-4) - Body ground BR - Body ground Entry lock switch signal Front lock switch RH not pushed 10 KΩ or higher
      TSW2 (P33-4) - Body ground BR - Body ground Entry lock switch signal Front lock switch RH pushed Below 1 Ω
      LIN (P33-10) - Body ground V - Body ground LIN line Always 10 kΩ or higher
      MPX1 (P33-27) - Body ground GR - Body ground MPX line Always 10 kΩ or higher
      MPX2 (P33-28) - Body ground GR - Body ground MPX line Always 10 kΩ or higher
      AGND (P33-40) - Body ground LG - Body ground Ground Always Below 1 Ω
      • If the result is not as specified, the wire harness side may have a malfunction.
    3. Reconnect the P33 ECU connector.
    4. Measure the voltage according to the value(s) in the table below.
      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      CLG1 (P33-33) - CG1B (P33-34) R - BR Door electrical key oscillator (front LH) sensor signal All doors closed, all doors locked and engine switch off Alternating between 5 V and below 1 V
      CLG1 (P33-33) - CG1B (P33-34) R - BR Door electrical key oscillator (front LH) sensor signal Door unlocked or door open Below 1 V
      SEN1 (P33-22) - E (P33-17) G - W-B Touch sensor detection signal Outside door handle touched Below 1 V
      SEN1 (P33-22) - E (P33-17) G - W-B Touch sensor detection signal Outside door handle not touched 10 to 14 V
      SEL1 (P33-5) - E (P33-17) W - W-B Touch sensor activation control signal Move the key more than 5 m (16.4 ft) away from the front door LH 10 to 14 V
      SEL1 (P33-5) - E (P33-17) W - W-B Touch sensor activation control signal Bring it to the outside handle Below 1 V
      CLG2 (P33-35) - CG2B (P33-36) G - P Door electrical key oscillator (front RH) sensor signal All doors closed, all doors locked and engine switch off Alternating between 5 V and below 1 V
      CLG2 (P33-35) - CG2B (P33-36) G - P Door electrical key oscillator (front RH) sensor signal Door unlocked or door open Below 1 V
      SEN2 (P33-23) - E (P33-17) W - W-B Touch sensor detection signal Outside door handle touched Below 1 V
      SEN2 (P33-23) - E (P33-17) W - W-B Touch sensor detection signal Outside door handle not touched 10 to 14 V
      SEL2 (P33-6) - E (P33-17) B - W-B Touch sensor activation control signal Move the key more than 5 m (16.4 ft) away from the front door RH 10 to 14 V
      SEL2 (P33-6) - E (P33-17) B - W-B Touch sensor activation control signal Bring it to the outside handle Below 1 V
      CLG5 (P33-11) - CG5B (P33-12) Y - V Indoor electrical key oscillator (front) sensor signal 30 seconds after driver side door opened and closed, engine switch off Alternating between 5 V and below 1 V
      CLG5 (P33-11) - CG5B (P33-12) Y - V Indoor electrical key oscillator (front) sensor signal Within 30 seconds driver side door opened and closed, engine switch off Below 1 V
      CLG6 (P33-13) - CG6B (P33-14) LG - BE Indoor electrical key oscillator (rear) sensor signal 30 seconds after driver side door opened and closed, engine switch off Alternating between 5 V and below 1 V
      CLG6 (P33-13) - CG6B (P33-14) LG - BE Indoor electrical key oscillator (rear) sensor signal Within 30 seconds driver side door opened and closed, engine switch off Below 1 V
      CLG7 (P33-15) - CG7B (P33-16) SB - P Luggage electrical key oscillator (inner) sensor signal Luggage compartment door opening switch OFF Alternating between 5 V and below 1 V
      CLG7 (P33-15) - CG7B (P33-16) SB - P Luggage electrical key oscillator (inner) sensor signal Luggage compartment door opening switch ON Below 1 V
      CLG8 (P33-31) - CG8B (P33-32) B - W Luggage electrical key oscillator (outer) sensor signal Luggage compartment door opening switch OFF Alternating between 5 V and below 1 V
      CLG8 (P33-31) - CG8B (P33-32) B - W Luggage electrical key oscillator (outer) sensor signal Luggage compartment door opening switch ON Below 1 V
      RC0 (P33-29) - E (P33-17) LG - W-B Entry door control receiver power source Engine switch off, all doors closed and electrical key switch on. 4.6 to 5.4 V
      RC0 (P33-29) - E (P33-17) LG - W-B Entry door control receiver power source Engine switch off, all doors closed and electrical key switch off. Below 1 V
      RSSI (P33-39) - E (P33-17) Y - W-B Entry door control receiver electric wave existence signal Engine switch off, all doors closed, the electrical key is not in the action area. 10 to 14 V
      RSSI (P33-39) - E (P33-17) Y - W-B Entry door control receiver electric wave existence signal Engine switch off, all doors closed, the electrical key is in the action area. Below 1 V
      VC5 (P33-30) - Body ground L - Body ground Transponder key amplifier power supply Electrical key is not in the vehicle. Below 1 V
      VC5 (P33-30) - Body ground L - Body ground Transponder key amplifier power supply Have the electrical key outside the cabin and open the driver's door. 4.6 to 5.4 V
      TXCT (P33-8) - Body ground G - Body ground Transponder key amplifier output signal Electrical key is not in the cabin. Below 1 V
      TXCT (P33-8) - Body ground G - Body ground Transponder key amplifier output signal Have the electrical key outside the cabin and open the driver's door. Pulse generation (see waveform 1)
      CODE (P33-9) - Body ground GR - Body ground Transponder key amplifier communication signal Electrical key is not in the cabin. Below 1 V
      CODE (P33-9) - Body ground GR - Body ground Transponder key amplifier communication signal Have the electrical key outside the cabin and open the driver's door. Pulse generation (see waveform 2)

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

    5. Inspect using an oscilloscope.
      Fig 2: Waveform 1
      GTY121524Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      WAVEFORM 1 (REFERENCE):

      Terminal TXCT - Body ground
      Tool Setting 2 V/DIV, 10 ms/DIV
      Condition The electrical key is not in the cabin.
    6. Inspect using an oscilloscope.
      Fig 3: Waveform 2
      GTY126654Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      WAVEFORM 2 (REFERENCE):

      Terminal CODE - Body ground
      Tool Setting 2 V/DIV, 20 ms/DIV
      Condition The electrical key is not in the cabin.
  2. MAIN BODY ECU LH (COWL SIDE JUNCTION BLOCK LH) 
    1. Measure the voltage according to the value(s) in the table below.
      Fig 4: Identifying Main Body ECU LH (Cowl Side Junction Block LH)
      GTY119542Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      LPSW (Q3-13) - Body ground BR - Body ground Luggage compartment opener switch signal Luggage compartment opener switch OFF 10 to 14 V
      LPSW (Q3-13) - Body ground BR - Body ground Luggage compartment opener switch signal Luggage compartment opener switch ON Below 1 V

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

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