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Inspection Procedure

  1. CHECK DISPLAY AND NAVIGATION MODULE DISPLAY OR MULTI-DISPLAY 
    1. Check the waveform of the microphone using an oscilloscope.
      Fig 1: Identifying Display And Navigation Module Display Or Multi-Display Connectors Terminals
      G05762925Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      F27-11 (MIN+) - F27-10 (MIN-) Engine switch on (ACC) and "Voice" switch of steering pad switch pressed Waveform that matches sound spoken into microphone is output.

      Result 

      RESULT REFERENCE

      Result Proceed to
      OK (w/ Navigation System) A
      OK (w/o Navigation System) B
      NG C

    B: REPLACE MULTI-DISPLAY ASSEMBLY  (See REMOVAL  )

    C: Go to step 2 

    A: REPLACE DISPLAY AND NAVIGATION MODULE DISPLAY  (See REMOVAL )

  2. CHECK LEXUS LINK SYSTEM 
    1. Check if the vehicle is equipped with the LEXUS link system.

      Result 

      RESULT REFERENCE

      Result Proceed to
      w/o LEXUS Link System A
      w/ LEXUS Link System B

    B:  Go to step  6

    A: Go to next Step 

  3. CHECK HARNESS AND CONNECTOR (OVERHEAD JUNCTION BLOCK - MULTI-DISPLAY) 
    1. Disconnect the R7 overhead junction block connector.
    2. Disconnect the F27 display connector.
    3. Measure the resistance according to the value (s) in the table below.

      Standard Resistance 

      STANDARD RESISTANCE

      Tester Connection Condition Specified Condition
      F27-9 (MACC) - R7-22 (ACC) Always Below 1 Ω
      F27-11 (MIN+) - R7-21 (MI1+) Always Below 1 Ω
      F27-10 (MIN-) - R7-20 (MIC-) Always Below 1 Ω
      F27-9 (MACC) - Body ground Always 10 kΩ or higher
      F27-11 (MIN+) - Body ground Always 10 kΩ or higher
      F27-10 (MIN-) - Body ground Always 10 kΩ or higher
      4. Fig 2: Identifying R7 Overhead Junction Block Connector And F27 Display Connector Terminals
      G05762926Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next Step 

  4. CHECK MULTI-DISPLAY (MACC VOLTAGE) 
    1. Reconnect the F27 display connector.
    2. Measure the voltage according to the value (s) in the table below.

      Standard Voltage 

      STANDARD VOLTAGE

      Tester Connection Switch Condition Specified Condition
      F27-9 (MACC) - Body ground Engine switch on (ACC) 4 to 6V
      Fig 3: Identifying F27 Display Connector Terminals
      G05762925Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Result 

      RESULT REFERENCE

      Result Proceed to
      OK A
      NG (w/ Navigation System) B
      NG (w/o Navigation System) C

    B: REPLACE DISPLAY AND NAVIGATION MODULE DISPLAY  (See REMOVAL )

    C: REPLACE MULTI-DISPLAY ASSEMBLY  (See REMOVAL  )

    A: Go to next Step 

  5. CHECK MICROPHONE ASSEMBLY 
    1. Remove the microphone from the overhead junction block (See REMOVAL  ).
    2. Measure the resistance according to the value (s) in the table below.

      Standard Resistance 

      STANDARD RESISTANCE

      Tester Connection Condition Specified Condition
      1 (MIC+) - 3 (MIC-) Always 1.9 to 2.2 kΩ
      3. Fig 4: Identifying Microphone Connectors Terminals
      G05762928Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE MICROPHONE ASSEMBLY  (See REMOVAL  )

    OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE  (See PROBLEM SYMPTOMS TABLE  )

  6. CHECK HARNESS AND CONNECTOR (TELEPHONE ECU - MULTI-DISPLAY AND OVERHEAD JUNCTION BLOCK) 
    1. Disconnect the P2 ECU connector.
    2. Disconnect the F27 display connector.
    3. Disconnect the R7 junction block connector.
    4. Measure the resistance according to the value (s) in the table below.

      Standard Resistance 

      STANDARD RESISTANCE

      Tester Connection Condition Specified Condition
      P2-17 (MCO+) - F27-11 (MIN+) Always Below 1 Ω
      P2-18 (MCO-) - F27-10 (MIN-) Always Below 1 Ω
      P2-7 (MCVD) - R7-22 (ACC) Always Below 1 Ω
      P2-8 (MC1+) - R7-21 (MI1+) Always Below 1 Ω
      P2-9 (MC1-) - R7-20 (MIC-) Always Below 1 Ω
      P2-17 (MCO+) - Body ground Always 10 kΩ or higher
      P2-18 (MCO-) - Body ground Always 10 kΩ or higher
      P2-19 (SGND) - Body ground Always 10 kΩ or higher
      P2-7 (MCVD) - Body ground Always 10 kΩ or higher
      P2-8 (MC1+) - Body ground Always 10 kΩ or higher
      P2-9 (MC1-) - Body ground Always 10 kΩ or higher
      5. Fig 5: Identifying P2 ECU Connector, F27 Display Connector And R7 Junction Block Connector Terminals
      G05762929Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next Step 

  7. CHECK TELEPHONE ECU ASSEMBLY (TACC VOLTAGE) 
    1. Reconnect the P2 ECU connector.
    2. Measure the voltage according to the value (s) in the table below.

      Standard Voltage 

      STANDARD VOLTAGE

      Tester Connection Condition Specified Condition
      P2-7 (MCVD) - Body ground Engine switch on (ACC) 4 to 6V
      3. Fig 6: Identifying P2 ECU Connector Terminals
      G05762930Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE TELEPHONE ECU ASSEMBLY  (See REMOVAL )

    OK: Go to next Step 

  8. CHECK MICROPHONE ASSEMBLY 
    1. Remove the microphone from the overhead junction block (See REMOVAL  ).
    2. Measure the resistance according to the value (s) in the table below.

      Standard Resistance 

      STANDARD RESISTANCE

      Tester Connection Condition Specified Condition
      1 (MIC+) - 3 (MIC-) Always 1.9 to 2.2 kΩ

    NG: REPLACE MICROPHONE ASSEMBLY  (See REMOVAL  )

    Fig 7: Identifying Microphone Connectors Terminals
    G04945663Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE  (See PROBLEM SYMPTOMS TABLE  )

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