SMART ENTRY AND START SYSTEM(for Entry Function), Diagnostic DTC:B27B0

DTC Code DTC Name
B27B0 Lost Communication with MainBody Module

DESCRIPTION

The certification ECU (smart key ECU assembly) and body ECU communicate using unidirectional communication lines.

This DTC is output when the certification ECU (smart key ECU assembly) sends a request to the body ECU but does not receive a reply.

DTC No. Detection Item DTC Detection Condition Trouble Area Note
B27B0 Lost Communication with MainBody Module Certification ECU (smart key ECU assembly) sends request but body ECU does not reply within 10 seconds (1 trip detection logic*).

  • Certification ECU (smart key ECU assembly)

  • Body ECU

  • Harness or connector

    DTC Output Confirmation Operation

  • Driver door open/close

*: Only output while a malfunction is present.

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

  • Entry lock/unlock operation cannot be performed

  • Wireless lock/unlock operation cannot be performed

 -
Related Data List and Active Test
DTC No. Data List and Active Test
B27B0 -

WIRING DIAGRAM

B003KIUE04
*1 Body ECU
*2 Certification ECU (Smart Key ECU Assembly)

CAUTION / NOTICE / HINT

Note


  • The smart entry and start system (for Entry Function) uses a multiplex communication system (LIN communication system) and the CAN communication system. Inspect the communication function by following How to Proceed with Troubleshooting.

    Troubleshoot the smart entry and start system (for Entry Function) after confirming that the communication systems are functioning properly.

    Click here

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

    Click here

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

  • If the body ECU has been replaced, it is necessary to initialize the body ECU.

    Click here

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - BODY ECU)


    1. Disconnect the G17 certification ECU (smart key ECU assembly) connector.

    2. Disconnect the G33 body ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G17-36 (PRG3) - G33-9 (PRG) Always Below 1 Ω
      G17-13 (RDA3) - G33-16 (RDA) Always Below 1 Ω
      G17-36 (PRG3) or G33-9 (PRG) - Body ground Always 10 kΩ or higher
      G17-13 (RDA3) or G33-16 (RDA) - Body ground Always 10 kΩ or higher

    4. Connect the G17 certification ECU (smart key ECU assembly) connector.

    5. Connect the G33 instrument panel junction block assembly (body ECU) connector.

      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  2. CLEAR DTC


    1. Clear the DTCs.

      Click here


      Body Electrical > Entry&Start > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT

  3. CHECK FOR DTC


    1. Open and close the driver door.

    2. Check for DTCs.

      Click here


      Body Electrical > Entry&Start > Trouble Codes
      OK
      DTC B27B0 is not output.
      Result
      Proceed to
      OK
      NG

    OK

    END (CONNECTOR WAS NOT CONNECTED PROPERLY)

    NG

  4. REPLACE BODY ECU


    1. Replace the body ECU with a new or known good one.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  5. CLEAR DTC


    1. Clear the DTCs.

      Click here


      Body Electrical > Combination Meter > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT

  6. CHECK FOR DTC


    1. Open and close the driver door.

    2. Check for DTCs.

      Click here


      Body Electrical > Entry&Start > Trouble Codes
      OK
      DTC B27B0 is not output.
      Result
      Proceed to
      OK
      NG

    OK

    END (BODY ECU WAS DEFECTIVE)

    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)