Diagnostic Firewall & Diagnostic Filter

Even before SFD and SFD2 unauthorized access and/or modifications were prevented by a diagnostic firewall, which required you to open the hood prior to having full access to control module functions. We recommend to open the hood on all MY 2015 and newer before you perform any diagnostic work to ensure the diagnostic firewall is deactivated.

Newer models still have this diagnostic firewall but in addition may have diagnostic filter blocking diagnostic access to control modules entirely. VCDS uses a workaround to access these control modules but may be in Restricted (read-only) mode, preventing most advanced functions like Coding, Adaptation, Basic Settings and/or Output Test etc.

An Auto-Scan with VCDS will show you if Restricted mode is active via an addition/suffix of "-R" to the VCID line for each control module:

  Address 06: Seat Mem. Pass (J521)
  Part No SW: 1N3 959 760 H    HW: 1N3 959 760 H
  Component: MEM-BFS       011 0571
  Coding: 0118BA4000012A008803010101010000000000000000000000000000211000
  ASAM Dataset: EV_SCMPasseSideCONTIAU736 006013
  VCID: 3E2D6196D0F4264AA97-806A-R

An Auto-Scan with VCDS can show you in the VCID line combinations of "-R" and SFD and SFD2 at the same time:

  Address 08: Auto HVAC (J979)
  Part No SW: 1EE 907 007 B    HW: 1EE 907 007 B
  Component: Climatronic   H01 0146 
  Coding: 60202224A010120001100010110001102000103111101101000000000000
  ASAM Dataset: EV_ACClimaBHBE3ADV 002032
  VCID: 343943BEEEB8FC1A4F3-8060-R SFD+SFD2