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DTC B2785: Communication Malfunction between ECUs Connected by LIN [04/2013 - 09/2022]: Description

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The certification ECU (smart key ECU assembly) monitors communication between all the ECUs connected to the certification bus lines. When the certification ECU (smart key ECU assembly) detects errors in communication with all the ECUs connected to the certification bus lines at a set interval and 3 times in a row, DTC B2785 will be stored.

DTC No. Detection Item DTC Detection Condition Trouble Area
B2785 Communication Malfunction between ECUs Connected by LIN
  • Errors in LIN communication between ECUs or an open or short in communication lines.
  • LIN communication error detected by the certification ECU (smart key ECU assembly) 3 times in a row.
  • Certification ECU (smart key ECU assembly)
  • Steering lock ECU (steering lock actuator assembly)
  • ID code box (immobiliser code ECU)
  • Wire harness or connector
  • STRG LOCK fuse
  • SMART fuse