DTC B1579: Voice Recognition Microphone Disconnected [11/2018 - 10/2019]: Procedure

2020 Toyota RAV4 XLE, AWDSECTION Procedure
  1. CHECK VEHICLE TYPE 
    1. Check the vehicle type.

      Result

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

    Result: 

    See step  5

    Result: 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - MAP LIGHT ASSEMBLY) 
    1. Disconnect the G2 radio and display receiver assembly connector.
    2. Disconnect the P14 map light assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      FOR TMC MADE:

      Tester Connection Condition Specified Condition
      G2-25 (SNS2) - P14-5 (SNS2) Always Below 1 Ω
      G2-25 (SNS2) - Body ground Always 10 kΩ or higher
      FOR TMMC MADE:

      Tester Connection Condition Specified Condition
      G2-25 (SNS2) - P14-6 (SNS2) Always Below 1 Ω
      G2-25 (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  3

  3. CHECK HARNESS AND CONNECTOR (DCM [TELEMATICS TRANSCEIVER] - TELEPHONE MICROPHONE ASSEMBLY) 
    1. Disconnect the G9 DCM (telematics transceiver) connector.
    2. Disconnect the P14 telephone microphone assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      FOR TMC MADE:

      Tester Connection Condition Specified Condition
      G9-35 (MCI-) - P14-5 (MCO-) Always Below 1 Ω
      G9-35 (MCI-) - Body ground Always 10 kΩ or higher
      FOR TMMC MADE:

      Tester Connection Condition Specified Condition
      G9-35 (MCI-) - P14-6 (MCO-) Always Below 1 Ω
      G9-35 (MCI-) - 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. CHECK DCM (TELEMATICS TRANSCEIVER) (MCI-) 
    1. Remove the DCM (telematics transceiver) with the connector(s) still connected.
      GTY903648Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (DCM [Telematics Transceiver])

      Refer to REMOVAL [11/2018 - 10/2019]

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      G9-35 (MCI-) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    See step  6

    Result: 

    NG 

    REPLACE DCM (TELEMATICS TRANSCEIVER) 

    Refer to REMOVAL [11/2018 - 10/2019]

  5. CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - TELEPHONE MICROPHONE ASSEMBLY) 
    1. Disconnect the G2 radio and display receiver assembly connector.
    2. Disconnect the P14 map light assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      FOR TMC MADE:

      Tester Connection Condition Specified Condition
      G2-25 (SNS2) - P14-4 (SNS2) Always Below 1 Ω
      G2-22 (MIN-) - P14-5 (MCO-) Always Below 1 Ω
      G2-25 (SNS2) - Body ground Always 10 kΩ or higher
      G2-22 (MIN-) - Body ground Always 10 kΩ or higher
      FOR TMMC MADE:

      Tester Connection Condition Specified Condition
      G2-25 (SNS2) - P14-5 (SNS2) Always Below 1 Ω
      G2-22 (MIN-) - P14-6 (MCO-) Always Below 1 Ω
      G2-25 (SNS2) - Body ground Always 10 kΩ or higher
      G2-22 (MIN-) - Body ground Always 10 kΩ or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  6

  6. INSPECT MAP LIGHT ASSEMBLY 
    1. Remove the map light assembly.

      Refer to REMOVAL [11/2018 - ]

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      FOR TMC MADE:

      Tester Connection Condition Specified Condition
      4 (SNS2) - 5 (MCO-) Always Below 1 Ω
      FOR TMMC MADE:

      Tester Connection Condition Specified Condition
      5 (SNS2) - 6 (MCO-) Always Below 1 Ω
      GTY1250496Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *A for TMC Made
      *B for TMMC Made
      *a Component without harness connected
      (Map Light Assembly)

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY 

    Refer to REMOVAL [11/2018 - 10/2022]

    Result: 

    NG 

    See step  7

  7. INSPECT MAP LIGHT ASSEMBLY 
    1. Remove the map light assembly.
      GTY1250556Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *A for TMC Made
      *B for TMMC Made
      *a Component without harness connected
      (Map Light Assembly [Wire Harness Side])
      *b Component without harness connected
      (Map Light Assembly [Telephone Microphone Assembly Side])

      Refer to REMOVAL [11/2018 - ]

    2. Disconnect the telephone microphone assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      FOR TMC MADE:

      Tester Connection Condition Specified Condition
      P14-4 (SNS2) - C-1 (SNS2) Always Below 1 Ω
      P14-5 (MCO-) - C-2 (MIC-) Always Below 1 Ω
      FOR TMMC MADE:

      Tester Connection Condition Specified Condition
      P14-5 (SNS2) - C-1 (SNS2) Always Below 1 Ω
      P14-6 (MCO-) - C-2 (MIC-) Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE TELEPHONE MICROPHONE ASSEMBLY 

    Refer to REMOVAL [11/2018 - 12/2021]

    Result: 

    NG 

    REPLACE MAP LIGHT ASSEMBLY 

    Refer to REMOVAL [11/2018 - ]

RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
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