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 transmits the signal to the front door outside handle assembly (for driver door) [electrical key antenna] at intervals of 250 ms. For the front door outside handle assembly (for driver door) [electrical key antenna] to detect when the key is brought close to the vehicle, a signal requesting a response from the key is transmitted within approximately 1 m (3.28 ft.) of the driver door at intervals of 250 ms. DTC B27A1 is stored by the certification ECU (smart key ECU assembly) when an open circuit is detected between the certification ECU (smart key ECU assembly) and front door outside handle assembly (for driver door) [electrical key antenna] (between terminals CLG1 and ANT1, or terminals CG1B and ANT2).

DTC Code
DTC Detection Condition
Trouble Area
DTC Output Confirmation Operation
B27A1
An open circuit is detected in the circuit between the certification ECU (smart key ECU assembly) and front door outside handle 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*).
  1. Harness or connector
  2. Front door outside handle assembly (for driver door)
  3. Certification ECU (smart key ECU assembly)
Any time
  1. *: 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 Code
Data List and Active Test
B27A1
Key diagnostic mode can be used to perform troubleshooting

WIRING DIAGRAM


B249951E46


INSPECTION PROCEDURE

NOTICE:
  1. The entry and start system (for Entry Function) uses a multiplex communication system (LIN communication system) and the 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 systems are functioning properly.
  2. When using the intelligent tester with the power switch off to troubleshoot:
    Connect the intelligent tester to the DLC3 and turn a courtesy light switch on and off at 1.5-second intervals until communication between the intelligent tester and vehicle begins.
  3. Before replacing the certification ECU (smart key ECU assembly), refer to the entry and start system (for Entry Function) (Click here).
  4. After repair, confirm DTC not reoccur with performing the "DTC Output Confirmation Operation".
  5. Front door outside handle assembly (for driver door) has an antenna coil between ANT1 and ANT2 terminals.

1.CHECK CONNECTOR CONNECTION

  1. Turn the power switch off.

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

    OK:
    Connectors are properly connected.



NG
CONNECT CONNECTORS PROPERLY
OK


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

  1. Disconnect the H1 certification ECU (smart key ECU assembly) connector.

  1. Disconnect the O1*1, N1*2 front door outside handle assembly (for driver door) connector.

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

    1. *1: for LHD
    2. *2: for RHD

    Standard Resistance:
    for LHD 
    Tester Connection
    		Condition
    		Specified Condition
    H1-3 (CLG1) - O1-6 (ANT1)
    		Always
    		Below 1 Ω
    H1-4 (CG1B) - O1-3 (ANT2)
    		Always
    		Below 1 Ω
    H1-15 (E) - Body ground
    		Always
    		Below 1 Ω
    O1-2 (GND) - Body ground
    		Always
    		Below 1 Ω
    H1-3 (CLG1) or O1-6 (ANT1) - Body ground
    		Always
    		10 kΩ or higher
    H1-4 (CG1B) or O1-3 (ANT2) - Body ground
    		Always
    		10 kΩ or higher
    for RHD 
    Tester Connection
    		Condition
    		Specified Condition
    H1-3 (CLG1) - N1-6 (ANT1)
    		Always
    		Below 1 Ω
    H1-4 (CG1B) - N1-3 (ANT2)
    		Always
    		Below 1 Ω
    H1-15 (E) - Body ground
    		Always
    		Below 1 Ω
    N1-2 (GND) - Body ground
    		Always
    		Below 1 Ω
    H1-3 (CLG1) or N1-6 (ANT1) - Body ground
    		Always
    		10 kΩ or higher
    H1-4 (CG1B) or N1-3 (ANT2) - Body ground
    		Always
    		10 kΩ or higher



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


3.CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) (OUTPUT TO DRIVER SIDE ELECTRICAL KEY ANTENNA)


  1. Connect the H1 certification ECU (smart key ECU assembly) connector.


    B249957E18


    Text in Illustration 
    *1
    		Waveform 1
    		*2
    		Waveform 2
    *a
    		Component with harness connected
    (Certification ECU (Smart Key ECU Assembly))
    		-
    		-

  1. Connect the O1*1, N1*2 front door outside handle assembly (for driver door) connector.

  1. Using an oscilloscope, check the waveform.

    OK:

    Tester Connection
    		Switch Condition
    		Tool Setting
    		Specified Condition
    H1-3 (CLG1) - H1-15 (E)
    		Procedure:
    1. Power switch off
    2. Key brought outside vehicle
    3. All doors closed
    4. Key not inside vehicle
    5. Key brought inside detection area*3
    6. All doors locked through wireless operation
    		2 V/DIV., 500 ms/DIV.
    		Pulse generation (See waveform 1)
    H1-3 (CLG1) - H1-15 (E)
    		Procedure:
    1. Power switch off
    2. Key brought outside vehicle
    3. All doors closed
    4. Key not inside vehicle
    5. Key brought outside detection area*4
    6. All doors locked through wireless operation
    		2 V/DIV., 500 ms/DIV.
    		Pulse generation (See waveform 2)
    H1-4 (CG1B) - H1-15 (E)
    		Procedure:
    1. Power switch off
    2. Key brought outside vehicle
    3. All doors closed
    4. Key not inside vehicle
    5. Key brought outside detection area*4
    6. All doors locked with key
    		2 V/DIV., 500 ms/DIV.
    		Pulse generation (See waveform 2)

    1. *1: for LHD
    2. *2: for RHD
    3. *3: For details about the areas that are inside the entry function detection area, refer to Operation Check (Click here).
    4. *4: For details about the areas that are outside the entry function detection area, refer to Operation Check (Click here).



NG
REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)
OK


4.REPLACE FRONT DOOR OUTSIDE HANDLE ASSEMBLY (FOR DRIVER DOOR)

  1. Temporarily replace the front door outside handle assembly (for driver door) with a new or normally functioning one (Click here).


NEXT


5.CLEAR DTC

  1. Clear the DTCs (Click here).


NEXT


6.CHECK FOR DTC

  1. Check for DTCs (Click here).

    OK:
    DTC B27A1 is not output.



NG
REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)
OK

END (FRONT DOOR OUTSIDE HANDLE ASSEMBLY WAS DEFECTIVE)