REMOTE ENGINE STARTER 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 engine, 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, this DTC is cleared.

DTC Code DTC Detection Condition Trouble Area
B2779

Either of the following conditions is met:


  • A remote start communication error occurs.

  • Response is not possible.

  • Remote engine starter ECU

  • Wire harness or connector

  • Main body ECU (multiplex network body ECU)

  • Certification ECU (smart key ECU assembly)

WIRING DIAGRAM

A01HPW5E04

INSPECTION PROCEDURE

Note


  • 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 remote engine starter ECU, refer to Registration of the remote engine starter system Click here.

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

  • The remote engine starter system uses the CAN communication system. Inspect the communication function by following How to Proceed with Troubleshooting Click here. Troubleshoot the remote engine starter system after confirming that the communication systems are functioning properly.

PROCEDURE


  1. CHECK DTC OUTPUT


    1. Clear the DTC Click here.

    2. Perform the remote engine start operation.

    3. Check for DTCs.

      OK
      DTC B126A is not output.

    NG

    GO TO OTHER FLOW CHART (B126A) Click here

    OK

  2. READ VALUE USING TECHSTREAM


    1. Turn the engine switch off.

    2. Connect the Techstream to the DLC3.

    3. Turn the engine 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)

      		 -
      Result
      Result Proceed to
      "No Regd" appears on the Techstream screen A
      "Regd" appears on the Techstream screen B

    B

    CHECK HARNESS AND CONNECTOR (REMOTE ENGINE STARTER ECU - BATTERY AND BODY GROUND) Click here

    A

  3. REGISTER REMOTE ENGINE STARTER ID


    1. Register the remote engine starter ID Click here.


    NEXT

  4. CHECK DTC OUTPUT


    1. Clear the DTC Click here.

    2. Perform the remote engine start operation.

    3. Check for DTCs.

      OK
      DTC B2779 is not output.

    NG

    REPLACE REMOTE ENGINE STARTER ECU Click here

    OK

    END (REMOTE ENGINE STARTER ID WAS NOT REGISTERED CORRECTLY)

  5. CHECK HARNESS AND CONNECTOR (REMOTE ENGINE STARTER ECU - BATTERY AND BODY GROUND)


    1. Disconnect the I141 remote engine starter ECU connector.

    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      I141-10 (R+B) - Body ground Always 11 to 14 V
      I141-1 (RSIG) - Body ground Engine switch on (IG) 11 to 14 V
      I141-1 (RSIG) - Body ground Engine switch off Below 1 V
      Standard Resistance
      Tester Connection Condition Specified Condition
      I141-19 (RGN1) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) - REMOTE ENGINE STARTER ECU)


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

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      I13-25 (BTX) - I141-4 (BTX) Always Below 1 Ω
      I13-26 (BRX) - I141-3 (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

  7. REPLACE REMOTE ENGINE STARTER ECU


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


    NEXT

  8. REGISTER REMOTE ENGINE STARTER ID


    1. Register the remote engine starter ID Click here.


    NEXT

  9. CHECK DTC OUTPUT


    1. Clear the DTC Click here.

    2. Perform the remote engine start operation.

    3. Check for DTCs.

      OK
      DTC B2779 is not output.

    NG

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

    OK

    END (REMOTE ENGINE STARTER ECU WAS DEFECTIVE)

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


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


    NEXT

  11. CHECK DTC OUTPUT


    1. Clear the DTC Click here.

    2. Perform the remote engine start operation.

    3. Check for DTCs.

      OK
      DTC B2779 is not output.

    NG

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) Click here

    OK

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