DTC B27A7: Open in Inside Luggage Compartment Electrical Key Oscillator Circuit [09/2015 - 12/2017]: Procedure

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

1. Disconnect the R1 and J41 certification ECU (smart key ECU assembly) connectors.
2. Disconnect the R20 No. 3 indoor electrical key antenna assembly (inside luggage compartment) connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   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

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

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

1. Using an oscilloscope, check the waveform.

   OK

   Tester Connection	Condition	Tool Setting	Specified Condition
   R1-11 (CLG7) - J41-18 (E)	Procedure: Engine switch off Electrical key transmitter sub-assembly not inside vehicle 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: Engine switch off Electrical key transmitter sub-assembly not inside vehicle 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 [09/2015 - 08/2016]  , or refer to  REMOVAL [08/2016 - 08/2019] 

Result: 

OK 

See step  4

1. Temporarily replace the No. 3 indoor electrical key antenna assembly (inside luggage compartment) with a new or known good one.

   Refer to REMOVAL [09/2015 - ]

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  5

1. Clear the DTCs.

   Body Electrical > Smart Access > Clear DTCs 

   Result

   Proceed to
   NEXT

Result: 

NEXT 

See step  6

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 [09/2015 - 08/2016]  , or refer to  REMOVAL [08/2016 - 08/2019]