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Home >> Lexus >> 2020 >> UX 200 Luxury >> Repair and Diagnosis >> External Pages >> Different car >> Section 31 (Smart Access System W/ Push-Button Start (Start Function) (Diagnostic Codes & Symptom Tests (1 Of 2)) (Hybrid)) >> SMART ACCESS SYSTEM WITH PUSH-BUTTON START (for Start Function, HV Model) >> DTC B2779: Engine Starter Communication Malfunction [10/2018 - ] >> Procedure

DTC B2779: Engine Starter Communication Malfunction [10/2018 - ]: Procedure

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  1. CHECK CAN COMMUNICATION SYSTEM 
    1. Check for CAN communication system DTCs.

      Refer to DIAGNOSIS SYSTEM [10/2018 - 10/2019] Refer to DIAGNOSIS SYSTEM [10/2019 - 08/2021] Refer to DIAGNOSIS SYSTEM [08/2021 - 07/2022] Refer to DIAGNOSIS SYSTEM [07/2022 - ]

      OK

      CAN communication DTCs are not output.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    GO TO CAN COMMUNICATION SYSTEM (DIAGNOSTIC TROUBLE CODE CHART). Refer to  DIAGNOSTIC TROUBLE CODE CHART [10/2018 - ] 

    Result: 

    OK 

    See step  2

  2. READ VALUE USING TECHSTREAM (WIRELESS C CODE) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Smart Access / Data List.
    5. Read the Data List according to the display on the Techstream.

      Body Electrical > Smart Access > Data List 

      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: Remote starter ID not registered to remote engine start ECU and certification ECU (smart key ECU assembly)
      Regd: Remote starter ID registered to 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.

      Body Electrical > Smart Access > Data List 

      Tester Display
      Wireless C Code

      Result

      Result Proceed to
      "No Regd" is displayed on the Techstream A
      "Regd" is displayed on the Techstream B

    Result: 

    B 

    REPLACE REMOTE ENGINE START ECU 

    Result: 

    A 

    See step  3

  3. REGISTER REMOTE ENGINE STARTER ID 
    1. Register the remote engine starter ID.

      Result

      Proceed to
      NEXT

    Result: 

    NEXT 

    See step  4

  4. READ VALUE USING TECHSTREAM (WIRELESS C CODE) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Body Electrical / Smart Access / Data List.
    5. Read the Data List according to the display on the Techstream.

      Body Electrical > Smart Access > Data List 

      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: Remote starter ID not registered to remote engine start ECU and certification ECU (smart key ECU assembly)
      Regd: Remote starter ID registered to 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.

      Body Electrical > Smart Access > Data List 

      Tester Display
      Wireless C Code

      Result

      Result Proceed to
      "No Regd" is displayed on the Techstream A
      "Regd" is displayed on the Techstream B

    Result: 

    A 

    REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to  REMOVAL [10/2018 - 07/2022]  Refer to  REMOVAL [07/2022 - ] 

    Result: 

    B 

    REPLACE REMOTE ENGINE START ECU 

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