SMART ENTRY AND START SYSTEM(for Entry Function), Diagnostic DTC:B27A8

DTC Code DTC Name
B27A8 Open in Outside Luggage Compartment Electrical Key Antenna Circuit

DESCRIPTION

The certification ECU (smart key ECU assembly) generates a request signal and transmits the signal to the electrical key antenna (outside luggage). For the electrical key antenna (outside luggage) to detect when the electrical key transmitter sub-assembly is brought close to the vehicle, the received request signal is transmitted within approximately 1.0 m (3.28 ft.) of the luggage compartment door. DTC B27A8 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 electrical key antenna (outside luggage) (between terminals CLG8 and ANTE8, or terminals CG8B and CLGB).

DTC Code DTC Detection Condition Trouble Area DTC Output Confirmation Operation
B27A8 An open circuit is detected in the circuit between the certification ECU (smart key ECU assembly) and electrical key antenna (outside luggage) (CLG8 - ANTE8, CG8B - CLGB) (1 trip detection logic*).

  • Wire harness or connector

  • Electrical key antenna (outside luggage)

  • Certification ECU (smart key ECU assembly)

 Any time

Vehicle Condition and Fail-safe Operation when Malfunction Detected
Vehicle Condition when Malfunction Detected Fail-safe Operation when Malfunction Detected
Entry unlock operation cannot be performed for luggage compartment door -
Related Data List and Active Test
DTC Code Data List and Active Test
B27A8 Key diagnostic mode can be used to perform troubleshooting

WIRING DIAGRAM

A00050YE01

CAUTION / NOTICE / HINT

Note


  • The smart 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 smart entry and start system (for Entry Function) after confirming that the communication systems are functioning properly.

  • When using the GTS with the vehicle power switch off, connect the GTS to the vehicle 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 the Model Code "KEY REGIST" under manual mode and enter the following menus: Body Electrical / Entry&Start(CAN). 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.

  • Before replacing the certification ECU (smart key ECU assembly), refer to the smart entry and start system (for Entry Function) precaution Click here.

  • After repair, confirm that no DTCs are output by performing the "DTC Output Confirmation Operation".

  • The electrical key antenna (outside luggage) has an antenna coil between ANTE8 and CLGB terminals.

PROCEDURE


  1. CHECK CONNECTOR CONNECTION


    1. Turn the power switch off.

    2. Check that the connectors are properly connected to the certification ECU (smart key ECU assembly) and electrical key antenna (outside luggage).

      OK
      Connectors are properly connected.

    NG

    CONNECT CONNECTORS PROPERLY

    OK

  2. CHECK HARNESS AND CONNECTOR (ELECTRICAL KEY ANTENNA - CERTIFICATION ECU)


    1. Disconnect the Q2 and H57 certification ECU (smart key ECU assembly) connectors.

    2. Disconnect the U10 electrical key antenna (outside luggage) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Q2-2 (CLG8) - U10-1 (ANTE8) Always Below 1 Ω
      Q2-1 (CG8B) - U10-2 (CLGB) Always Below 1 Ω
      H57-1 (E) - Body ground Always Below 1 Ω
      Q2-2 (CLG8) or U10-1 (ANTE8) - Body ground Always 10 kΩ or higher
      Q2-1 (CG8B) or U10-2 (CLGB) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. INSPECT ELECTRICAL KEY ANTENNA (OUTSIDE LUGGAGE)


    1. A000964E44
      Text in Illustration
      *a

      Component without harness connected

      (Electrical Key Antenna (Outside Luggage))

      Remove the electrical key antenna (outside luggage) Click here.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1 (ANTE8) - 2 (CLGB) Always Below 1 Ω

    NG

    REPLACE ELECTRICAL KEY ANTENNA (OUTSIDE LUGGAGE) Click here

    OK

  4. REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)


    1. Temporarily replace the certification ECU (smart key ECU assembly) with a new one.

      Tech Tips

      Refer to Service Bulletin.


    NEXT

  5. CLEAR DTC


    1. Clear the DTCs Click here.


    NEXT

  6. CHECK FOR DTC


    1. Check for DTCs Click here.

      OK
      DTC B27A8 is not output.

    OK

    END (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) WAS DEFECTIVE)

    NG

    REPLACE ELECTRICAL KEY ANTENNA (OUTSIDE LUGGAGE) Click here