ENTRY AND START SYSTEM (for Entry Function), Diagnostic DTC:B27A7

DTC Code DTC Name
B27A7 Open in Inside Luggage Compartment Electrical Key Oscillator Circuit

DESCRIPTION

The certification ECU (smart key ECU assembly) generates a request signal and sends it to the indoor electrical key oscillator (for rear floor). To detect the key inside the cabin, the indoor electrical key oscillator (for rear floor) creates a detection area in the cabin.

DTC B27A7 is detected by the certification ECU (smart key ECU assembly) when an open circuit occurs between the certification ECU (smart key ECU assembly) and indoor electrical key oscillator (for rear floor) terminals (between CLG7 and ANTE7, or CG7B and CLGB).

DTC No. DTC Detection Condition Trouble Area
B27A7 Open circuit detected between the certification ECU (smart key ECU assembly) and indoor electrical key oscillator (for rear floor) terminals (between CLG7 and ANTE7, or CG7B and CLGB).

  • Indoor electrical key oscillator (for rear floor)

  • Certification ECU (smart key ECU assembly)

  • Wire harness or connector

WIRING DIAGRAM

A0043X7E38

INSPECTION PROCEDURE

Note

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.

PROCEDURE


  1. CHECK CONNECTOR CONNECTION CONDITION


    1. Turn the power switch off.

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

      OK
      Connectors are properly connected.

    NG

    CONNECT CONNECTORS PROPERLY

    OK

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


    1. Disconnect the L56 certification ECU (smart key ECU assembly) connector.

    2. Disconnect the R20 indoor electrical key oscillator (for rear floor) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      L56-26 (CLG7) - R20-1 (ANTE7) Always Below 1 Ω
      L56-27 (CG7B) - R20-3 (CLGB) Always Below 1 Ω
      L56-26 (CLG7) - Body ground Always 10 kΩ or higher
      L56-27 (CG7B) - Body ground Always 10 kΩ or higher
      R20-1 (ANTE7) - Body ground Always 10 kΩ or higher
      R20-3 (CLGB) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

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


    1. A0042FCE59
      Text in Illustration
      *a

      Component with harness connected

      (Certification ECU (Smart Key ECU Assembly))

      Reconnect the L56 certification ECU (smart key ECU assembly) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      L56-15 (E) - Body ground Always Below 1 Ω
      Standard
      Tester Connection Condition Specified Condition
      L56-26 (CLG7) - L56-15 (E)

      • Power switch off

      • All doors closed

      • Key not in cabin

      • Door outside handle assembly (lock sensor) not touched

      		 No pulse generation
      L56-26 (CLG7) - L56-15 (E)

      • Power switch off

      • All doors closed

      • Key not in cabin

      • Door outside handle assembly (lock sensor) touched

      		 Pulse generation
      L56-27 (CG7B) - L56-15 (E)

      • Power switch off

      • All doors closed

      • Key not in cabin

      • Door outside handle assembly (lock sensor) not touched

      		 No pulse generation
      L56-27 (CG7B) - L56-15 (E)

      • Power switch off

      • All doors closed

      • Key not in cabin

      • Door outside handle assembly (lock sensor) touched

      		 Pulse generation

    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

    OK

  4. REPLACE INDOOR ELECTRICAL KEY OSCILLATOR (for Rear Floor)


    1. Replace the indoor electrical key oscillator (for rear floor) Click here.


    NEXT

  5. CHECK DTC OUTPUT


    1. Clear the DTCs Click here.

    2. Recheck for DTCs.

      OK
      DTC B27A7 is not output.

    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

    OK

    END (INDOOR ELECTRICAL KEY OSCILLATOR WAS DEFECTIVE)