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DTC B27A5: Open in Front Floor Electrical Key Oscillator Circuit [12/2013 - ]: Procedure

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

      OK

      Connectors are properly connected.

      Result

      Proceed to
      OK
      NG

    Result:  2

    NG 

    CONNECT CONNECTORS PROPERLY 

    Result:  1

    OK 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - NO. 1 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (FRONT FLOOR)) 
    1. Disconnect the F13 certification ECU (smart key ECU assembly) connector.
    2. Disconnect the F39 No. 1 indoor electrical key antenna assembly (front floor) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      F13-21 (CLG5) - F39-1 (ANTE5) Always Below 1 Ω
      F13-20 (CG5B) - F39-3 (CLGB) Always Below 1 Ω
      F13-11 (E) - Body ground Always Below 1 Ω
      F13-21 (CLG5) or F39-1 (ANTE5) - Body ground Always 10 kΩ or higher
      F13-20 (CG5B) or F39-3 (CLGB) - Body ground Always 10 kΩ or higher
    4. Reconnect the F13 certification ECU (smart key ECU assembly) connector.

      Result

      Proceed to
      OK
      NG

    Result:  2

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result:  1

    OK 

    See step  3

  3. INSPECT CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) (OUTPUT TO NO. 1 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (FRONT FLOOR)) 
    GTY428804Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Component with harness connected
    (Certification ECU (Smart Key ECU Assembly))
    *b Waveform 1
    *c For 30 seconds after closing any door using the door outside handle *d 30 seconds or more have elapsed after closing any door using the door outside handle
    1. Using an oscilloscope, check the waveform.

      OK

      Tester Connection Condition Tool Setting Specified Condition
      F13-21 (CLG5) - F13-11 (E) Procedure:
      1. Engine switch off
      2. Electrical key transmitter sub-assembly not inside vehicle
      3. Within 30 seconds of closing any door using the door outside handle
      2 V/DIV., 500 ms/DIV. Pulse generation
      (See waveform 1)
      F13-20 (CG5B) - F13-11 (E) Procedure:
      1. Engine switch off
      2. Electrical key transmitter sub-assembly not inside vehicle
      3. Within 30 seconds of closing any door using the door outside handle
      2 V/DIV., 500 ms/DIV. Pulse generation
      (See waveform 1)

      Result

      Proceed to
      OK
      NG

    Result:  2

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [12/2013 - ] 

    Result:  1

    OK 

    See step  4

  4. REPLACE NO. 1 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (FRONT FLOOR) 
    1. Temporarily replace the No. 1 indoor electrical key antenna assembly (front floor) with a new one.

      Refer to REMOVAL [12/2013 - ]

    NEXT 

  5. CLEAR DTC 
    1. Clear the DTCs.

      Body Electrical > Smart Key > Clear DTCs 

    NEXT 

  6. CHECK FOR DTC 
    1. Check for DTCs.

      Body Electrical > Smart Key > Trouble Codes 

      OK

      DTC B27A5 is not output.

      Result

      Proceed to
      OK
      NG

    Result:  1

    OK 

    END (NO. 1 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (FRONT FLOOR) WAS DEFECTIVE) 

    Result:  2

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [12/2013 - ]