ENTRY AND START SYSTEM (for Entry Function), Diagnostic DTC:B27A5

DTC Code DTC Name
B27A5 Open in Front Floor Electrical Key Oscillator Circuit

DESCRIPTION

The certification ECU generates a request signal and transmits the signal to the indoor No. 1 electrical key antenna (front floor). The indoor No. 1 electrical key antenna (front floor) detects that the electrical key is inside the vehicle and transmits the request signal received from the certification ECU. DTC B27A5 is stored by the certification ECU when an open circuit is detected in the circuit between the certification ECU and indoor No. 1 electrical key antenna (front floor) (CLG5 - CLG3, CG5B - CLGB).

DTC Code DTC Detection Condition Trouble Area
B27A5 An open circuit is detected in the circuit between the certification ECU and indoor No. 1 electrical key antenna (front floor) (CLG5 - CLG3, CG5B - CLGB).

  • Harness or connector

  • Indoor No. 1 electrical key antenna (front floor)

  • Certification ECU

WIRING DIAGRAM

A00953NE13

INSPECTION PROCEDURE

Note


  • 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.

  • When using the intelligent tester with the engine 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.

  • Before replacing the certification ECU, refer to the Service Bulletin.

PROCEDURE


  1. CHECK CONNECTOR CONNECTION


    1. Turn the engine switch off.

    2. Check that the connectors are properly connected to the certification ECU and indoor No. 1 electrical key antenna (front floor).

      OK
      Connectors are properly connected.

    NG

    CONNECT CONNECTORS PROPERLY

    OK

  2. CHECK HARNESS AND CONNECTOR (INDOOR NO. 1 ELECTRICAL KEY ANTENNA - CERTIFICATION ECU)


    1. Disconnect the i1 antenna connector.

    2. Disconnect the G38 ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      i1-1 (CLG3) - G38-7 (CLG5) Always Below 1 Ω
      i1-3 (CLGB) - G38-8 (CG5B) Always Below 1 Ω
      G38-7 (CLG5) - Body ground Always 10 kΩ or higher
      G38-8 (CG5B) - Body ground Always 10 kΩ or higher
      G38-15 (E) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK CERTIFICATION ECU


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

      A009BGKE17
      Text in Illustration
      *a

      Component with harness connected

      (Certification ECU)

      		 - -
      OK
      Tester Connection Switch Condition Specified Condition
      G38-7 (CLG5) - G38-15 (E) Engine switch off, all doors closed, key not in cabin and lock sensor off → on No pulse generation → Pulse generation
      G38-8 (CG5B) - G38-15 (E) Engine switch off, all doors closed, key not in cabin and lock sensor off → on No pulse generation → Pulse generation

    NG

    REPLACE CERTIFICATION ECU

    OK

  4. REPLACE INDOOR NO. 1 ELECTRICAL KEY ANTENNA ASSEMBLY (FRONT FLOOR)


    1. Temporarily replace the indoor No. 1 electrical key antenna (front floor) with a new or normally functioning one Click here.


    NEXT

  5. CHECK FOR DTC


    1. Clear the DTCs Click here.

    2. Check for DTCs Click here.

      OK
      DTC B27A5 is not output.

    NG

    REPLACE CERTIFICATION ECU

    OK

    END (INDOOR NO. 1 ELECTRICAL KEY ANTENNA ASSEMBLY IS DEFECTIVE)