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DTC B27A4-13: Rear Door Electrical Antenna, Front Passenger's Side Circuit Open [11/2021 - ]: Procedure

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

      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) - REAR DOOR OUTSIDE HANDLE ASSEMBLY (FOR FRONT PASSENGER SIDE)) 
    1. Disconnect the G12 certification ECU (smart key ECU assembly) connector.
    2. Disconnect the F8 rear door outside handle assembly (for front passenger side) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      G12-14 (CLG4) - F8-5 (ANT1) Always Below 1 Ω
      G12-13 (CG4B) - F8-2 (ANT2) Always Below 1 Ω
    4. Reconnect the G12 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 REAR DOOR OUTSIDE HANDLE ASSEMBLY (FOR FRONT PASSENGER SIDE)) 
    GTY1082476Courtesy 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
      G12-14 (CLG4) - D58-29 (E) Procedure:
      1. Ignition 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. Ignition 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., 500 ms./DIV. Pulse generation
      (See waveform 2)
      G12-13 (CG4B) - D58-29 (E) Procedure:
      1. Ignition 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. Ignition 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., 500 ms./DIV. Pulse generation
      (See waveform 4)
      1. *: For details about the entry function detection area, refer to Operation Check.

        Refer to OPERATION CHECK [11/2021 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE REAR DOOR OUTSIDE HANDLE ASSEMBLY (FOR FRONT PASSENGER SIDE). Refer to  DISASSEMBLY [11/2021 - ] 

    Result: 

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [11/2021 - ]