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Terminals Of Ecu

  1. CHECK DISTANCE CONTROL ECU (CRUISE CONTROL ECU) 
    Fig 1: Identifying K13 Distance Control ECU (Cruise Control ECU) Connector Terminals
    G05306710Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the K13 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 (K13-1) - GND (K13-12) L - G Battery Always 10 to 14 V
      SGND (K13-10) - Body ground B - Body ground Ground Always Below 1 Ω
      GND (K13-12) - Body ground G - Body ground Ground Always Below 1 Ω
      IGB (K13-13) - GND (K13-12) R - G Power source supply Power switch OFF Below 1 V
      IGB (K13-13) - GND (K13-12) R-G Power source supply Power switch ON (IG) 10 to 14 V

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

    3. Reconnect the K13 ECU connector.
    4. Measure the voltage of the connector.
      TERMINALS SPECIFIED CONDITION

      Symbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition
      LRDD (K13-13) - SGND (K13-12) O - B Millimeter wave radar sensor input signal Power switch ON (IG) Pulse generation (see WAVEFORM 1 )
      LRRD (K13-23) - SGND (K13-12) LG - B Millimeter wave radar sensor output signal Power switch ON (IG) Pulse generation (see WAVEFORM 2 )
      MODE (K13-16) - GND (K13-12) W - G Steering pad switch signal (Distance control switch signal) Power switch ON (IG), steering pad switch signal ON 0 to 2 V
      MODE (K13-16) - GND (K13-12) W - G Steering pad switch signal (Distance control switch signal) Power switch ON (IG), steering pad switch signal OFF 9 to 16 V

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

    5. Using an oscilloscope, check waveform 1.

      Waveform 1 

      ITEM REFERENCE CHART

      Item Content
      Symbols (Terminal No.) LRDD (K13-13) - SGND (K13-12)
      Tool Setting 2V/DIV., 10 msec./DIV.
      Vehicle Condition Power switch ON (IG)

      HINT:

      As vehicle speed increases, the wavelength shortens.

      Fig 2: Identifying Oscilloscope Waveform 1
      G05306711Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    6. Using an oscilloscope, check waveform 2.

      Waveform 2 

      ITEM REFERENCE CHART

      Item Content
      Symbols (Terminal No.) LRRD (K13-23) - SGND (K13-12)
      Tool Setting 2 V/DIV., 5 msec./DIV.
      Vehicle Condition Power switch ON (IG)

      HINT:

      As vehicle speed increases, the wavelength shortens.

      Fig 3: Identifying Oscilloscope Waveform 2
      G05306712Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. CHECK HYBRID VEHICLE CONTROL ECU 
    Fig 4: Identifying A54 And E84 Hybrid Vehicle Control ECU Connector Terminals
    G05306676Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the A54 ECU 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 (A54-46) - Body ground B-R - Body ground +B power supply Power switch ON (IG) 10 to 14 V
      BATT (A54-20) - Body ground L - Body ground BATT power supply Always 10 to 14 V
      E1 (A54-18) - Body ground W-B - Body ground Body ground Always Below 1 Ω
      STP (A54-112) - Body ground R-B - Body ground Stop light signal Power switch ON (IG), brake pedal release Below 1 V
      STP (A54-112) - Body ground R-B - Body ground Stop light signal Power switch ON (IG), brake pedal depressed 10 to 14 V
      ST1- (A54-70) - Body ground G-W - Body ground Stop light signal Power switch ON (IG), brake pedal release 10 to 14 V
      ST1- (A54-70) - Body ground G-W - Body ground Stop light signal Power switch ON (IG), brake pedal depressed Below 1 V
      CCS (A54-26) - E1 (A54-18) L-B - W-B Cruise control main switch signal Cruise control main switch ON Below 1 Ω
      CCS (A54-26) - E1 (A54-18) L-B - W-B Cruise control main switch signal Cruise control main switch OFF 10 kΩ or higher
      CCS (A54-26) - E1 (A54-18) L-B - W-B Cruise control main switch signal SET/COAST switch hold ON 620 to 640 Ω
      CCS (A54-26) - E1 (A54-18) L-B - W-B Cruise control main switch signal RES/ACC switch hold ON 235 to 245 Ω
      CCS(A54-26) - E1(A54-18) L-B - W-B Cruise control main switch signal CANCEL switch hold ON 1,510 to 1,570 Ω
      CCHG (A54-32) - E1 (A54-18) R-L - W-B Distance control switch signal Power switch ON (IG), cruise control main switch ON, MODE switch ON Below 1 Ω
      CCHG (A54-32) - E1 (A54-18) R-L - W-B Distance control switch signal Power switch ON (IG), cruise control main switch ON, MODE switch OFF 10 kΩ or higher

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

  3. CHECK MILLIMETER WAVE RADAR SENSOR 
    Fig 5: Identifying B8 Millimeter Wave Radar Sensor Connector Terminals
    G05298665Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the B8 sensor connector.
    2. Measure the voltage and resistance of the wire harness side connector.
      TERMINALS SPECIFIED CONDITION

      Symbols (Terminals No.) Wiring Color Terminal Description Condition Specified Condition
      LGND (B8-1) - Body ground L-B - Body ground Ground (Distance signal) Power switch ON (IG) 10 to 14 V
      SGND (B8-2) - Body ground BR - Body ground Ground Always Below 1 Ω
      IGB (B8-5) - SGND (B8-2) R-BR Power source Power switch ON (IG) 10 to 14 V

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

    3. Reconnect the B8 sensor connector.
    4. Measure the voltage of the connector.
      TERMINALS REFERENCE CHART

      Symbols (Terminals No.) Wiring Color Terminal Description Condition Specified Condition
      LRDD (B8-3) - SGND (B8-2) G - BR Millimeter wave radar sensor output signal Power switch ON (IG) Pulse generation (see WAVEFORM 1 )
      LRRD (B8-4) - SGND (B8-2) LG - BR Millimeter wave radar sensor input signal Power switch ON (IG) Pulse generation (see WAVEFORM 2 )

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

    5. Using an oscilloscope, check waveform 1.

      Waveform 1 

      WAVEFORM REFERENCE CHART

      Item Content
      Symbols (Terminal No.) LRDD (B8-3) - SGND (B8-2)
      Tool Setting 2V/DIV., 10 msec./DIV.
      Vehicle Condition Power switch ON (IG)

      HINT:

      As vehicle speed increases, the wavelength shortens.

      Fig 6: Identifying Oscilloscope Waveform 1
      G05306711Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    6. Using an oscilloscope, check waveform 2.

      Waveform 2 

      WAVEFORM REFERENCE CHART

      Item Content
      Symbols (Terminal No.) LRRD (B8-4) - SGND (B8-2)
      Tool Setting 2 V/DIV., 5 msec./DIV.
      Vehicle Condition Power switch ON (IG)

      HINT:

      As vehicle speed increases, the wavelength shortens.

      Fig 7: Identifying Oscilloscope Waveform 2
      G05306712Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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