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 transmits the signal to the No. 3 indoor electrical key oscillator (inside luggage). For the certification ECU (smart key ECU assembly) to detect when the key is inside the luggage compartment, the signal from the certification ECU (smart key ECU assembly) requesting a response from the key is transmitted inside the luggage compartment. DTC B27A7 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 No. 3 indoor electrical key oscillator (inside luggage) (between terminals CLG7 and ANTE7, or terminals CG7B and CLGB).

DTC No. DTC Detection Condition Trouble Area DTC Output Confirmation Operation
B27A7 An open circuit is detected in the circuit between the certification ECU (smart key ECU assembly) and No. 3 indoor electrical key oscillator (inside luggage) (CLG7 - ANTE7, CG7B - CLGB) (1 trip detection logic*1).

  • Wire harness or connector

  • No. 3 indoor electrical key oscillator (inside luggage)

  • Certification ECU (smart key ECU assembly)

 Any time*2

Vehicle Condition and Fail-safe Operation when Malfunction Detected
Vehicle Condition when Malfunction Detected Fail-safe Operation when Malfunction Detected

When key is in luggage compartment:


  • Power source mode does not change when engine switch is pressed

  • Key becomes locked inside vehicle

 -
Related Data List and Active Test
DTC No. Data List and Active Test
B27A7 Key diagnostic mode can be used to perform troubleshooting

WIRING DIAGRAM

A004J3GE92
*a Certification ECU (Smart Key ECU Assembly)
*b No. 3 Indoor Electrical Key Oscillator (Inside Luggage)

CAUTION / NOTICE / HINT

Note


  • When using the GTS with the engine switch off to troubleshoot:

    Connect the GTS to the DLC3 and turn a courtesy light switch on and off at 1.5-second intervals until communication between the GTS and vehicle begins.

  • The entry and start system (for Entry Function) uses a 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.

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

  • After repair, confirm DTC does not reoccur by performing the "DTC Output Confirmation Operation".

  • No. 3 indoor electrical key oscillator (inside luggage) has an antenna coil between CLG6 and CLGB terminals.

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 No. 3 indoor electrical key oscillator (inside luggage).

      OK
      Connectors are properly connected.

    NG

    CONNECT CONNECTORS PROPERLY

    OK

  2. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - NO. 3 INDOOR ELECTRICAL KEY OSCILLATOR)


    1. Disconnect the D40 and D48 certification ECU (smart key ECU assembly) connector.

    2. Disconnect the H9 No. 3 indoor electrical key oscillator (inside luggage) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D40-9 (CLG7) - H9-1 (ANTE7) Always Below 1 Ω
      D40-8 (CG7B) - H9-3 (CLGB) Always Below 1 Ω
      D48-11 (GND) - Body ground Always Below 1 Ω
      D40-9 (CLG7) - Body ground Always 10 kΩ or higher
      D40-8 (CG7B) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. INSPECT CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) (OUTPUT TO NO. 3 INDOOR ELECTRICAL KEY OSCILLATOR)

    A004JP2E02
    Text in Illustration
    *a

    Component with harness connected

    (Certification ECU (smart key ECU assembly))

    		 *b Waveform
    *c Within approximately 30 seconds from when the door is closed *d After approximately 30 seconds from when the door is closed

    1. Reconnect the D40 and D48 certification ECU (smart key ECU assembly) connector.

    2. Reconnect the H9 No. 3 indoor electrical key oscillator (inside luggage) connector.

    3. Using an oscilloscope, check the waveform.

      Tech Tips

      Check that the customizing "Ignition Available Area" setting of entry and start system is All Click here.

      OK
      Tester Connection Switch Condition Tool Setting Specified Condition
      D40-9 (CLG7) - D48-11 (GND)

      Procedure:


      1. Engine switch off

      2. Door is open

      3. Door is closed

      4. 30 seconds elapse

      5. Electrical key transmitter not inside vehicle

      		 2 V/DIV., 500 ms/DIV.

      Pulse generation

      (See waveform)
      D40-8 (CG7B) - D48-11 (GND)

      Procedure:


      1. Engine switch off

      2. Door is open

      3. Door is closed

      4. 30 seconds elapse

      5. Electrical key transmitter not inside vehicle

      		 2 V/DIV., 500 ms/DIV.

      Pulse generation

      (See waveform)

    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

    OK

  4. REPLACE NO. 3 INDOOR ELECTRICAL KEY OSCILLATOR (INSIDE LUGGAGE)


    1. Temporarily replace the No. 3 indoor electrical key oscillator (inside luggage) with a new or normally functioning one Click here.


    NEXT

  5. CHECK DTC OUTPUT


    1. Clear the DTCs Click here.

    2. Recheck for DTCs Click here.

      OK
      B27A7 is not output.

    OK

    END (NO. 3 INDOOR ELECTRICAL KEY OSCILLATOR WAS DEFECTIVE)

    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)