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DTC B27A6: Open in Rear Floor Electrical Key Oscillator Circuit [08/2019 - ]: Procedure

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  1. CHECK CONNECTION OF CONNECTOR 
    1. Check that the connectors are properly connected to the certification ECU (smart key ECU assembly) and No. 3 indoor electrical key antenna assembly (rear floor).

      Result

      Result Proceed to
      The connectors are properly connected A
      The connectors are not properly connected B

    Result: 

    CONNECT CONNECTORS PROPERLY 

    Result: 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - NO. 3 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (REAR FLOOR)) 
    1. Disconnect the H198 certification ECU (smart key ECU assembly) connector.
    2. Disconnect the P36 No. 3 indoor electrical key antenna assembly (rear floor) connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      H198-15 (CLG6) - P36-1 (ANTE6) Always Below 1 Ω
      H198-14 (CG6B) - P36-2 (CLGB) Always Below 1 Ω
    4. Reconnect the H198 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 NO. 3 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (REAR FLOOR)) 
    GTY841996Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Component with harness connected
    (Certification ECU (Smart Key ECU Assembly))
    *b Waveform
    *c For 30 seconds after any door closed *d After 30 seconds or more have elapsed since any door closed
    1. Using an oscilloscope, check the waveform.

      OK

      Tester Connection Condition Tool Setting Specified Condition
      H198-15 (CLG6) - H199-11 (E) Procedure:
      1. Engine switch off
      2. Electrical key transmitter sub-assembly not inside vehicle
      3. Within 30 seconds of closing any door
      2 V/DIV., 500 ms./DIV. Pulse generation
      (See waveform)
      H198-14 (CG6B) - H199-11 (E) Procedure:
      1. Engine switch off
      2. Electrical key transmitter sub-assembly not inside vehicle
      3. Within 30 seconds of closing any door
      2 V/DIV., 500 ms./DIV. Pulse generation
      (See waveform)

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    REPLACE NO. 3 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (REAR FLOOR). Refer to  REMOVAL [08/2019 - ] 

    Result: 

    NG 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [08/2019 - ]