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DTC B27A8: Open in Outside Luggage Compartment Electrical Key Antenna Circuit [10/2018 - ]: Procedure

  1. CHECK CONNECTOR CONNECTION 
    1. Check that the connectors are properly connected to the certification ECU (smart key ECU assembly) and electrical key antenna (outside luggage compartment).

      OK

      Connectors are properly connected.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    CONNECT CONNECTORS PROPERLY 

    Result: 

    OK 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - ELECTRICAL KEY ANTENNA (OUTSIDE LUGGAGE COMPARTMENT)) 
    1. Disconnect the N61 certification ECU (smart key ECU assembly) connector.
    2. Disconnect the Q1 electrical key antenna (outside luggage compartment) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      N61-13 (CLG8) - Q1-2 (ANTE8) Always Below 1 Ω
      N61-12 (CG8B) - Q1-1 (CLGB) Always Below 1 Ω
    4. Reconnect the N61 certification ECU (smart key ECU assembly) connector.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  3

  3. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) (OUTPUT TO ELECTRICAL KEY ANTENNA (OUTSIDE LUGGAGE COMPARTMENT)) 
    GTY788743Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Component with harness connected
    (Certification ECU (Smart Key ECU Assembly))
    *b Waveform 1
    1. Using an oscilloscope, check the waveform.

      OK

      Tester Connection Condition Tool Setting Specified Condition
      N61-13 (CLG8) - F44-18 (E) Procedure:
      1. Power switch off
      2. Electrical key transmitter sub-assembly brought outside vehicle
      3. All doors closed
      4. Back door opener switch off → on
      2 V/DIV., 500 ms./DIV. Pulse generation
      (See waveform 1)
      N61-12 (CG8B) - F44-18 (E) Procedure:
      1. Power switch off
      2. Electrical key transmitter sub-assembly brought outside vehicle
      3. All doors closed
      4. Back door opener switch off → on
      2 V/DIV., 500 ms./DIV. Pulse generation
      (See waveform 1)

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE ELECTRICAL KEY ANTENNA (OUTSIDE LUGGAGE COMPARTMENT). Refer to  REMOVAL [10/2018 - ] 

    Result: 

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [10/2018 - 07/2022]  , or refer to  REMOVAL [07/2022 - ]