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DTC B1579: Voice Recognition Microphone Disconnected [10/2014 - 09/2017]: Procedure

  1. CONFIRM MODEL 
    1. Choose the model to be inspected.

      Result

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

    Result: 

    B 

    See step  7

    Result: 

    A 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (RADIO RECEIVER ASSEMBLY - MAP LIGHT ASSEMBLY) 
    1. Disconnect the I38 radio receiver assembly connector.
    2. Disconnect the T7 map light assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      I38-49 (SNS2) - T7-1 (SNS2) Always Below 1 Ω
      I38-29 (MACC) - T7-4 (MACC) Always Below 1 Ω
      I38-27 (MIN+) - T7-3 (MCO+) Always Below 1 Ω
      I38-48 (MIN-) - T7-2 (MCO-) Always Below 1 Ω
      I38-28 (SGND) - Body ground Always 10 kΩ or higher
      I38-49 (SNS2) or T7-1 (SNS2) - Body ground Always 10 kΩ or higher
      I38-29 (MACC) or T7-4 (MACC) - Body ground Always 10 kΩ or higher
      I38-27 (MIN+) or T7-3 (MCO+) - Body ground Always 10 kΩ or higher
      I38-48 (MIN-) or T7-2 (MCO-) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  3

  3. CHECK RADIO RECEIVER ASSEMBLY 
    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      I38-28 (SGND) - Body ground Always Below 1 Ω
      I38-48 (MIN-) - Body ground Always Below 1 Ω
      GTY506461Courtesy 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 Switch Condition Specified Condition
      I38-29 (MACC) - Body ground Engine switch on (ACC) 4 to 6 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE RADIO RECEIVER ASSEMBLY. Refer to  REMOVAL [10/2014 - 09/2017] 

    Result: 

    OK 

    See step  4

  4. INSPECT MAP LIGHT ASSEMBLY (TELEPHONE MICROPHONE ASSEMBLY) 
    1. Remove the map light assembly (telephone microphone assembly).

      Refer to REMOVAL [10/2014 - ]

      GTY516096Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      1 (SNS2) - 2 (MCO-) Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    See step  6

    Result: 

    OK 

    See step  5

  5. CHECK MAP LIGHT ASSEMBLY 
    1. Reconnect the radio receiver assembly connector.
      GTY500772Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Map Light Assembly)
    2. Reconnect the map light assembly connector.
    3. Turn the engine switch on (ACC).
    4. Connect an oscilloscope to terminals T7-3 (MCO+) and T7-2 (MCO-) of the map light assembly connector.
    5. Check the waveform of the telephone microphone assembly using the oscilloscope.

      Result

      Result Proceed to
      A waveform synchronized with the voice input to the map light assembly is not output. A
      A waveform synchronized with the voice input to the map light assembly is output. B

    Result: 

    B 

    REPLACE RADIO RECEIVER ASSEMBLY. Refer to  REMOVAL [10/2014 - 09/2017] 

    Result: 

    A 

    See step  6

  6. CHECK TELEPHONE MICROPHONE ASSEMBLY 
    1. Replace the telephone microphone assembly.

      Refer to REMOVAL [10/2014 - 09/2017]

    2. Clear the DTCs.

      Refer to DTC CHECK / CLEAR [10/2014 - 09/2017]

      Body Electrical > Navigation System > Clear DTCs 

    3. Recheck for DTCs and check that no DTCs are output.

      Refer to DTC CHECK / CLEAR [10/2014 - 09/2017]

      Body Electrical > Navigation System > Trouble Codes 

      OK

      No DTCs are output.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END (TELEPHONE MICROPHONE ASSEMBLY IS DEFECTIVE) 

    Result: 

    NG 

    REPLACE MAP LIGHT ASSEMBLY. Refer to  REMOVAL [10/2014 - ] 

  7. CHECK HARNESS AND CONNECTOR (RADIO RECEIVER ASSEMBLY - MAP LIGHT ASSEMBLY) 
    1. Disconnect the I38 radio receiver assembly connector.
    2. Disconnect the T7 map light assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      I38-49 (SNS2) - T7-1 (SNS2) Always Below 1 Ω
      I38-49 (SNS2) or T7-1 (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  8

  8. CHECK HARNESS AND CONNECTOR (RADIO RECEIVER ASSEMBLY - DCM [TELEMATICS TRANSCEIVER]) 
    1. Disconnect the I38 radio receiver assembly connector.
    2. Disconnect the I40 DCM (telematics transceiver) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      I38-27 (MIN+) - I40-18 (MCO+) Always Below 1 Ω
      I38-48 (MIN-) - I40-19 (MCO-) Always Below 1 Ω
      I38-28 (SGND) - Body ground Always 10 kΩ or higher
      I38-27 (MIN+) or I40-18 (MCO+) - Body ground Always 10 kΩ or higher
      I38-48 (MIN-) or I40-19 (MCO-) - 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 HARNESS AND CONNECTOR (DCM [TELEMATICS TRANSCEIVER] - MAP LIGHT ASSEMBLY) 
    1. Disconnect the I40 DCM (telematics transceiver) connector.
    2. Disconnect the T7 map light assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      I40-33 (MCVD) - T7-4 (MACC) Always Below 1 Ω
      I40-34 (MCI+) - T7-3 (MCO+) Always Below 1 Ω
      I40-35 (MCI-) - T7-2 (MCO-) Always Below 1 Ω
      I40-32 (SGND) - Body ground Always 10 kΩ or higher
      I40-33 (MCVD) or T7-4 (MACC) - Body ground Always 10 kΩ or higher
      I40-34 (MCI+) or T7-3 (MCO+) - Body ground Always 10 kΩ or higher
      I40-35 (MCI-) or T7-2 (MCO-) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  10

  10. CHECK RADIO RECEIVER ASSEMBLY 
    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      I38-28 (SGND) - Body ground Always Below 1 Ω
      I38-48 (MIN-) - Body ground Always Below 1 Ω
      GTY519465Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (Radio Receiver Assembly)

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE RADIO RECEIVER ASSEMBLY. Refer to  REMOVAL [10/2014 - 09/2017] 

    Result: 

    OK 

    See step  11

  11. CHECK DCM (TELEMATICS TRANSCEIVER) 
    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      I40-32 (SGND) - Body ground Always Below 1 Ω
      I40-35 (MCI-) - Body ground Always Below 1 Ω
      GTY511281Courtesy 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 Switch Condition Specified Condition
      I40-33 (MCVD) - Body ground Engine switch on (ACC) 4 to 6 V

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    See step  4

    Result: 

    NG 

    REPLACE DCM (TELEMATICS TRANSCEIVER). Refer to  REMOVAL [10/2014 - 09/2017] 

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