IMMOBILISER SYSTEM, Diagnostic DTC:B2779

DTC Code DTC Name
B2779 Engine Starter Communication Malfunction

DESCRIPTION

If communication between the remote engine start ECU and certification ECU (smart key ECU assembly) cannot be performed even if a remote start operation is performed to try changing the power source mode to on (IG) or start the engine, this DTC is stored.

When the remote engine start ECU does not respond to the certification ECU (smart key ECU assembly), this DTC is stored. When communication with the remote engine start ECU is established, this DTC is cleared.

DTC Code DTC Detection Condition Trouble Area DTC Output Confirmation Operation
B2779

One of the following conditions is met (1 trip detection logic*):


  • A remote start communication error occurs.

  • Response is not possible.

  • Registration has not been performed.

  • Remote engine start ECU

  • Wire harness or connector

  • Main body ECU (multiplex network body ECU)

  • Certification ECU (smart key ECU assembly)

 A remote start operation is performed.

Vehicle Condition and Fail-safe Operation when Malfunction Detected
Vehicle Condition when Malfunction Detected Fail-safe Operation when Malfunction Detected
Engine does not start with remote start operation Engine cannot be started by remote start operation only
Related Data List and Active Test
DTC Code Data List and Active Test
B2779

  • Wireless Starter Com ID

  • Wireless C Code

WIRING DIAGRAM

A01G5DBE08

INSPECTION PROCEDURE

Note


  • 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.

  • Inspect the fuses for circuits related to this system before performing the following inspection procedure.

  • Before performing the inspection, check that DTC U0142 is not output.

  • Before replacing the certification ECU (smart key ECU assembly) or main body ECU (multiplex network body ECU), refer to Service Bulletin.

  • After performing repair, perform the operation that fulfills the DTC output confirmation operation, and then confirm that no DTCs are output again.

Tech Tips

In this repair manual, only the terminal numbers used for inspection between the main body ECU (multiplex network body ECU) and option connector are listed.

PROCEDURE


  1. READ VALUE USING GTS (WIRELESS C CODE)


    1. Turn the engine switch off.

    2. Connect the GTS to the DLC3.

    3. Turn the engine switch on (IG).

    4. Turn the GTS on.

    5. Enter the following menus: Body Electrical / Entry&Start / Data List.

    6. According to the display on the GTS, read the Data List.

      Entry&Start
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Wireless C Code Registration status between remote engine start ECU and certification ECU (smart key ECU assembly) / No Regd or Regd

      No Regd: ID not registered between remote engine start ECU and certification ECU (smart key ECU assembly)

      Regd: ID registered between remote engine start ECU and certification ECU (smart key ECU assembly)

      Problems may be caused by the following:


      • DTC B2779 is stored.

      • Remote engine start ECU registration has not been performed.

      • Malfunctions in the certification ECU (smart key ECU assembly) or remote engine start ECU.
      OK
      "Regd" appears on the screen.
      Result
      Result Proceed to
      "No Regd" appears on the screen A
      "Regd" appears on the screen B

    B

    CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - OPTION CONNECTOR) Click here

    A

  2. REGISTER REMOTE START ID


    1. Register the remote start ID.


    NEXT

  3. CHECK REMOTE START OPERATION


    1. Check that the engine can be started using remote start operation.

      OK
      Engine can be started using remote start operation.

    NG

    CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - OPTION CONNECTOR) Click here

    OK

    END (REMOTE START ID WAS NOT REGISTERED CORRECTLY)

  4. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - OPTION CONNECTOR)

    Tech Tips

    In this repair manual, only the terminal numbers used for inspection between the main body ECU and option connector are listed.


    1. Disconnect the H10 main body ECU (multiplex network body ECU) connector.

    2. Disconnect the H151 option connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H10-25 (BTX) - H151-7 (BTX) Always Below 1 Ω
      H10-26 (BRX) - H151-3 (BRX)
      H10-25 (BTX) - Body ground Always 10 kΩ or higher
      H10-26 (BRX) - Body ground

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK REMOTE ENGINE START ECU


    1. Temporarily replace the remote engine start ECU with a new one.

    2. Register the remote start ID.

    3. Check that the engine can be started using remote start operation.

      OK
      Engine can be started using remote start operation.

    NG

    CHECK MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here

    OK

    END (REMOTE ENGINE START ECU WAS DEFECTIVE)

  6. CHECK MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)


    1. Temporarily replace the main body ECU (multiplex network body ECU) with a new one Click here.

    2. Check that the engine can be started using remote start operation.

      OK
      Engine can be started using remote start operation.

    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)

    OK

    END (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) WAS DEFECTIVE)