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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 RADIO RECEIVER ASSEMBLY 
    Fig 1: Identifying Radio Receiver Assembly ECU R3 Receiver Connector
    G05293049Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the R3 receiver connector.
    2. Measure the voltage and resistance of the wire harness side connector.
      ECU 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
      +B (R3-1) - GND (R3-20) W-R - W-B Battery power supply Always 10 to 14 V
      ACC (R3-11) - GND (R3-20) GR - W-B ACC power supply Ignition switch OFF 0 V
      ACC (R3-11) - GND (R3-20) GR - W-B ACC power supply Ignition switch ON 10 to 14 V
      ILL+ (R3-2) - Body ground G - Body ground Illumination signal Body ground light control switch 10 to 14 V
      ILL-(R3-12)-Body ground W-G - Body ground Illumination signal light control switch OFF 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 the connector.
      ECU CONNECTOR TERMINALS REFERENCE CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      DOS1 (R1-2) - GND (R3-20) L - W-B Audio door control signal Audio door control switch pushed Below 1 V
      TX+ (R3-5) - GND (R3-20) LG - W-B AVC-LAN communication signal Ignition switch ACC 2 to 3 V
      TX- (R3-15) - GND (R3-20) G-R - W-B AVC-LAN communication signal Ignition switch ACC 2 to 3 V
      MUTE (R3-7) - GND (R3-20) L-W - W-B Mute signal Audio system is sounding Above 3.5 V
      MUTE (R3-7) - GND (R3-20) L-W - W-B Mute signal Changing modes Below 1 V
      R+ (R3-8) - GND (R3-20) B - W-B Sound signal (Right) Audio system is playing Waveform synchronized with sound is output
      R- (R3-18) - GND (R3-20) W - W-B Sound signal (Right) Audio system is playing Waveform synchronized with sound is output
      L+ (R3-9) - GND (R3-20) R - W-B Sound signal (Left) Audio system is playing Waveform synchronized with sound is output
      L- (R3-19) - GND (R3-20) G - W-B Sound signal (Left) Audio system is playing Waveform synchronized with sound is output
      SGND (R3-10) - Body ground Shielded - Body ground Shielded ground Always Below 1 Ω
      TXS+ (R1-3) - GND (R3-20) LG - W-B AVC-LAN communication signal Ignition switch ACC 2 to 3 V
      TXS- (R1-6) - GND (R3-20) P - W-B AVC-LAN communication signal Ignition switch ACC 2 to 3 V
      CMP+ (R3-4) - GND (R3-20)*1, *2 L - W-B Traffic message channel signal Ignition switch ACC Traffic message channel is output Waveform synchronized with sound is output
      CMP- (R3-14) - GND (R3-20)*1, *2 P - W-B Traffic message channel signal Ignition switch ACC Traffic message channel is output Waveform synchronized with sound is output
      ANTA (R1-1) - GND (R3-20) L-R - W-B Antenna control signal Changing between AM and FM 10 to 14 V
      ANTB (R1-4) - GND (R3-20) W-R - W-B Antenna control signal Changing between AM and FM 10 to 14 V
      ANT (R3-13) - GND (R3-20) B-R - W-B Antenna control signal Changing between AM and FM 10 to 14 V
      HINT:
      *1: w/ Navigation System
      *2: for Taiwan, South Korea

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

  2. CHECK STEREO COMPONENT AMPLIFIER ASSEMBLY 
    Fig 2: Identifying S22 And S23 Amplifier Connectors Terminals
    G05293050Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the S22 and S23 amplifier connectors.
    2. Measure the voltage and resistance of the connectors.
      ECU CONNECTOR 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
      E (S22-12) - 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 0 V
      ACC (S23-20) - GND (S22-13) GR - W-B ACC power supply Ignition switch ON 10 to 14 V

      If the result is not as specified, the wire harness side may have a malfunction.

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

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      FR+ (S22-1) - GND (S22-13) LG - W-B Sound signal (front right) Audio system is playing Waveform synchronized with sound is output
      FL+ (S22-2) - GND (S22-13) P - W-B Sound signal (front left) Audio system is playing Waveform synchronized with sound is output
      RR+ (S22-3) - GND (S22-13) R - W-B Sound signal (rear right) Audio system is playing Waveform synchronized with sound is output
      RL+ (S22-4) - GND (S22-13) B - W-B Sound signal (rear left) Audio system is playing Waveform synchronized with sound is output
      WF+ (S22-5) - GND (S22-13) L-R - W-B Sound signal (rear No. 2) Audio system is playing Waveform synchronized with sound is output
      WF- (S22-6) - GND (S22-13) R-L - W-B Sound signal (rear No. 2) Audio system is playing Waveform synchronized with sound is output
      FR- (S22-8) - GND (S22-13) L - W-B Sound signal (front right) Audio system is playing Waveform synchronized with sound is output
      FL- (S22-9) - GND (S22-13) V - W-B Sound signal (front left) Audio system is playing Waveform synchronized with sound is output
      RR- (S22-10) - GND (S22-13) W - W-B Sound signal (rear right) Audio system is playing Waveform synchronized with sound is output
      RL- (S22-11) - GND (S22-13) Y - W-B Sound signal (rear left) Audio system is playing Waveform synchronized with sound is output
      TFR+ (S23-1) - GND (S22-13) L-B - W-B Sound signal (front right) Audio system is playing Waveform synchronized with sound is output
      TFL+ (S23-2) - GND (S22-13) LG - W-B Sound signal (front left) Audio system is playing Waveform synchronized with sound is output
      TDX+ (S23-6) - GND (S22-13) LG - W-B AVC-LAN communication signal Ignition switch ACC 2 to 3 V
      MTX+ (S23-5) - GND (S22-13)* V - 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 Audio system is sounding Above 3.5 V
      N-MU (S23-9) - GND (S22-13)* W - W-B Mute signal Voice guidance is on Below 1 V
      R+(S23-11) - GND (S22-13) B - W-B Sound signal from radio receiver (right) Audio system is playing Waveform synchronized with sound is output
      L+ (S23-12) - GND (S22-13) R - W-B Sound signal from radio receiver (left) Audio system is playing Waveform synchronized with sound is output
      SPD (S23-13) - GND (S22-13) W-R - W-B Speed signal from combination meter Vehicle is driving Pulse generation
      TFR- (S23-14) - GND (S22-13) L-R - W-B Sound signal (front right) Audio system is playing Waveform synchronized with sound is output
      TFL- (S23-15) - GND (S22-13) L - W-B Sound signal (front left) Audio system is playing Waveform synchronized with sound is output
      MTX- (S23-18) - GND (S22-13)* P - W-B AVC-LAN communication signal Ignition switch ACC 2 to 3 V
      TDX- (S23-19) - GND (S22-13) G-R - W-B AVC-LAN communication signal Ignition switch ACC 2 to 3 V
      MUTE (S23-21) - GND (S22-13) L-W - W-B Mute signal from radio receiver Audio system is sounding Above 3.5 V
      MUTE (S23-21) - GND (S22-13) L-W - W-B Mute signal from radio receiver Changing modes Below 1 V
      R- (S23-23) - GND (S22-13) W - W-B Sound signal from radio receiver (right) Audio system is playing Waveform synchronized with sound is output
      L- (S23-24) - GND (S22-13) G - W-B Sound signal from radio receiver (left) Audio system is playing Waveform synchronized with sound is output
      HINT:
      *: w/ Navigation System

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

  3. CHECK STEERING PAD SWITCH MODULATOR 
    Fig 3: Identifying Steering Pad Switch Modulator Connector Terminals
    G05293051Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the switch connector.
    2. Measure the voltage and resistance of the wire harness side connector.
      STEERING PAD SWITCH MODULATOR CONNECTOR TERMINALS CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      +B (1)-Body ground B-O - Body ground Battery power supply Always 10 to 14 V
      ECC (4) - Body ground BR - Body ground Ground Always Below 1 Ω

      If the result is not as specified, the wire harness side may have a malfunction.

  4. CHECK AUDIO DOOR CONTROL SWITCH 
    Fig 4: Identifying A25 Audio Door Control Switch Connector Terminals
    G05293052Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the A25 switch connector.
    2. Measure the voltage and resistance of the wire harness side connector.
      AUDIO DOOR CONTROL SWITCH CONNECTOR TERMINALS CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      ACC (A25-4) - GND (A25-6) GR - W-B ACC power supply Ignition switch OFF 0 V
      ACC (A25-4) - GND (A25-6) GR - W-B ACC power supply Ignition switch ON 10 to 14 V
      GND (A25-6) - Body ground W-B - Body ground Ground Always Below 1 Ω
      +B (A25-10) - GND (A25-6) V - W-B Battery Always 10 to 14 V

      If the result is not as specified, the wire harness side may have a malfunction.

    3. Reconnect the A25 switch connector.
    4. Measure the voltage of the switch connector.
      TERMINALS REFERENCE CHART

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      DOS1 (A25-8) - GND (A25-6) L - W-B Audio door control switch Audio door open 0 V
      DOS1 (A25-8) - GND (A25-6) L - W-B Audio door control switch Audio door close 10 to 14 V

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

  5. CHECK GATEWAY ECU 
    Fig 5: Identifying G3 Gateway ECU Connector Terminals
    G05293053Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the G3 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
      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 ON 10 to 14 V
      ACC (G3-12) - GND (G3-24) GR - W-B ACC power supply Ignition switch ACC 10 to 14 V

      If the result is not as specified, the wire harness side may have a malfunction.

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

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      GTX+ (G3-6) - GND (G3-24) LG - W-B AVC-LAN communication signal Ignition switch ACC 2 to 3 V
      GTX- (G3-20) - GND (G3-24) P - W-B AVC-LAN communication signal Ignition switch ACC 2 to 3 V

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

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