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Microphone Circuit [11/2017 - 09/2020]: Procedure

  1. CHECK MICROPHONE AND VOICE RECOGNITION (INPUT TO NAVIGATION ECU) 
    1. Enter the "Microphone Check" screen. Refer to Check Microphone (Input to navigation ECU) in Operation Check.

      Refer to OPERATION CHECK [11/2017 - 09/2020]

      GTY434237Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. When voice is input into the microphone, check that the microphone input level meter changes according to the input voice.

      OK

      Check results are normal.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE [11/2017 - 03/2019]  , or refer to  PROBLEM SYMPTOMS TABLE [03/2019 - 09/2020] 

    Result: 

    NG 

    See step  2

  2. CHECK MICROPHONE AND VOICE RECOGNITION (INPUT TO RADIO RECEIVER ASSEMBLY) 
    1. Enter the "Microphone Check" screen. Refer to Check Microphone (Input to radio receiver assembly) in Operation Check.

      Refer to OPERATION CHECK [11/2017 - 09/2020]

      GTY434237Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. When voice is input into the microphone, check that the microphone input level meter changes according to the input voice.

      OK

      Check results are normal.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  5

    Result: 

    OK 

    See step  3

  3. CHECK HARNESS AND CONNECTOR (RADIO RECEIVER ASSEMBLY - NAVIGATION ECU) 
    1. Disconnect the O148 radio receiver assembly connector.
    2. Disconnect the O150 navigation ECU connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      O148-25 (MCO+) - O150-13 (MIC+) Always Below 1 Ω
      O148-26 (MCO-) - O150-14 (MIC-) Always Below 1 Ω
      O148-25 (MCO+) or O150-13 (MIC+) - Body ground Always 10 kΩ or higher
      O148-26 (MCO-) or O150-14 (MIC-) - Body ground Always 10 kΩ or higher
      O148-24 (SGND) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  4

  4. INSPECT RADIO RECEIVER ASSEMBLY (OUTPUT TO NAVIGATION ECU) 
    1. Disconnect the O150 navigation ECU connector.
    2. Turn the engine switch on (ACC).
    3. Check the signal waveform according to the condition(s) in the table below.
      GTY827496Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Navigation ECU)
      Item Condition
      Measurement terminal O150-13 (MIC+) - O150-14 (MIC-)
      Tool setting 50 mV/DIV., 500 ms/DIV.
      Vehicle condition
      1. Turn the engine switch on (ACC).
      2. Sound is input to the telephone microphone assembly when the user is closer than 125 mm from the telephone microphone assembly sound holes in the roof headlining holder cover.

      OK

      The waveform is similar to that shown in the illustration.

      HINT: 

      The oscilloscope waveform shown in the illustration is an example for reference only.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE [11/2017 - 03/2019]  , or refer to  PROBLEM SYMPTOMS TABLE [03/2019 - 09/2020] 

    Result: 

    NG 

    REPLACE RADIO RECEIVER ASSEMBLY. Refer to  REMOVAL [11/2017 - 03/2019]  , or refer to  REMOVAL [03/2019 - ] 

  5. CHECK MODEL 
    1. Check the model to be inspected.

      Result

      Result Proceed to
      w/ Manual (SOS) Switch A
      w/o Manual (SOS) Switch B

    Result: 

    B 

    See step  12

    Result: 

    A 

    See step  6

  6. CHECK HARNESS AND CONNECTOR (RADIO RECEIVER ASSEMBLY - TELEPHONE MICROPHONE ASSEMBLY) 
    1. Disconnect the O147 radio receiver assembly connector.
    2. Disconnect the W14 telephone microphone assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      O147-25 (SNS2) - W14-3 (SNS2) Always Below 1 Ω
      O147-25 (SNS2) or W14-3 (SNS2) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  7

  7. CHECK HARNESS AND CONNECTOR (RADIO RECEIVER ASSEMBLY - DCM [TELEMATICS TRANSCEIVER]) 
    1. Disconnect the O147 radio receiver assembly connector.
    2. Disconnect the O65 DCM (telematics transceiver) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      O147-21 (MIN+) - O65-18 (MCO+) Always Below 1 Ω
      O147-22 (MIN-) - O65-19 (MCO-) Always Below 1 Ω
      O147-21 (MIN+) or O65-18 (MCO+) - Body ground Always 10 kΩ or higher
      O147-22 (MIN-) or O65-19 (MCO-) - Body ground Always 10 kΩ or higher
      O147-24 (SGND) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  8

  8. CHECK HARNESS AND CONNECTOR (DCM [TELEMATICS TRANSCEIVER] - TELEPHONE MICROPHONE ASSEMBLY) 
    1. Disconnect the O65 DCM (telematics transceiver) connector.
    2. Disconnect the W14 telephone microphone assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      O65-33 (MCVD) - W14-1 (MACC) Always Below 1 Ω
      O65-34 (MCI+) - W14-2 (MCO+) Always Below 1 Ω
      O65-35 (MCI-) - W14-4 (MCO-) Always Below 1 Ω
      O65-33 (MCVD) or W14-1 (MACC) - Body ground Always 10 kΩ or higher
      O65-34 (MCI+) or W14-2 (MCO+) - Body ground Always 10 kΩ or higher
      O65-35 (MCI-) or W14-4 (MCO-) - Body ground Always 10 kΩ or higher
      O65-32 (SGND) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  9

  9. CHECK DCM (TELEMATICS TRANSCEIVER) 
    1. Remove the DCM (telematics transceiver) with the connector(s) still connected.
      GTY801883Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (DCM [Telematics Transceiver])
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      O65-33 (MCVD) - Body ground Engine switch on (ACC) 4 to 6 V
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      O65-32 (SGND) - Body ground Always Below 1 Ω
      O65-35 (MCI-) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE DCM (TELEMATICS TRANSCEIVER). Refer to  REMOVAL [11/2017 - 09/2020] 

    Result: 

    OK 

    See step  10

  10. CHECK TELEPHONE MICROPHONE ASSEMBLY (OUTPUT TO DCM [TELEMATICS TRANSCEIVER]) 
    GTY825865Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Component with harness connected
    (Telephone Microphone Assembly)
    1. Check the output waveform.
      1. Remove the telephone microphone assembly with the connector(s) still connected.

        Refer to REMOVAL [11/2017 - ]

      2. Connect an oscilloscope to terminal W14-2 (MCO+) and W14-4 (MCO-).
      3. Turn the engine switch on (ACC).
      4. Sound is input to the telephone microphone assembly when the user is closer than 125 mm from the telephone microphone assembly sound holes in the roof headlining holder cover.
      5. Check the signal waveform according to the condition(s) in the table below.
        Item Condition
        Measurement terminal W14-2 (MCO+) - W14-4 (MCO-)
        Tool setting 50 mV/DIV., 500 ms/DIV.
        Vehicle condition
        1. Engine switch on (ACC)
        2. Sound is input to the telephone microphone assembly when the user is closer than 125 mm from the telephone microphone assembly sound holes in the roof headlining holder cover.

        OK

        The waveform is similar to that shown in the illustration.

        HINT: 

        The oscilloscope waveform shown in the illustration is an example for reference only.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE TELEPHONE MICROPHONE ASSEMBLY. Refer to  REMOVAL [11/2017 - ] 

    Result: 

    OK 

    See step  11

  11. CHECK DCM (TELEMATICS TRANSCEIVER) (OUTPUT TO RADIO RECEIVER ASSEMBLY) 
    GTY779241Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Component with harness connected
    (DCM [Telematics Transceiver])
    1. Check the output waveform.
      1. Remove the DCM (telematics transceiver) with the connector(s) still connected.

        Refer to REMOVAL [11/2017 - 09/2020]

      2. Connect an oscilloscope to terminal O65-18 (MCO+) and O65-19 (MCO-).
      3. Turn the engine switch on (ACC).
      4. Sound is input to the telephone microphone assembly when the user is closer than 125 mm from the telephone microphone assembly sound holes in the roof headlining holder cover.
      5. Check the signal waveform according to the condition(s) in the table below.
        Item Condition
        Measurement terminal O65-18 (MCO+) - O65-19 (MCO-)
        Tool setting 50 mV/DIV., 500 ms/DIV.
        Vehicle condition
        1. Engine switch on (ACC)
        2. Sound is input to the telephone microphone assembly when the user is closer than 125 mm from the telephone microphone assembly sound holes in the roof headlining holder cover.

        OK

        The waveform is similar to that shown in the illustration.

        HINT: 

        The oscilloscope waveform shown in the illustration is an example for reference only.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE RADIO RECEIVER ASSEMBLY. Refer to  REMOVAL [11/2017 - 03/2019]  , or refer to  REMOVAL [03/2019 - ] 

    Result: 

    NG 

    REPLACE DCM (TELEMATICS TRANSCEIVER). Refer to  REMOVAL [11/2017 - 09/2020] 

  12. CHECK HARNESS AND CONNECTOR (RADIO RECEIVER ASSEMBLY - TELEPHONE MICROPHONE ASSEMBLY) 
    1. Disconnect the O147 radio receiver assembly connector.
    2. Disconnect the W14 telephone microphone assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      O147-25 (SNS2) - W14-3 (SNS2) Always Below 1 Ω
      O147-23 (MACC) - W14-1 (MACC) Always Below 1 Ω
      O147-21 (MIN+) - W14-2 (MCO+) Always Below 1 Ω
      O147-22 (MIN-) - W14-4 (MCO-) Always Below 1 Ω
      O147-25 (SNS2) or W14-3 (SNS2) - Body ground Always 10 kΩ or higher
      O147-23 (MACC) or W14-1 (MACC) - Body ground Always 10 kΩ or higher
      O147-21 (MIN+) or W14-2 (MCO+) - Body ground Always 10 kΩ or higher
      O147-22 (MIN-) or W14-4 (MCO-) - Body ground Always 10 kΩ or higher
      O147-24 (SGND) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  13

  13. CHECK RADIO RECEIVER ASSEMBLY 
    1. Remove the radio receiver assembly with the connector(s) still connected.
      GTY776003Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Radio Receiver Assembly)
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      O147-23 (MACC) - Body ground Engine switch on (ACC) 4 to 6 V
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      O147-22 (MIN-) - Body ground Always Below 1 Ω
      O147-24 (SGND) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE RADIO RECEIVER ASSEMBLY. Refer to  REMOVAL [11/2017 - 03/2019]  , or refer to  REMOVAL [03/2019 - ] 

    Result: 

    OK 

    See step  14

  14. CHECK TELEPHONE MICROPHONE ASSEMBLY (OUTPUT TO RADIO RECEIVER ASSEMBLY) 
    GTY825865Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Component with harness connected
    (Telephone Microphone Assembly)
    1. Check the output waveform.
      1. Remove the telephone microphone assembly with the connector(s) still connected.

        Refer to REMOVAL [11/2017 - ]

      2. Connect an oscilloscope to terminal W14-2 (MCO+) and W14-4 (MCO-).
      3. Turn the engine switch on (ACC).
      4. Sound is input to the telephone microphone assembly when the user is closer than 125 mm from the telephone microphone assembly sound holes in the roof headlining holder cover.
      5. Check the signal waveform according to the condition(s) in the table below.
        Item Condition
        Measurement terminal W14-2 (MCO+) - W14-4 (MCO-)
        Tool setting 50 mV/DIV., 500 ms/DIV.
        Vehicle condition
        1. Engine switch on (ACC)
        2. Sound is input to the telephone microphone assembly when the user is closer than 125 mm from the telephone microphone assembly sound holes in the roof headlining holder cover.

        OK

        The waveform is similar to that shown in the illustration.

        HINT: 

        The oscilloscope waveform shown in the illustration is an example for reference only.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE RADIO RECEIVER ASSEMBLY. Refer to  REMOVAL [11/2017 - 03/2019]  , or refer to  REMOVAL [03/2019 - ] 

    Result: 

    NG 

    REPLACE TELEPHONE MICROPHONE ASSEMBLY. Refer to  REMOVAL [11/2017 - ] 

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