PUSH-BUTTON START, 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 in the cabin, the signal from the certification ECU (smart key ECU assembly) requesting a response from the electrical key transmitter sub-assembly is transmitted inside the vehicle. 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*).

  • Certification ECU (smart key ECU assembly)

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

  • Wire harness or connector

    DTC Output Confirmation Operation:

  • Any time

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 in luggage compartment:


  • Electrical key transmitter sub-assembly locked inside vehicle

 -
Related Data List and Active Test
DTC Code Data List and Active Test
B27A7 Key diagnostic mode can be used to perform troubleshooting

WIRING DIAGRAM

A01MRHKE24

CAUTION / NOTICE / HINT

Note


  • The push-button start uses the LIN communication system and CAN communication system. Inspect the communication function by following How to Proceed with Troubleshooting. Troubleshoot the push-button start after confirming that the communication systems are functioning properly.

    Click here

  • When using the GTS with the power 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 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 push-button start Precaution.

    Click here

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

PROCEDURE


  1. CHECK CONNECTOR CONNECTION


    1. 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 (SMART KEY ECU ASSEMBLY) - NO. 1 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (INSIDE LUGGAGE))


    1. Disconnect the K7 and K8 certification ECU (smart key ECU assembly) connectors.

    2. Disconnect the Q3 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
      Tester Connection Condition Specified Condition
      K7-8 (CLG7) - Q3-1 (ANTE7) Always Below 1 Ω
      K7-7 (CG7B) - Q3-3 (CLGB) Always Below 1 Ω
      K8-1 (E) - Body ground Always Below 1 Ω
      K7-8 (CLG7) or Q3-1 (ANTE7) - Body ground Always 10 kΩ or higher
      K7-7 (CG7B) or Q3-3 (CLGB) - Body ground Always 10 kΩ or higher

    4. Reconnect the K7 and K8 certification ECU (smart key ECU assembly) connectors.

      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 (INSIDE LUGGAGE))

    A01MTLWC04
    *a

    Component with harness connected

    (Certification ECU (Smart Key ECU Assembly))

    		 *b Waveform 1
    *c Driver door lock sensor not touched *d Driver door lock sensor touched

    1. Using an oscilloscope, check the waveform.

      OK
      Tester Connection Condition Tool Setting Specified Condition
      K7-8 (CLG7) - K8-1 (E)

      Procedure:


      1. Door is closed

      2. Power switch off

      3. Electrical key transmitter sub-assembly not inside vehicle

      4. Luggage compartment door closed*

      		 2 V/DIV., 500 ms/DIV.

      Pulse generation

      (See waveform 1)
      K7-7 (CG7B) - K8-1 (E)

      Procedure:


      1. Door is closed

      2. Power switch off

      3. Electrical key transmitter sub-assembly not inside vehicle

      4. Luggage compartment door closed*

      		 2 V/DIV., 500 ms/DIV.

      Pulse generation

      (See waveform 1)

      Note

      *: In order to prevent the electrical key transmitter sub-assembly from being locked inside the vehicle, perform this inspection with the window of a door open.

      If the electrical key transmitter sub-assembly is in any of the following locations, the key lock-in prevention function may not operate:


      • Near the spare tire or at the edge of the luggage compartment.

      • In a metal bag or near a metal object.

      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 one.

      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)