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Microphone Circuit between Microphone and Navigation Receiver Assembly [11/2015 - ]: Procedure

  1. CHECK MICROPHONE (OPERATION CHECK) 
    1. Enter the "Microphone Check" screen.

      Refer to Check Microphone in Operation Check OPERATION CHECK [11/2015 - ] ).

      GTY451926Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. When a voice is input into the microphone, check that the microphone input level meter changes according to the input voice.

      OK

      Check result is normal.

    Result: 

    OK 

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE 

    Refer to PROBLEM SYMPTOMS TABLE [11/2015 - ] )

    Result: 

    NG 

    See step  2

  2. CHECK MODEL 
    1. Choose the model to be inspected.

      Result

      Result Proceed to
      w/o Sliding Roof A
      w/ Sliding Roof B

    Result: 

    B 

    See step  7

    Result: 

    A 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (NAVIGATION RECEIVER ASSEMBLY - AMPLIFIER MICROPHONE ASSEMBLY) 
    1. Disconnect the G78 navigation receiver assembly connector.
    2. Disconnect the Q5 amplifier microphone assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      G78-4 (MACC) - Q5-1 (MACC) Always Below 1 Ω
      G78-5 (MIN+) - Q5-2 (MCO+) Always Below 1 Ω
      G78-19 (MIN-) - Q5-3 (MCO-) Always Below 1 Ω
      G78-6 (SNS2) - Q5-4 (SNS2) Always Below 1 Ω
      G78-4 (MACC) - Body ground Always 10 kΩ or higher
      G78-5 (MIN+) - Body ground Always 10 kΩ or higher
      G78-19 (MIN-) - Body ground Always 10 kΩ or higher
      G78-18 (SGND) - Body ground Always 10 kΩ or higher
      G78-6 (SNS2) - Body ground Always 10 kΩ or higher

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  4

  4. INSPECT NAVIGATION RECEIVER ASSEMBLY 
    1. Measure the voltage according to the value(s) in the table below.
      GTY734418Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection Condition Specified Condition
      G78-4 (MACC) - Body ground Ignition switch ACC 4 to 6 V
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      G78-18 (SGND) - Body ground Always Below 1 Ω
      G78-19 (MIN-) - Body ground Always Below 1 Ω
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Navigation Receiver Assembly)

    Result: 

    NG 

    REPLACE NAVIGATION RECEIVER ASSEMBLY 

    Refer to REMOVAL [11/2015 - ] )

    Result: 

    OK 

    See step  5

  5. INSPECT AMPLIFIER MICROPHONE ASSEMBLY 
    1. Remove the amplifier microphone assembly (Refer to REMOVAL [11/2015 - ] ).
    2. Measure the resistance according to the value(s) in the table below.
      GTY702852Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition
      4 (SNS2) - 3 (MCO-) Always Below 1 Ω
      TEXT IN ILLUSTRATION

      *a Component without harness connected
      (Amplifier Microphone Assembly)

    Result: 

    NG 

    REPLACE AMPLIFIER MICROPHONE ASSEMBLY 

    Refer to REMOVAL [11/2015 - ] )

    Result: 

    OK 

    See step  6

  6. INSPECT AMPLIFIER MICROPHONE ASSEMBLY 
    1. Turn the ignition switch to ACC.
    2. Connect an oscilloscope to terminals 2 (MCO+) and 3 (MCO-) of the Q5 amplifier microphone assembly connector.
      GTY716073Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Check the waveform of the amplifier microphone assembly using the oscilloscope.

      Result

      Result Proceed to
      A waveform synchronized with the voice input to the amplifier microphone assembly is output. A
      A waveform synchronized with the voice input to the amplifier microphone assembly is not output. B
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Amplifier Microphone Assembly)

    Result: 

    A 

    END 

    Result: 

    B 

    REPLACE AMPLIFIER MICROPHONE ASSEMBLY 

    Refer to REMOVAL [11/2015 - ] )

  7. CHECK HARNESS AND CONNECTOR (NAVIGATION RECEIVER ASSEMBLY - MAP LIGHT ASSEMBLY (TELEPHONE MICROPHONE ASSEMBLY)) 
    1. Disconnect the G78 navigation receiver assembly connector.
    2. Disconnect the Q4 map light assembly (telephone microphone assembly) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      G78-4 (MACC) - Q4-4 (MACC) Always Below 1 Ω
      G78-5 (MIN+) - Q4-5 (MCO+) Always Below 1 Ω
      G78-19 (MIN-) - Q4-6 (MCO-) Always Below 1 Ω
      G78-6 (SNS2) - Q4-12 (SNS2) Always Below 1 Ω
      G78-4 (MACC) - Body ground Always 10 kΩ or higher
      G78-5 (MIN+) - Body ground Always 10 kΩ or higher
      G78-19 (MIN-) - Body ground Always 10 kΩ or higher
      G78-18 (SGND) - Body ground Always 10 kΩ or higher
      G78-6 (SNS2) - Body ground Always 10 kΩ or higher

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  8

  8. INSPECT NAVIGATION RECEIVER ASSEMBLY 
    1. Measure the voltage according to the value(s) in the table below.
      GTY734418Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Connection Condition Specified Condition
      G78-4 (MACC) - Body ground Ignition switch ACC 4 to 6 V
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      G78-18 (SGND) - Body ground Always Below 1 Ω
      G78-19 (MIN-) - Body ground Always Below 1 Ω
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Navigation Receiver Assembly)

    Result: 

    NG 

    REPLACE NAVIGATION RECEIVER ASSEMBLY 

    Refer to REMOVAL [11/2015 - ] )

    Result: 

    OK 

    See step  9

  9. INSPECT MAP LIGHT ASSEMBLY (TELEPHONE MICROPHONE ASSEMBLY) 
    1. Remove the map light assembly (telephone microphone assembly) (Refer to REMOVAL [11/2015 - ] ).
    2. Measure the resistance according to the value(s) in the table below.
      GTY712748Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition
      12 (SNS2) - 6 (MCO-) Always Below 1 Ω
      TEXT IN ILLUSTRATION

      *a Component without harness connected
      (Map Light Assembly (Telephone Microphone Assembly))

    Result: 

    NG 

    See step  11

    Result: 

    OK 

    See step  10

  10. INSPECT MAP LIGHT ASSEMBLY (TELEPHONE MICROPHONE ASSEMBLY) 
    1. Turn the ignition switch to ACC.
    2. Connect an oscilloscope to terminals 5 (MCO+) and 6 (MCO-) of the Q4 map light assembly (telephone microphone assembly) connector.
      GTY721049Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Check the waveform of the map light assembly (telephone microphone assembly) using the oscilloscope.

      Result

      Result Proceed to
      A waveform synchronized with the voice input to the map light assembly (telephone microphone assembly) is output. A
      A waveform synchronized with the voice input to the map light assembly (telephone microphone assembly) is not output. B
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (Map Light Assembly (Telephone Microphone Assembly))

    Result: 

    A 

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE 

    Refer to PROBLEM SYMPTOMS TABLE [11/2015 - ] )

    Result: 

    B 

    See step  11

  11. REPLACE TELEPHONE MICROPHONE ASSEMBLY 
    1. Replace the telephone microphone assembly with a new or known good one (Refer to REMOVAL [11/2015 - ] ).
    2. Check if the same malfunction recurs.

      Result

      Result Proceed to
      Malfunction does not recur (returns to normal) A
      Malfunction recurs B

    Result: 

    A 

    END 

    Result: 

    B 

    REPLACE MAP LIGHT ASSEMBLY 

    Refer to REMOVAL [11/2015 - ] )

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