B27A1

DTC Code	DTC Name
B27A1	Open in Driver Side Electrical Antenna Circuit

DESCRIPTION

The certification ECU (smart key ECU assembly) generates a request signal and transmits the signal to the door outside handle sub-assembly (for driver door) (electrical key antenna) at intervals of 0.25 seconds. For the door outside handle sub-assembly (for driver door) (electrical key antenna) to detect when the electrical key transmitter sub-assembly is brought close to the vehicle, a signal requesting a response from the electrical key transmitter sub-assembly is transmitted within approximately 1 m (3.28 ft.) of the driver door at intervals of 0.25 seconds. DTC B27A1 is stored by the certification ECU (smart key ECU assembly) when an open is detected between the certification ECU (smart key ECU assembly) and door outside handle sub-assembly (for driver door) (electrical key antenna) (between terminals CLG1 and ANT1, or terminals CG1B and ANT2).

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	Note
B27A1	Open in Driver Side Electrical Antenna Circuit	An open is detected in the circuit between the certification ECU (smart key ECU assembly) and door outside handle sub-assembly (for driver door) (CLG1 - ANT1, CG1B - ANT2) (This is detected by the malfunction detection circuit in the certification ECU (smart key ECU assembly)) (1 trip detection logic*).	Certification ECU (smart key ECU assembly) Door outside handle sub-assembly (for driver door) Harness or connector	DTC Output Confirmation Operation: Any time

*: Only output while a malfunction is present.

Vehicle Condition and Fail-safe Operation when Malfunction Detected
Vehicle Condition when Malfunction Detected	Fail-safe Operation when Malfunction Detected
Entry lock/unlock operation cannot be performed for driver door	-

Related Data List and Active Test
DTC No.	Data List and Active Test
B27A1	Key diagnostic mode can be used to perform troubleshooting

WIRING DIAGRAM

CAUTION / NOTICE / HINT

Note

When using the GTS with the engine switch off, connect the GTS to the DLC3 and turn a courtesy light switch on and off at intervals of 1.5 seconds or less until communication between the GTS and the vehicle begins. Then select Model Code "KEY REGIST" under manual mode and enter the following menus: Body Electrical /Entry&Start. While using the GTS, periodically turn a courtesy light switch on and off at intervals of 1.5 seconds or less to maintain communication between the GTS and the vehicle.
The entry and start system (for Entry Function) uses the LIN communication system and CAN communication system. Inspect the communication function by following How to Proceed with Troubleshooting. Troubleshoot the entry and start system (for Entry Function) after confirming that the communication systems are functioning properly.

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Before replacing the certification ECU (smart key ECU assembly), refer to the Service Bulletin.
After repair, confirm that no DTCs are output.

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PROCEDURE

CHECK CONNECTOR CONNECTION

Check that the connectors are properly connected to the certification ECU (smart key ECU assembly) and door outside handle sub-assembly (for driver door).

OK
Connectors are properly connected.

Result

Proceed to
OK
NG

NG

CONNECT CONNECTORS PROPERLY

OK

CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - DOOR OUTSIDE HANDLE SUB-ASSEMBLY (FOR DRIVER DOOR))

Disconnect the X23 certification ECU (smart key ECU assembly) connector.
Disconnect the W1*1 or V1*2 door outside handle sub-assembly (for driver door) connector.
- *1: for LHD
- *2: for RHD

Measure the resistance according to the value(s) in the table below.

Standard Resistance

for LHD:
Tester Connection	Condition	Specified Condition
X23-17 (CLG1) - W1-2 (ANT1)	Always	Below 1 Ω
X23-16 (CG1B) - W1-1 (ANT2)	Always	Below 1 Ω

for RHD:
Tester Connection	Condition	Specified Condition
X23-17 (CLG1) - V1-2 (ANT1)	Always	Below 1 Ω
X23-16 (CG1B) - V1-1 (ANT2)	Always	Below 1 Ω

Reconnect the X23 certification ECU (smart key ECU assembly) connector.

Result

Proceed to
OK
NG

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) (OUTPUT TO DOOR OUTSIDE HANDLE SUB-ASSEMBLY (FOR DRIVER DOOR))

*a

Component with harness connected

(Certification ECU (Smart Key ECU Assembly))

*b

Waveform 1

*c

Waveform 2

*d

Waveform 3

*e

Waveform 4

-

Using an oscilloscope, check the waveform.

OK

Tester Connection	Condition	Tool Setting	Specified Condition
X23-17 (CLG1) - P66-18 (E)	Procedure: Engine switch off All doors closed Electrical key transmitter sub-assembly not inside vehicle All doors locked through wireless operation (electrical key transmitter sub-assembly brought inside detection area*)	5 V/DIV., 500 ms./DIV.	Pulse generation (See waveform 1)
X23-17 (CLG1) - P66-18 (E)	Procedure: Engine switch off All doors closed Electrical key transmitter sub-assembly not inside vehicle All doors locked through wireless operation (electrical key transmitter sub-assembly brought outside detection area*)	5 V/DIV., 100 ms./DIV.	Pulse generation (See waveform 2)
X23-16 (CG1B) - P66-18 (E)	Procedure: Engine switch off All doors closed Electrical key transmitter sub-assembly not inside vehicle All doors locked through wireless operation (electrical key transmitter sub-assembly brought inside detection area*)	5 V/DIV., 500 ms./DIV.	Pulse generation (See waveform 3)
X23-16 (CG1B) - P66-18 (E)	Procedure: Engine switch off All doors closed Electrical key transmitter sub-assembly not inside vehicle All doors locked through wireless operation (electrical key transmitter sub-assembly brought outside detection area*)	5 V/DIV., 100 ms./DIV.	Pulse generation (See waveform 4)

*: For details about the entry function detection area, refer to Operation Check.

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Result

Proceed to
OK
NG

OK

REPLACE DOOR OUTSIDE HANDLE SUB-ASSEMBLY (FOR DRIVER DOOR) Click here

NG

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

ENTRY AND START SYSTEM(for Entry Function), Diagnostic DTC:B27A1