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DTC B27A1: Open in Driver Side Electrical Antenna Circuit [09/2015 - ]: Procedure

  1. CHECK CONNECTOR CONNECTION 
    1. Check that the connectors are properly connected to the certification ECU (smart key ECU assembly) and front door outside handle assembly (for driver door).

      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) - FRONT DOOR OUTSIDE HANDLE ASSEMBLY (FOR DRIVER DOOR)) 
    1. Disconnect the R1 and J41 certification ECU (smart key ECU assembly) connectors.
    2. Disconnect the N11 front door outside handle assembly (for driver door) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      R1-17 (CLG1) - N11-4 (ANT1) Always Below 1 Ω
      R1-16 (CG1B) - N11-5 (ANT2) Always Below 1 Ω
      J41-18 (E) - Body ground Always Below 1 Ω
      R1-17 (CLG1) or N11-4 (ANT1) - Body ground Always 10 kΩ or higher
      R1-16 (CG1B) or N11-5 (ANT2) - Body ground Always 10 kΩ or higher
    4. Reconnect the R1 and J41 certification ECU (smart key ECU assembly) connectors.

      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 FRONT DOOR OUTSIDE HANDLE ASSEMBLY (FOR DRIVER DOOR)) 
    GTY617052Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Component with harness connected
    (Certification ECU (Smart Key ECU Assembly))
    *b Waveform 1
    *c Waveform 2 *d Waveform 3
    *e Waveform 4 - -
    1. Using an oscilloscope, check the waveform.

      OK

      Tester Connection Condition Tool Setting Specified Condition
      R1-17 (CLG1) - J41-18 (E) Procedure:
      1. Engine switch off
      2. All doors closed
      3. Electrical key transmitter sub-assembly not inside vehicle
      4. All doors locked through wireless operation

        (electrical key transmitter sub-assembly brought inside detection area*)

      5 V/DIV., 500 ms/DIV. Pulse generation
      (See waveform 1)
      Procedure:
      1. Engine switch off
      2. All doors closed
      3. Electrical key transmitter sub-assembly not inside vehicle
      4. All doors locked through wireless operation

        (electrical key transmitter sub-assembly brought outside detection area*)

      5 V/DIV., 100 ms/DIV. Pulse generation
      (See waveform 2)
      R1-16 (CG1B) - J41-18 (E) Procedure:
      1. Engine switch off
      2. All doors closed
      3. Electrical key transmitter sub-assembly not inside vehicle
      4. All doors locked through wireless operation

        (electrical key transmitter sub-assembly brought inside detection area*)

      5 V/DIV., 500 ms/DIV. Pulse generation
      (See waveform 3)
      Procedure:
      1. Engine switch off
      2. All doors closed
      3. Electrical key transmitter sub-assembly not inside vehicle
      4. All doors locked through wireless operation

        (electrical key transmitter sub-assembly brought outside detection area*)

      5 V/DIV., 100 ms/DIV. Pulse generation
      (See waveform 4)
      1. *: For details about the entry function detection area, refer to Operation Check.

        Refer to OPERATION CHECK [09/2015 - 08/2019] , or refer to OPERATION CHECK [08/2019 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [09/2015 - 08/2016]  , or refer to  REMOVAL [08/2016 - 08/2019]  , or refer to  REMOVAL [08/2019 - ] 

    Result: 

    OK 

    See step  4

  4. REPLACE FRONT DOOR OUTSIDE HANDLE ASSEMBLY (FOR DRIVER DOOR) 
    1. Replace the front door outside handle assembly (for driver door) with a new one or the front door outside handle assembly (for front passenger door) if it is functioning properly.

      Refer to DISASSEMBLY [09/2015 - 08/2016] , or refer to DISASSEMBLY [08/2016 - 12/2017] , or refer to DISASSEMBLY [12/2017 - 08/2019] , or refer to DISASSEMBLY [08/2019 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  5

  5. CLEAR DTC 
    1. Clear the DTCs.

      Body Electrical > Smart Access > Clear DTCs 

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  6

  6. CHECK FOR DTC 
    1. Check for DTCs.

      Body Electrical > Smart Access > Trouble Codes 

      OK

      DTC B27A1 is not output.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END (FRONT DOOR OUTSIDE HANDLE ASSEMBLY (FOR DRIVER DOOR) WAS DEFECTIVE) 

    Result: 

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [09/2015 - 08/2016]  , or refer to  REMOVAL [08/2016 - 08/2019]  , or refer to  REMOVAL [08/2019 - ]