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DTC B27A9: Open in Floor/Extra Electrical Key Oscillator Circuit [09/2016 - 05/2019]: Procedure

  1. CHECK CONNECTOR CONNECTION 
    1. Check that the connectors are properly connected to the certification ECU (smart key ECU assembly) and No. 2 electrical key antenna (extra antenna).

      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 ELECTRICAL KEY ANTENNA (EXTRA ANTENNA)) 
    1. Disconnect the N54 and I1 certification ECU (smart key ECU assembly) connectors.
    2. Disconnect the N81 No 2 electrical key antenna (extra antenna) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      N54-4 (CLGP) - N81-2 (ANTEP) Always Below 1 Ω
      N54-3 (CGPB) - N81-1 (CLGB) Always Below 1 Ω
      I1-18 (E) - Body ground Always Below 1 Ω
      N54-4 (CLGP) or N81-2 (ANTEP) - Body ground Always 10 kΩ or higher
      N54-3 (CGPB) or N81-1 (CLGB) - Body ground Always 10 kΩ or higher
    4. Reconnect the N54 and I1 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)) 
    GTY692402Courtesy 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
      N54-4 (CLGP) - I1-18 (E) Procedure:
      1. Power 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. Power 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)
      N54-3 (CGPB) - I1-18 (E) Procedure:
      1. Power 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. Power 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 [09/2016 - ]

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [09/2016 - 07/2020] 

    Result: 

    OK 

    See step  4

  4. REPLACE NO. 2 ELECTRICAL KEY ANTENNA (EXTRA ANTENNA) 
    1. Temporarily replace the No. 2 electrical key antenna (extra antenna) with a new or known good one.

      Refer to REMOVAL [09/2016 - ]

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  5

  5. CLEAR DTC 
    1. Clear the DTCs.

      Body Electrical > Smart Key > Clear DTCs 

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  6

  6. CHECK FOR DTC 
    1. Check for DTCs.

      Body Electrical > Smart Key > Trouble Codes 

      OK

      DTC B27A9 is not output.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END (NO. 2 ELECTRICAL KEY ANTENNA (EXTRA ANTENNA) WAS DEFECTIVE) 

    Result: 

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [09/2016 - 07/2020] 

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