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DTC B27A7: Open in Inside Luggage Compartment Electrical Key Oscillator Circuit [12/2017 - ]: Procedure

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

      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. 3 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (INSIDE LUGGAGE COMPARTMENT)) 
    1. Disconnect the R1 and J41 certification ECU (smart key ECU assembly) connectors.
    2. Disconnect the R20*1, T9*2 No. 3 indoor electrical key antenna assembly (inside luggage compartment) connector.
      1. *1: w/o Rear No. 2 Seat
      2. *2: w/ Rear No. 2 Seat
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      W/O REAR NO. 2 SEAT:

      Tester Connection Condition Specified Condition
      R1-11 (CLG7) - R20-1 (ANTE7) Always Below 1 Ω
      R1-10 (CG7B) - R20-3 (CLGB) Always Below 1 Ω
      J41-18 (E) - Body ground Always Below 1 Ω
      R1-11 (CLG7) or R20-1 (ANTE7) - Body ground Always 10 kΩ or higher
      R1-10 (CG7B) or R20-3 (CLGB) - Body ground Always 10 kΩ or higher
      W/ REAR NO. 2 SEAT:

      Tester Connection Condition Specified Condition
      R1-11 (CLG7) - T9-1 (ANTE7) Always Below 1 Ω
      R1-10 (CG7B) - T9-3 (CLGB) Always Below 1 Ω
      J41-18 (E) - Body ground Always Below 1 Ω
      R1-11 (CLG7) or T9-1 (ANTE7) - Body ground Always 10 kΩ or higher
      R1-10 (CG7B) or T9-3 (CLGB) - 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 NO. 3 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (INSIDE LUGGAGE COMPARTMENT)) 
    GTY678333Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    *a Component with harness connected
    (Certification ECU (Smart Key ECU Assembly))
    *b Waveform 1
    *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
      R1-11 (CLG7) - J41-18 (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 1)
      R1-10 (CG7B) - J41-18 (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 1)

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

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

    Result: 

    OK 

    See step  4

  4. REPLACE NO. 3 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (INSIDE LUGGAGE COMPARTMENT) 
    1. Temporarily replace the No. 3 indoor electrical key antenna assembly (inside luggage compartment) with a new or known good one.

      w/o Rear No. 2 Seat: Refer to REMOVAL [09/2015 - ]

      w/ Rear No. 2 Seat: Refer to REMOVAL [12/2017 - ]

      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 B27A7 is not output.

      Result

      Proceed to
      OK
      NG

    Result: 

    OK 

    END (NO. 3 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (INSIDE LUGGAGE COMPARTMENT) WAS DEFECTIVE) 

    Result: 

    NG 

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