DTC B27A1: Open in Driver Side Electrical Antenna Circuit: Procedure

1. Turn the engine switch off.
2. Check that the connectors are properly connected to the certification ECU (smart key ECU assembly) and front door outside handle assembly LH.

   OK

   Connectors are properly connected.

NG → CONNECT CONNECTORS PROPERLY 

OK: Go to next step 

1. Disconnect the C35 certification ECU (smart key ECU assembly) connector.
2. Disconnect the G1 front door outside handle assembly LH connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   C35-3 (CLG1) - G1-6 (ANT1)	Always	Below 1 Ω
   C35-4 (CG1B) - G1-3 (ANT2)	Always	Below 1 Ω
   C35-15 (E) - Body ground	Always	Below 1 Ω
   G1-2 (GND) - Body ground	Always	Below 1 Ω
   C35-3 (CLG1) or G1-6 (ANT1) - Body ground	Always	10 kΩ or higher
   C35-4 (CG1B) or G1-3 (ANT2) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Connect the C35 certification ECU (smart key ECU assembly) connector.
   Fig 1: Checking Certification ECU (Output To Driver Side Electrical Key Antenna) With Waveform

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   TEXT IN ILLUSTRATION
   
   

   *1	Waveform 1	*2	Waveform 2
   *a	Component with harness connected (Certification ECU [Smart Key ECU Assembly])	-	-

2. Connect the G1 front door outside handle assembly LH connector.
3. Using an oscilloscope, check the waveform.

   OK

   Tester Connection	Condition	Tool Setting	Specified Condition
   C35-3 (CLG1) - C35-15 (E)	Procedure:  Engine switch off Electrical key transmitter brought outside vehicle All doors closed Electrical key transmitter not inside vehicle Electrical key transmitter brought inside detection area*1 All doors locked through wireless operation	2 V/DIV., 500 ms/DIV.	Pulse generation (See waveform 1 in)
   C35-3 (CLG1) - C35-15 (E)	Procedure:  Engine switch off Electrical key transmitter brought outside vehicle All doors closed Electrical key transmitter not inside vehicle Electrical key transmitter brought outside detection area*2 All doors locked through wireless operation	2 V/DIV., 500 ms/DIV.	Pulse generation (See waveform 2)
   C35-4 (CG1B) - C35-15 (E)	Procedure:  Engine switch off Electrical key transmitter brought outside vehicle All doors closed Electrical key transmitter not inside vehicle All doors locked with electrical key transmitter	2 V/DIV., 500 ms/DIV.	Pulse generation (See waveform 2)

   • *1: For details about the areas that are inside the entry function detection area, refer to Operation Check. Refer to OPERATION CHECK .
   • *2: For details about the areas that are outside the entry function detection area, refer to Operation Check. Refer to OPERATION CHECK .

NG → See step   7 

OK: Go to next step 

1. Temporarily replace the front door outside handle assembly LH with a new or normally functioning one. Refer to DISASSEMBLY .

NEXT: Go to next step 

1. Clear the DTCs. Refer to DTC CHECK / CLEAR .

NEXT: Go to next step 

1. Check for DTCs. Refer to DTC CHECK / CLEAR .

   OK

   DTC B27A1 is not output.

NG → See step   7 

OK → END (FRONT DOOR OUTSIDE HANDLE ASSEMBLY LH IS DEFECTIVE)