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. 1 indoor electrical key antenna assembly (inside luggage). For the No. 1 indoor electrical key antenna assembly (inside luggage) to detect when the electrical key transmitter sub-assembly is inside the luggage area, the signal from the certification ECU (smart key ECU assembly) requesting a response from the electrical key transmitter sub-assembly 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. 1 indoor electrical key antenna assembly (inside luggage) (between terminals CLG7 and ANTE7, or terminals CG7B and CLGB).

DTC NO.

Detection Item

DTC Detection Condition

Trouble Area

Note

B27A7

Open in Inside Luggage Compartment Electrical Key Oscillator Circuit

An open circuit is detected in the circuit between the certification ECU (smart key ECU assembly) and No. 1 indoor electrical key antenna assembly (inside luggage) (CLG7 - ANTE7, CG7B - CLGB) (1 trip detection logic*).

  • Wire harness or connector

  • No. 1 indoor electrical key antenna assembly (inside luggage)

  • Certification ECU (smart key ECU assembly)

  • DTC Output Confirmation Operation

  • Any time

  • *: Only output while a malfunction is present.

Table 1. Vehicle Condition and Fail-safe Operation when Malfunction Detected

Vehicle Condition when Malfunction Detected

Fail-safe Operation when Malfunction Detected

When electrical key transmitter sub-assembly is inside luggage area:

  • Power Source mode does not change when engine switch pressed (except Sedan)

  • Electrical key transmitter sub-assembly locked inside vehicle

-
Table 2. Related Data List and Active Test Item

DTC Code

Data List and Active Test Item

B27A7

Key diagnostic mode can be used to perform troubleshooting

WIRING DIAGRAM

B320942E69

CAUTION / NOTICE / HINT

Note:

  • The entry and start system (for Entry Function) uses the CAN communication system and LIN communication system. First inspect the communication systems by following How to Proceed with Troubleshooting. Troubleshoot the entry and start system (for Entry Function) after confirming that the communication systems are functioning properly.

    Click hereClick here

  • When using the GTS with the engine switch off, connect the GTS to the DLC3 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 entry and start system (for Entry Function) Precaution.

    Click here

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

  • The No. 1 indoor electrical key antenna assembly (inside luggage) has an antenna coil between terminals ANTE7 and CLGB.

PROCEDURE

  1. CHECK CONNECTOR CONNECTION

    1. Turn the engine switch off.

    2. Check that the connectors are properly connected to the certification ECU (smart key ECU assembly) and No. 1 indoor electrical key antenna assembly (inside luggage).

      OK

      Connectors are properly connected.

    Result

    Proceed to

    OK

    NG
    NG

    CONNECT CONNECTORS PROPERLY

    OK

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

    1. Disconnect the E34 and E33 certification ECU (smart key ECU assembly) connectors.

    2. Disconnect the M2*1 or L85*2 No. 1 indoor electrical key antenna assembly (inside luggage) connector.

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

      Standard Resistance

      except Sedan

      Tester Connection

      Condition

      Specified Condition

      E34-9 (CLG7) - M2-1 (ANTE7)

      Always

      Below 1 Ω

      E34-8 (CG7B) - M2-3 (CLGB)

      Always

      Below 1 Ω

      E33-11 (E) - Body ground

      Always

      Below 1 Ω

      E34-9 (CLG7) or M2-1 (ANTE7) - Body ground

      Always

      10 kΩ or higher

      E34-8 (CG7B) or M2-3 (CLGB) - Body ground

      Always

      10 kΩ or higher

      Standard Resistance

      for Sedan

      Tester Connection

      Condition

      Specified Condition

      E34-9 (CLG7) - L85-1 (ANTE7)

      Always

      Below 1 Ω

      E34-8 (CG7B) - L85-3 (CLGB)

      Always

      Below 1 Ω

      E33-11 (E) - Body ground

      Always

      Below 1 Ω

      E34-9 (CLG7) or L85-1 (ANTE7) - Body ground

      Always

      10 kΩ or higher

      E34-8 (CG7B) or L85-3 (CLGB) - Body ground

      Always

      10 kΩ or higher

    • *1: except Sedan

    • *2: for Sedan

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) (OUTPUT TO NO. 1 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY)

    1. Connect the E33 and E34 certification ECU (smart key ECU assembly) connectors.

      B318537C02

      *A

      except Sedan

      *B

      for Sedan

      *a

      Component with harness connected

      (Certification ECU (Smart Key ECU Assembly))

      *b

      Waveform 1

      *c

      Waveform 2

      *d

      Door open

      *e

      Approximately 30 seconds after door closed

      *f

      Before driver door lock sensor touched

      *g

      After driver door lock sensor touched

      -

      -

    2. Connect the M2*1 or L85*2 No. 1 indoor electrical key antenna assembly (inside luggage) connector.

      • *1: except Sedan

      • *2: for Sedan

    3. Using an oscilloscope, check the waveform.

      OK (except Sedan)

      Tester Connection

      Condition

      Tool Setting

      Specified Condition

      E34-9 (CLG7) - E33-11 (E)

      Procedure:

      1. Engine switch off

      2. Electrical key transmitter sub-assembly not inside vehicle

      3. Door is open

      4. Door is closed

      5. Within 30 seconds

      2 V/DIV., 500 ms/DIV.

      Pulse generation

      (See waveform)

      E34-8 (CG7B) - E33-11 (E)

      Procedure:

      1. Engine switch off

      2. Electrical key transmitter sub-assembly not inside vehicle

      3. Door is open

      4. Door is closed

      5. Within 30 seconds

      2 V/DIV., 500 ms/DIV.

      Pulse generation

      (See waveform)

      OK (for Sedan)

      Tester Connection

      Condition

      Tool Setting

      Specified Condition

      E34-9 (CLG7) - E33-11 (E)

      Procedure:

      1. Engine switch off

      2. Electrical key transmitter sub-assembly not inside vehicle

      3. All doors closed

      4. Driver door lock sensor not touched → touched

      2 V/DIV., 500 ms/DIV.

      Pulse generation

      (See waveform 2)

      E34-8 (CG7B) - E33-11 (E)

      Procedure:

      1. Engine switch off

      2. Electrical key transmitter sub-assembly not inside vehicle

      3. All doors closed

      4. Driver door lock sensor not touched → touched

      2 V/DIV., 500 ms/DIV.

      Pulse generation

      (See waveform 2)

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

    OK

  4. REPLACE NO. 1 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (INSIDE LUGGAGE)

    1. Temporarily replace the No. 1 indoor electrical key antenna assembly (inside luggage) with a new or known good one.

      for Hatchback:Click here

      for Sedan:Click here

      for Wagon:Click here

    Result

    Proceed to

    NEXT
    NEXT

  5. CLEAR DTC

    1. Clear the DTCs.

      Body Electrical > Entry&Start > Clear DTCs

    Result

    Proceed to

    NEXT
    NEXT

  6. CHECK FOR DTC

    1. Check for DTCs.

      Body Electrical > Entry&Start > Trouble Codes

      OK

      DTC B27A7 is not output.

    Result

    Proceed to

    OK

    NG
    OK

    END (NO. 1 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (INSIDE LUGGAGE) WAS DEFECTIVE)

    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)