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DTC B27A7: Open in Inside Luggage Compartment Electrical Key Oscillator Circuit [06/2018 - ]: Procedure

  1. CHECK CONNECTOR CONNECTION 
    1. Check that the connectors are properly connected to the certification ECU (smart key ECU assembly) and No. 2 indoor electrical key antenna assembly (inside 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) - NO. 2 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (INSIDE LUGGAGE COMPARTMENT)) 
    1. Disconnect the N9 certification ECU (smart key ECU assembly) connector.
    2. Disconnect the N12 No. 2 indoor electrical key antenna assembly (inside luggage compartment) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      N9-11 (CLG7) - N12-1 (ANTE7) Always Below 1 Ω
      N9-10 (CG7B) - N12-3 (CLGB) Always Below 1 Ω
    4. Reconnect the N9 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 (OUTPUT TO NO. 2 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (INSIDE LUGGAGE COMPARTMENT)) 
    GTY789688Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Component with harness connected
    (Certification ECU (Smart Key ECU Assembly))
    *b Waveform 1
    *c Driver door lock sensor not touched *d Driver door lock sensor touched
    1. Using an oscilloscope, check the waveform.

      OK

      Tester Connection Condition Tool Setting Specified Condition
      N9-11 (CLG7) - G47-18 (E) Procedure:
      1. Door is closed
      2. Engine switch off
      3. Electrical key transmitter sub-assembly not inside vehicle
      4. Driver door lock sensor touched
      2 V/DIV., 500 ms/DIV. Pulse generation
      (See waveform 1)
      N9-10 (CG7B) - G47-18 (E) Procedure:
      1. Door is closed
      2. Engine switch off
      3. Electrical key transmitter sub-assembly not inside vehicle
      4. Driver door lock sensor touched
      2 V/DIV., 500 ms/DIV. Pulse generation
      (See waveform 1)

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE NO. 2 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (INSIDE LUGGAGE COMPARTMENT). Refer to  REMOVAL [06/2018 - 08/2021]  , or refer to  REMOVAL [08/2021 - 09/2022]  , or refer to  REMOVAL [09/2022 - ] 

    Result: 

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [06/2018 - 08/2021]  , or refer to  REMOVAL [08/2021 - 09/2022]  , or refer to  REMOVAL [09/2022 - ]