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Inspection Procedure

WARNING: This page is about a different car, the 2008 Lexus LS 600hL. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK DISPLAY AND NAVIGATION ASSEMBLY (MULTI-DISPLAY) 
    Fig 1: Identifying L60 Connector Terminals
    G05783530Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Check the waveform of the microphone using an oscilloscope.

      Measurement condition 

      DISPLAY CONTENTS

      Item Content
      Terminal No (Symbols) L60-11 (MIN+) - L60-10 (MIN-)
      Tool Setting 0 2V/DIV, 0 2 μs/DIV
      Condition w/o LEXUS Link System Power switch ON (ACC) and steering pad switch's "Voice" switch pressed w/ LEXUS Link System Power switch ON (ACC) and overhead junction block's "PHONE" button pressed

      OK: Waveform that matches sound spoken into microphone is output. 

      Result 

      RESULT CHART

      Result Proceed to
      OK (w/ Navigation System [for HDD]) A
      OK (w/ Navigation System [for DVD]) B
      OK (w/o Navigation System) C
      NG D

    B: REPLACE MULTI-DISPLAY  (see REMOVAL )

    C: REPLACE MULTI-DISPLAY  (See REMOVAL  )

    D: Go to step 2 

    A: REPLACE DISPLAY AND NAVIGATION ASSEMBLY  (see REMOVAL )

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

      Result 

      RESULT CHART

      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 - DISPLAY AND NAVIGATION ASSEMBLY [MULTI-DISPLAY]) 
    1. Disconnect the X4 junction block connector.
    2. Disconnect the L60 display connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      L60-9 (MACC) - X4-22 (ACC) Always Below 1 Ω
      L60-11 (MIN+) - X4-21 (MI1+)
      L60-10 (MIN-) - X4-20 (MIC)
      L60-9 (MACC) - Body ground Always 10 kΩ or higher
      L60-11 (MIN+) - Body ground
      L60-10 (MIN-) - Body ground
      Fig 2: Identifying L60 And X4 Connector Terminals
      G05783531Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  4. CHECK DISPLAY AND NAVIGATION ASSEMBLY [MULTI-DISPLAY] (MACC VOLTAGE) 
    1. Reconnect the L60 display connector
    2. Measure the voltage according to the value(s) in the table below.

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Switch Condition Specified Condition
      L60-9 (MACC) - Body ground Power switch ON (ACC) 4 to 6 V
      Fig 3: Identifying L60 Display Connector Terminals
      G05783532Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Result 

      RESULT CHART

      Result Proceed to
      OK A
      NG (w/ Navigation System [for HDD]) B
      NG (w/ Navigation System [for DVD]) C
      NG (w/o Navigation System) D

    B: REPLACE DISPLAY AND NAVIGATION ASSEMBLY  (see REMOVAL )

    C: REPLACE MULTI-DISPLAY  (see REMOVAL )

    D: REPLACE MULTI-DISPLAY  (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 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      1 (MIC+) - 3 (MIC-) Always 1.9 to 2.2 kΩ
      Fig 4: Checking Microphone Assembly Connector
      G05783533Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE MICROPHONE ASSEMBLY  (See REMOVAL  )

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

  6. CHECK HARNESS AND CONNECTOR (MAYDAY ECU - DISPLAY AND NAVIGATION ASSEMBLY AND OVERHEAD JUNCTION BLOCK) 
    1. Disconnect the R24 ECU connector
    2. Disconnect the L60 display connector
    3. Disconnect the X4 block connector.
    4. Measure the resistance according to the value(s) in the table below.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      R24-17 (MCO+) - L60-11 (MIN+) Always Below 1 Ω
      R24-18 (MCO-) - L60-10 (MIN-)
      R24-7 (TACC) - X4-22 (ACC)
      R24-8 (MC1+) - X4-21 (MI1+)
      R24-9 (MC1-) - X4-20 (MIC)
      R24-17 (MCO+) - Body ground Always 10 kΩ or higher
      R24-18 (MCO-) - Body ground
      R24-7 (TACC) - Body ground
      R24-8 (MC1+) - Body ground
      R24-9 (MC1-) - Body ground
      Fig 5: Identifying L60, R24 And X4 Connector Terminals
      G05783534Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  7. CHECK MAYDAY ECU (TACC VOLTAGE) 
    1. Reconnect the R24 ECU connector
    2. Measure the voltage according to the value(s) in the table below

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Switch Condition Specified Condition
      R24-7 (TACC) - Body ground Power switch ON (ACC) 4 to 6 V
      Fig 6: Identifying R24 ECU Connector
      G05783535Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE MAYDAY ECU  (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 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      1 (MIC+) - 3 (MIC-) Always 1.9 to 2.2 kΩ
      Fig 7: Checking Microphone Assembly Connector
      G05783536Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE MICROPHONE ASSEMBLY  (see REMOVAL )

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

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