Toyota Venza: Open in Driver Side Electrical Antenna Circuit (B27A1)

Toyota Venza Service Manual / Theft Deterrent / Keyless Entry / Smart Key System(for Entry Function) / Open in Driver Side Electrical Antenna Circuit (B27A1)

DESCRIPTION

The certification ECU (smart key ECU assembly) generates a request signal and sends it to the electrical key oscillator built into the front door outside handle assembly (for driver side) at 0.25-second intervals. To detect a key near the driver door, the front door outside handle assembly (for driver side) creates a detection area with a radius of approximately 1.0 m (3.28 ft.) from the driver door at 0.25-second intervals.

DTC B27A1 is detected by the certification ECU (smart key ECU assembly) if an open circuit is detected between the certification ECU (smart key ECU assembly) and front door outside handle assembly (for driver side) terminals (between CLG1 and ANT1, or CG1B and ANT2).

DTC No.	DTC Detection Condition	Trouble Area
B27A1	Open circuit detected between the certification ECU (smart key ECU assembly) and front door outside handle assembly (for driver side) terminals (between CLG1 and ANT1, or CG1B and ANT2).	Front door outside handle assembly (for driver side) Certification ECU (smart key ECU assembly) Wire harness or connector

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

The smart key system (for entry function) uses a multiplex communication system (LIN communication system) and CAN communication system. Inspect the communication function by following How to Proceed with Troubleshooting (See page ). Troubleshoot the smart key system (for entry
function) after confirming that the communication system is functioning properly.

PROCEDURE

1.	CHECK CONNECTOR (CONNECTOR CONNECTION CONDITION)

(a) Turn the engine switch off.

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

OK:

Connectors are properly connected.

CONNECT CONNECTORS PROPERLY

2.	CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - FRONT DOOR OUTSIDE HANDLE)

(a) Disconnect the certification ECU (smart key ECU assembly) connector.

(b) Disconnect the front door outside handle assembly (for driver side) connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
D25-3 (CLG1) - z3-6 (ANT1)	Always	Below 1 Ω
D25-4 (CG1B) - z3-3 (ANT2)	Always	Below 1 Ω
D25-3 (CLG1) - Body ground	Always	10 kΩ or higher
D25-4 (CG1B) - Body ground	Always	10 kΩ or higher
z3-6 (ANT1) - Body ground	Always	10 kΩ or higher
z3-3 (ANT2) - Body ground	Always	10 kΩ or higher

Text in Illustration

Front view of wire harness connector

(to Certification ECU (Smart Key ECU Assembly))

Front view of wire harness connector

(to Front Door Outside Handle Assembly (for Driver Side))

REPAIR OR REPLACE HARNESS OR CONNECTOR

3.	CHECK HARNESS AND CONNECTOR (FRONT DOOR OUTSIDE HANDLE - BODY GROUND)

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
z3-2 (GND) - Body ground	Always	Below 1 Ω

Text in Illustration

*1	Front view of wire harness connector (to Front Door Outside Handle Assembly (for Driver Side))

REPAIR OR REPLACE HARNESS OR CONNECTOR

4.	INSPECT CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) (INDOOR ELECTRICAL KEY OSCILLATOR SIGNAL OUTPUT)

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

(b) Measure the resistance and check for pulses according to the value(s) in the table below.

Standard Resistance:

Tester Connection	Condition	Specified Condition
D25-15 (E) - Body ground	Always	Below 1 Ω

Standard:

Tester Connection	Condition	Specified Condition
D25-3 (CLG1) - D25-15 (E)	Engine switch off All door closed Key not in cabin	No pulse generation
D25-3 (CLG1) - D25-15 (E)	Engine switch off All door closed Key not in cabin All doors locked by wireless lock function	Pulse generation
D25-4 (CG1B) - D25-15 (E)	Engine switch off All door closed Key not in cabin	No pulse generation
D25-4 (CG1B) - D25-15 (E)	Engine switch off All door closed Key not in cabin All doors locked by wireless lock function	Pulse generation

Text in Illustration

*1	Component with harness connected (Certification ECU (Smart Key ECU Assembly))

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

5.	REPLACE FRONT DOOR OUTSIDE HANDLE ASSEMBLY (for Driver Side)

(a) Replace the front door outside handle assembly (for driver side) (See page ).

6.	CHECK DTC OUTPUT

(a) Clear the DTCs (See page ).

(b) Recheck for DTCs.

OK:

DTC B27A1 is not output.

END (FRONT DOOR OUTSIDE HANDLE ASSEMBLY WAS DEFECTIVE)

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

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