ENGINE IMMOBILISER SYSTEM, Diagnostic DTC:B2779

DTC Code DTC Name
B2779 Engine Starter Communication Malfunction

DESCRIPTION

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

When the remote engine starter ECU does not respond to the certification ECU (smart key ECU assembly), this DTC is stored. When communication with the remote engine starter ECU is established and a remote engine start operation is performed, 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 engine start communication error occurs.

  • Response is not possible.

  • Registration has not been performed.

  • Remote engine starter ECU

  • Wire harness or connector

  • Main body ECU (multiplex network body ECU)

  • Certification ECU (smart key ECU assembly)

 A remote engine start operation is performed.
Vehicle Condition and Fail-safe Operation when Malfunction Detected
Vehicle Condition when Malfunction Detected Fail-safe Operation when Malfunction Detected
Hybrid control system does not start with remote engine start operation Hybrid control system cannot be started by remote engine 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

A011YD6E02

INSPECTION PROCEDURE

Note

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

  • Before replacing the certification ECU (smart key ECU assembly), refer to Registration Click here.

  • 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 TECHSTREAM

    1. Turn the power switch off.

    2. Connect the Techstream to the DLC3.

    3. Turn the power switch on (IG).

    4. Turn the Techstream on.

    5. Enter the following menus: Body Electrical / Smart Key / Data List.

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

      Smart Key (Certification ECU (Smart Key ECU Assembly))
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Wireless C Code Registration status between remote engine starter ECU and certification ECU (smart key ECU assembly)/No Regd or Regd

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

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

      Problems may be caused by the following:

      • Remote engine starter ECU registration has not been performed.

      • Malfunctions in the certification ECU (smart key ECU assembly) or remote engine starter 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 ENGINE START ID

    1. Register the remote engine start ID.

    NEXT

  3. CHECK REMOTE ENGINE START

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

      OK
      Hybrid control system can be started using remote engine start operation.
    NG

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

    OK

    END (REMOTE ENGINE 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 (multiplex network body ECU) and option connector are listed.

    1. Disconnect the I13 main body ECU (multiplex network body ECU) connector.

    2. Disconnect the I89 option connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      I13-25 (BTX) - I89-4 (BTX) Always Below 1 Ω
      I13-26 (BRX) - I89-8 (BRX) Always Below 1 Ω
      I13-25 (BTX) - Body ground Always 10 kΩ or higher
      I13-26 (BRX) - Body ground Always 10 kΩ or higher
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. REPLACE REMOTE ENGINE STARTER ECU

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

    2. Register the remote engine start ID.

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

      OK
      Hybrid control system can be started using remote engine start operation.
    NG

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

    OK

    END (REMOTE ENGINE STARTER ECU WAS DEFECTIVE)

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

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

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

      OK
      Hybrid control system can be started using remote engine start operation.
    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) Click here

    OK

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