2008 Lexus SC 430FACTORY OEM SERVICE PROCEDURE

Terminals Of Ecu

WARNING: This page is about a different car, the 2007 Lexus SC 430. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK MULTI-DISPLAY ASSEMBLY 
    Fig 1: Identifying M5 And M6 Multi-Display Connectors Terminals
    G05293242Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the M5 and M6 multi-display connectors.
    2. Measure the resistance and voltage of the wire harness side connectors.
      TERMINALS REFERENCE CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      GND1 (M5-11) - Body ground W-B - Body ground Ground Always Below 1 Ω
      ST1 (M5-12) - GND1 (M5-11) R - W-B Starter signal Ignition switch OFF 0 V
      ST1 (M5-12) - GND1 (M5-11) R - W-B Starter signal Ignition switch START 10 to 14 V
      +B1 (M5-10) - GND1 (M5-11) O - W-B Battery power supply Always 10 to 14 V
      ACC (M5-20) - GND1 (M5-11) GR - W-B ACC power supply Ignition switch OFF OV
      ACC (M5-20) - GND1 (M5-11) GR - W-B ACC power supply Ignition switch ACC 10 to 14 V
      IG( M5-19) - GND1 (M5-11) R-L - W-B Ignition (ON) power supply Ignition switch OFF OV
      IG (M5-19) - GND1 (M5-11) R-L - W-B Ignition (ON) power supply Ignition switch ON 10 to 14 V
      SGND (M6-4) - Body ground W-B - Body ground Shielded 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 M5 and M6 multi-display connectors.
    4. Measure the resistance and voltage of the connectors.
      TERMINALS REFERENCE CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      SPD (M5-18) - GND1 (M5-11) W-R - W-B Vehicle speed signal Turn the wheel Alternating between 9 to 14 V and below 2 V
      PKB (M5-17) - GND1 (M5-11) R-B - W-B Parking brake signal Parking brake switch OFF 10 to 14 V
      PKB (M5-17) - GND1 (M5-11) R-B - W-B Parking brake signal Parking brake switch ON Below 1 V
      TC (M5-8) - GND1 (M5-11) P-B - W-B Diagnosis ON signal Ignition switch ON 10 to 14 V
      OPEN/CLOSE (M5-3) - GND1 (M5-11) P - W-B Multi-display door open / close operate signal Ignition switch ACC, multi-display OPEN switch pressed Below 1 V
      OPEN/CLOSE (M5-3) - GND1 (M5-11) P - W-B Multi-display door open / close operate signal Ignition switch ACC, multi-display CLOSE switch pressed 10 to 14 V
      TILT(M5-13) - GND1 (M5-11) O - W-B Multi-display door tilt operate signal Ignition switch ACC, multi-display TILT switch not pressed 10 to 14 V
      TILT(M5-13) - GND1 (M5-11) O - W-B Multi-display door tilt operate signal Ignition switch ACC, multi-display TILT switch pressed Below 1 V
      OPEN (M5-4) - GND1 (M5-11) LG - W-B Multi-display door condition signal Ignition switch ACC, multi-display door open Below 1 V
      CLOSE (M5-14) - GND1 (M5-11) LG-B - W-B Multi-display door condition signal Ignition switch ACC, multi-display door close Below 1 V
      GND1 (M5-11) - Body ground W-B - Body ground Ground Always Below 1 Ω
      TX+ (M5-6) - GND1 (M5-11) L-R - W-B AVC-LAN communication signal Ignition switch ACC 2 to 3 V
      TX- (M5-19) - GND1 (M5-11) R-W - W-B AVC-LAN communication signal Ignition switch ACC 2 to 3 V
      B (M6-22) - GND1 (M5-11) BR - W-B Display signal (blue) Navigation display ON Pulse generation
      G (M6-21) - GND1 (M5-11) W - W-B Display signal (green) Navigation display ON Pulse generation
      R (M6-20) - GND1 (M5-11) R - W-B Display signal (red) Navigation display ON Pulse generation
      SYNC (M6-23) - GND1 (M5-11) L - W-B Display signal (synchronize) Navigation display ON Pulse generation
      VR (M6-19) - GND1 (M5-11) Y - W-B Video return signal Always Below 1 Ω
      VG (M6-24) - GND1 (M5-11) Shielded - W-B Shielded ground Always Below 1 Ω
      MCO+ (M6-17) - GND1 (M5-11) R - W-B Microphone voice signal Sounds received by microphone Pulse generation
      MCO- (M6-18) - GND1 (M5-11) L - W-B Microphone voice signal Always Below 1 Ω
      SGND (M6-16) - GND1 (M5-11) Shielded - W-B Shielded ground Always Below 1 Ω
      IVO+ (M6-9) - GND1 (M5-11) W - W-B Telephone voice signal (Bluetooth) Sounds received by microphone Pulse generation
      IVO- (M6-10) - GND1 (M-11) B - W-B Telephone voice signal (Bluetooth) Always Below 1 Ω
      SLD (M6-8) - GND1 (M5-11) Shielded - W-B Shielded ground Always Below 1 Ω
      MACO (M6-7) - GND1 (M5-11) R - W-B Microphone ACC power Ignition switch ACC 8V
      MIN+ (M6-5) - GND1 (M5-11) LG - W-B Microphone signal Ignition switch ACC 5V
      MIN- (M6-6) - GND1 (M5-11) V - W-B Microphone signal Always Below 1 Ω
      TLSW (M6-2) - GND1 (M5-11) L - W-B Steering pad switch telephone signal Steering pad switch TELEPHONE switch is pushed Below 1 V
      TSW- (M6-3) - Body ground BR - Body ground Steering pad switch telephone signal Always Below 1 Ω

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

  2. CHECK NAVIGATION ECU 
    Fig 2: Identifying N3 And N7 ECU Connectors Terminals
    G05293243Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the N3 and N7 ECU connectors.
    2. Measure the resistance and voltage of the wire harness side connectors.
      TERMINALS REFERENCE CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      ACC (N3-18) - GND1 (N3-17) GR - W-B ACC power supply Ignition switch OFF OV
      ACC (N3-18) - GND1 (N3-17) GR - W-B ACC power supply Ignition switch ON 10 to 14 V
      +B (N3-9) - GND1 (N3-17) O - W-B Battery power supply Always 10 to 14 V
      GND1 (N3-17) - Body ground W-B - Body ground Ground Always Below 1 Ω
      SNSE (N7-7) - Body ground W-B - Body ground Shielded 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 N3 and N7 ECU connectors.
    4. Measure the resistance and voltage of the connectors.
      TERMINALS REFERENCE CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      AUO+ (N3-2) - GND1 (N3-17) L-O - W-B Navigation voice signal Voice guidance ON Waveform synchronized with voice is output
      AUO- (N3-11) - GND1 (N3-17) Y-G - W-B Navigation voice signal Voice guidance ON Waveform synchronized with voice is output
      MUT2 (N3-15) - GND1 (N3-17) W - W-B Mute signal Audio system playing, voice guidance ON Below 1 V
      MUT2 (N3-15) - GND1 (N3-17) W - W-B Mute signal Audio system playing, voice guidance OFF Approx. 3.5 V
      SPD (N3-5) - GND1 (N3-17) W-R - W-B Vehicle speed signal Turn the wheel Alternating between 9 to 14 V and below 2 V
      REV (N3-14) - GND1 (N3-17) Y-R - W-B Reverse signal Shift lever position R 10 to 14 V
      REV (N3-14) - GND1 (N3-17) Y-R - W-B Reverse signal Shift lever position not R Below 1 V
      RSG (N3-16) - GND1 (N3-17) Shielded - Body ground Shielded ground Always Below 1 Ω
      VOI+ (N3-12) - GND1 (N3-17) W - W-B Telephone voice signal (Bluetooth) Sounds received by microphone Pulse generation
      VOI- (N3-13) - GND1 (N3-17) B - W-B Telephone voice signal (Bluetooth) Sounds received by microphone Pulse generation
      B (N4-3) - GND1 (N3-17) BR - W-B Display signal (blue) Navigation display ON Pulse generation
      G (N4-7) - GND1 (N3-17) W - W-B Display signal (green) Navigation display ON Pulse generation
      R (N4-2) - GND1 (N3-17) R - W-B Display signal (red) Navigation display ON Pulse generation
      SYNC (N4-8) - GND1 (N3-17) L - W-B Display signal (synchronize) Navigation display ON Pulse generation
      VR (N4-1) - GND1 (N3-17) Y - W-B Video return signal Always Below 1 Ω
      VG (N4-6) - GND1 (N3-17) Shielded - W-B Shielded ground Always Below 1 Ω
      TX+ (N4-5) - GND1 (N3-17) V - W-B AVC-LAN communication signal Ignition switch ACC 2 to 3 V
      TX- (N4-10) - GND1 (N3-17) P - W-B AVC-LAN communication signal Ignition switch ACC 2 to 3 V
      MIC+ (N7-3) - GND1 (N3-17) R - W-B Microphone voice signal Sounds received by microphone Pulse generation
      MIC- (N7-5) - GND1 (N3-17) L - W-B Microphone voice signal Sounds received by microphone Pulse generation

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

  3. CHECK RADIO RECEIVER ASSEMBLY 
    Fig 3: Identifying R3 Receiver Connector Terminals
    G05293244Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the R3 receiver connector.
    2. Measure the resistance and voltage of the wire harness side connector.
      TERMINALS REFERENCE CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      GND (R3-20) - Body ground W-B - Body ground Ground Always Below 1 Ω
      ACC (R3-11) - GND(R3-20) GR - W-B ACC power supply Ignition switch OFF OV
      ACC (R3-11) - GND(R3-20) GR - W-B ACC power supply Ignition switch ACC 10 to 14 V
      +B (R3-1) - GND(R3-20) W-R - W-B Battery power supply Always Below 1 V

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

    3. Reconnect the R3 receiver connector.
    4. Measure the voltage of connectors.
      TERMINALS REFERENCE CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      ATX+ (R2-10) - GND(R3-20)*2 L-R - W-B ACV-LAN communication signal Ignition switch ACC 2 to 3 V
      ATX+ (R3-6) - GND (R3-20)*1 L-R - W-B ACV-LAN communication signal Ignition switch ACC 2 to 3 V
      ATX- (R2-9) - GND (R3-20)*2 R-W - W-B ACV-LAN communication signal Ignition switch ACC 2 to 3 V
      ATX- (R3-16) - GND(R3-20)*1 R-W - W-B ACV-LAN communication signal Ignition switch ACC 2 to 3 V
      TXS+ (R1-3) - GND(R3-20) LG - W-B ACV-LAN communication signal Ignition switch ACC 2 to 3 V
      TXS- (R1-6) - GND(R3-20) P - W-B ACV-LAN communication signal Ignition switch ACC 2 to 3 V
      HINT:
      *1: for Taiwan, South Korea
      *2: for Except Taiwan, South Korea

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

  4. CHECK STEREO COMPONENT AMPLIFIER ASSEMBLY 
    Fig 4: Identifying S22 And S23 Amplifier Connectors Terminals
    G05293245Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the S22 and S23 amplifier connectors.
    2. Measure the resistance and voltage of the harness side connectors.
      TERMINALS REFERENCE CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      GND (S22-13) - Body ground W-B - Body ground Ground Always Below 1 Ω
      B+ (S22-7) - GND (S22-13) W-R - W-B Battery power supply Always 10 to 14 V
      B+ (S22-16) - GND (S22-13) W-R - W-B Battery power supply Always 10 to 14 V
      ACC (S23-20) - GND (S22-13) GR - W-B ACC power supply Ignition switch OFF OV
      ACC (S23-20) - GND (S22-13) GR - W-B ACC power supply Ignition switch ACC 10 to 14 V

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

    3. Reconnect the S22 and S23 amplifier connectors.
    4. Measure the voltage of the connectors.
      TERMINALS REFERENCE CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      MTX+ (S23-5) - GND (S22-13) V - W-B AVC-LAN communication signal Ignition switch ACC 2 to 3 V
      MTX- (S23-18) - GND (S22-13) P - W-B AVC-LAN communication signal Ignition switch ACC 2 to 3 V
      N-MU (S23-9) - GND (S22-13) W - W-B Mute signal Voice guidance ON Below 1 V
      TFL- (S23-15) - GND (S22-13) L - W-B Audio sound signal Audio system is operating Waveform synchronized with sound is output
      TFL+ (S23-2) - GND (S22-13) LG - W-B Audio sound signal Audio system is operating Waveform synchronized with sound is output

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

  5. CHECK GATEWAY ECU 
    Fig 5: Identifying G3 ECU Connector Terminals
    G05293246Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the G3 ECU connector.
    2. Measure the resistance and voltage of the wire harness side connector.
      TERMINALS REFERENCE CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      GND (G3-24) - Body ground W-B - Body ground Ground Always Below 1 Ω
      BATT (G3-10) - GND (G3-24) B - W-B Battery power supply Always 10 to 14 V
      IG (G3-1) - GND (G3-24) V-W - W-B Ignition power supply Ignition switch OFF OV
      IG (G3-1) - GND (G3-24) V-W - W-B Ignition power supply Ignition switch ON 10 to 14 V
      ACC (G3-2) - GND (G3-24) GR - W-B ACC power supply Ignition switch OFF OV
      ACC (G3-2) - GND (G3-24) GR - W-B ACC power supply Ignition switch ACC 10 to 14 V

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

    3. Reconnect the G3 ECU connector.
    4. Measure the voltage of the connector.
      TERMINALS REFERENCE CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      GTX+ (G3-6) - Body ground LG - Body ground AVC-LAN communication signal Ignition switch ON 2 to 3 V
      GTX- (G3-21) - Body ground P - Body ground AVC-LAN communication signal Ignition switch ON 2 to 3 V

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

  6. CHECK NAVIGATION AMPLIFIER 
    Fig 6: Identifying N6 Amplifier Connector Terminals
    G05293247Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the N6 amplifier connector.
    2. Measure the resistance of the voltage wire harness side connector.
      TERMINALS REFERENCE CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      GND (N6-8) - Body ground W-B - Body ground Ground Always Below 1 Ω
      ACC (N6-12) - GND (N6-8) GR - W-B ACC power supply Ignition switch OFF OV
      ACC (N6-12) - GND (N6-8) GR - W-B ACC power supply Ignition switch ACC 10 to 14 V
      +B (N6-5) - GND (N6-8) W-R - W-B Battery 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 N6 amplifier connector.
    4. Measure the voltage of the connector.
      TERMINALS REFERENCE CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      SP+ (N6-1) - GND (N6-8) BR - W-B Navigation voice signal Voice guidance ON Waveform synchronized with voice is output
      SP- (N6-6) - GND (N6-8) G - W-B Navigation voice signal Voice guidance ON Waveform synchronized with voice is output
      AUI+ (N6-2) - GND (N6-8) LG - W-B Audio sound signal Audio system is operating Waveform synchronized with voice is output
      AUI- (N6-7) - GND (N6-8) L - W-B Audio sound signal Audio system is operating Waveform synchronized with voice is output
      NAV+ (N6-10) - GND (N6-8) L-O - W-B Navigation voice signal Voice guidance ON Waveform synchronized with voice is output
      NAV- (N6-9) - GND (N6-8) Y-G - W-B Navigation voice signal Voice guidance ON Waveform synchronized with voice is output
      NAVI (N6-4) - GND (N6-8) W - W-B Mute signal Audio system playing, Voice guidance ON Below 1 V
      NAVI (N6-4) - GND (N6-8) W - W-B Mute signal Audio system playing, Voice guidance OFF Approx. 3.5 V
      NAVO (N6-11) - GND (N6-8) W - W-B Mute signal Audio system playing, Voice guidance ON Below 1 V
      NAVO (N6-11) - GND (N6-8) W - W-B Mute signal Audio system playing, Voice guidance OFF Approx. 3.5 V

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

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