ENTRY AND START SYSTEM(for Entry Function), Diagnostic DTC:B27A5

DTC Code DTC Name
B27A5 Open in Front Floor Electrical Key Oscillator Circuit

DESCRIPTION

The certification ECU (smart key ECU assembly) generates a request signal and transmits the signal to the No. 2 indoor electrical key antenna assembly (front floor). For the No. 2 indoor electrical key antenna assembly (front floor) 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 B27A5 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. 2 indoor electrical key antenna assembly (front floor) (between terminals CLG5 and ANTE5, or terminals CG5B and CLGB).

DTC No. Detection Item DTC Detection Condition Trouble Area Note
B27A5 Open in Front Floor Electrical Key Oscillator Circuit An open circuit is detected in the circuit between the certification ECU (smart key ECU assembly) and No. 2 indoor electrical key antenna assembly (front floor) (CLG5 - ANTE5, CG5B - CLGB) (1 trip detection logic*).
  • Certification ECU (smart key ECU assembly)

  • No. 2 indoor electrical key antenna assembly (front floor)

  • 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 front seat area:


  • Power source mode does not change when power switch pressed

  • Electrical key transmitter sub-assembly locked inside vehicle

-
Related Data List and Active Test
DTC Code Data List and Active Test
B27A5 Key diagnostic mode can be used to perform troubleshooting

WIRING DIAGRAM

A0021BME03

CAUTION / NOTICE / HINT

Note


  • The entry and start system (for Entry Function) uses the LIN communication system and CAN communication system. Inspect the communication function 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 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 entry and start system (for Entry Function) 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. 2 indoor electrical key antenna assembly (front floor).

      OK
      Connectors are properly connected.
      Result
      Proceed to
      OK
      NG

    NG
    OK
  2. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - NO. 2 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (FRONT FLOOR))


    1. Disconnect the K137 certification ECU (smart key ECU assembly) connector.

    2. Disconnect the K87 No. 2 indoor electrical key antenna assembly (front floor) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      K137-21 (CLG5) - K87-1 (ANTE5) Always Below 1 Ω
      K137-20 (CG5B) - K87-3 (CLGB) Always Below 1 Ω
      K137-11 (E) - Body ground Always Below 1 Ω
      K137-21 (CLG5) or K87-1 (ANTE5) - Body ground Always 10 kΩ or higher
      K137-20 (CG5B) or K87-3 (CLGB) - Body ground Always 10 kΩ or higher
    4. Reconnect the K137 certification ECU (smart key ECU assembly) connector.

      Result
      Proceed to
      OK
      NG

    NG
    OK
  3. CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) (OUTPUT TO NO. 2 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (FRONT FLOOR))

    A0022QTC76
    *a

    Component with harness connected

    (Certification ECU (Smart Key ECU Assembly))

    *b Waveform 1
    *c For 30 seconds after closing any door using the door outside handle *d 30 seconds or more have elapsed after closing any door using the door outside handle

    1. Using an oscilloscope, check the waveform.

      OK
      Tester Connection Condition Tool Setting Specified Condition
      K137-21 (CLG5) - K137-11 (E)

      Procedure:


      1. Power switch off

      2. Electrical key transmitter sub-assembly not inside vehicle

      3. Within 30 seconds of closing any door using the door outside handle

      2 V/DIV., 500 ms/DIV.

      Pulse generation

      (See waveform 1)

      K137-20 (CG5B) - K137-11 (E)

      Procedure:


      1. Power switch off

      2. Electrical key transmitter sub-assembly not inside vehicle

      3. Within 30 seconds of closing any door using the door outside handle

      2 V/DIV., 500 ms/DIV.

      Pulse generation

      (See waveform 1)

      Result
      Proceed to
      OK
      NG

    NG
    OK
  4. REPLACE NO. 2 INDOOR ELECTRICAL KEY ANTENNA ASSEMBLY (FRONT FLOOR)


    1. Temporarily replace the No. 2 indoor electrical key antenna assembly (front floor) 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 B27A5 is not output.
      Result
      Proceed to
      OK
      NG

    OK
    NG