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DTC    B27A1    Open in Driver Side Electrical Antenna Circuit

for Preparation Click here


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).
  1. Front door outside handle assembly (for driver side)
  2. Certification ECU (smart key ECU assembly)
  3. Wire harness or connector

WIRING DIAGRAM


B203527E09


INSPECTION PROCEDURE

NOTICE:
The entry and start system (for entry function) uses a LIN communication system and CAN communication system. Inspect the communication function by following How to Proceed with Troubleshooting (Click here). Troubleshoot the entry and start system (for entry function) after confirming that the communication system is functioning properly.

1.CHECK CONNECTOR (CONNECTOR CONNECTION CONDITION)

  1. Turn the power switch off.

  1. 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.



NG
CONNECT CONNECTORS PROPERLY
OK


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

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



    B203512E33

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

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

    Standard Resistance:
    for LHD 
    Tester Connection
    		Condition
    		Specified Condition
    L62-3 (CLG1) - z3-6 (ANT1)
    		Always
    		Below 1 Ω
    L62-4 (CG1B) - z3-3 (ANT2)
    		Always
    		Below 1 Ω
    L62-3 (CLG1) - Body ground
    		Always
    		10 kΩ or higher
    L62-4 (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
    for RHD 
    Tester Connection
    		Condition
    		Specified Condition
    L62-3 (CLG1) - z4-6 (ANT1)
    		Always
    		Below 1 Ω
    L62-4 (CG1B) - z4-3 (ANT2)
    		Always
    		Below 1 Ω
    L62-3 (CLG1) - Body ground
    		Always
    		10 kΩ or higher
    L62-4 (CG1B) - Body ground
    		Always
    		10 kΩ or higher
    z4-6 (ANT1) - Body ground
    		Always
    		10 kΩ or higher
    z4-3 (ANT2) - Body ground
    		Always
    		10 kΩ or higher

    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to Certification ECU (Smart Key ECU Assembly))
    *2
    		Front view of wire harness connector
    (to Front Door Outside Handle Assembly (for Driver Side))
    *3
    		for LHD
    *4
    		for RHD



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


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


    B199753E29

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

    Standard Resistance:
    for LHD 
    Tester Connection
    		Condition
    		Specified Condition
    z3-2 (GND) - Body ground
    		Always
    		Below 1 Ω
    for RHD 
    Tester Connection
    		Condition
    		Specified Condition
    z4-2 (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))
    *2
    		for LHD
    *3
    		for RHD



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


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


    B203530E16

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

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    L62-15 (E) - Body ground
    		Always
    		Below 1 Ω

    Standard:
    Tester Connection
    		Condition
    		Specified Condition
    L62-3 (CLG1) - L62-15 (E)
    1. Power switch off
    2. All doors closed
    3. Key not in cabin
    		No pulse generation
    L62-3 (CLG1) - L62-15 (E)
    1. Power switch off
    2. All doors closed
    3. Key not in cabin
    4. All doors locked by wireless lock function
    		Pulse generation
    L62-4 (CG1B) - L62-15 (E)
    1. Power switch off
    2. All doors closed
    3. Key not in cabin
    		No pulse generation
    L62-4 (CG1B) - L62-15 (E)
    1. Power switch off
    2. All doors closed
    3. Key not in cabin
    4. All doors locked by wireless lock function
    		Pulse generation

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



NG
REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)
OK


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

  1. Replace the front door outside handle assembly (for driver side) (Click here).


NEXT


6.CHECK DTC OUTPUT

  1. Clear the DTCs (Click here).

  1. Recheck for DTCs.

    OK:
    DTC B27A1 is not output.



NG
REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)
OK

END (FRONT DOOR OUTSIDE HANDLE ASSEMBLY WAS DEFECTIVE)