Mute Signal Circuit between Radio Receiver and Telematics Transceiver [07/2020 - ]: Procedure

2018 Toyota Prius Two EcoSECTION Procedure
  1. INSPECT DCM (TELEMATICS TRANSCEIVER) 
    1. Measure the voltage according to the value(s) in the table below.
      GTY984160Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Component with harness connected
      (DCM (Telematics Transceiver))

      Standard Voltage

      Tester Connection Condition Specified Condition
      F128-14 (MUTE) - Body ground Power switch on (ACC)
      Audio system playing
      → Emergency call mode
      2.0 V or higher
      → Below 1 V

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE [07/2020 - ] 

    Result: 

    NG 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - DCM (TELEMATICS TRANSCEIVER)) 
    1. Disconnect the F119 radio and display receiver assembly connector.
    2. Disconnect the F128 DCM (telematics transceiver) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F119-3 (TMUT) - F128-14 (MUTE) Always Below 1 Ω
      F119-3 (TMUT) or F128-14 (MUTE) - 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. INSPECT RADIO AND DISPLAY RECEIVER ASSEMBLY 
    1. Disconnect the F128 DCM (telematics transceiver) connector.
    2. Measure the voltage according to the value(s) in the table below.
      GTY983428Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to DCM (Telematics Transceiver))

      Standard Voltage

      Tester Connection Condition Specified Condition
      F128-14 (MUTE) - Body ground Power switch on (ACC) 2.0 V or higher

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE DCM (TELEMATICS TRANSCEIVER). Refer to  REMOVAL [07/2020 - ] 

    Result: 

    NG 

    REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY. Refer to  REMOVAL [08/2019 - ] 

RENDER: 1.0x

NO RELATED

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

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