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 sends it to the outside electrical key oscillator (for rear side). To detect the key near the driver door, the outside electrical key oscillator (for rear side) creates a detection area towards the area approximately 1.0 m (3.28 ft.) from the back door.

DTC B27A8 is detected by the certification ECU (smart key ECU assembly) when an open circuit occurs between the certification ECU (smart key ECU assembly) and outside electrical key oscillator (for rear side) terminals (between CLG8 and CLG5, or CG8B and CLGB).

DTC No. DTC Detection Condition Trouble Area
B27A8 Open circuit detected between the certification ECU (smart key ECU assembly and outside electrical key oscillator (for rear side) terminals (between CLG8 and CLG5, or CG8B and CLGB).

  • Outside electrical key oscillator (for rear side)

  • Certification ECU (smart key ECU assembly)

  • Wire harness or connector

WIRING DIAGRAM

A01EJLHE04

INSPECTION PROCEDURE

Note


  • The smart entry and start 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 Click here. Troubleshoot the smart entry and start system (for entry function) after confirming that the communication system is functioning properly.

  • Before replacing the certification ECU (smart key ECU assembly), refer to Service Bulletin.

PROCEDURE


  1. CHECK CONNECTOR CONNECTION CONDITION


    1. Turn the engine switch off.

    2. Check that the connectors are properly connected to the certification ECU (smart key ECU assembly) and the outside electrical key oscillator (for rear side).

      OK
      Connectors are properly connected.

    NG

    CONNECT CONNECTORS PROPERLY

    OK

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


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

    2. A01EK6CE01
      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 Outside Electrical Key Oscillator (for Rear Side))

      Disconnect the outside electrical key oscillator (for rear side) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D26-19 (CLG8) - L17-1 (CLG5) Always Below 1 Ω
      D26-20 (CG8B) - L17-2 (CLGB) Always Below 1 Ω
      D26-19 (CLG8) - Body ground Always 10 kΩ or higher
      D26-20 (CG8B) - Body ground Always 10 kΩ or higher
      L17-1 (CLG5) - Body ground Always 10 kΩ or higher
      L17-2 (CLGB) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. INSPECT OUTSIDE ELECTRICAL KEY OSCILLATOR


    1. A01EJJ2E01
      Text in Illustration
      *1

      Component without harness connected

      (Outside Electrical Key Oscillator (for Rear Side))

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      L17-1 (CLG5) - L17-2 (CLGB) Always Below 1 Ω

    NG

    REPLACE OUTSIDE ELECTRICAL KEY OSCILLATOR Click here

    OK

  4. REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)


    1. Replace the certification ECU (smart key ECU assembly).

      Tech Tips

      Refer to Service Bulletin.


    NEXT

  5. CHECK DTC OUTPUT


    1. Clear the DTCs Click here.

    2. Recheck for DTCs.

      OK
      DTC B27A8 is not output.

    NG

    REPLACE OUTSIDE ELECTRICAL KEY OSCILLATOR Click here

    OK

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