Audi S6 Central Locking System Complete Failure Fix

Based on experience with a 2009 Audi S4 (4.2L), this central locking issue typically stems from faulty wiring connections at the control module. The keyless entry system stopped working completely, showing similar symptoms. The locking mechanism failure often starts with the driver door and spreads to other doors. In most cases, the issue traces back to three common causes: 1. Damaged wiring harness between door and body 2. Failed central locking control module 3. Corroded plug connections at the module For the S6 model, the control module sits behind the fuse box in the driver side footwell. When water seeps into this area, it can damage both the module and its connections. The repair requires: Full diagnostic scan, Removal of door panels, Testing all door lock actuators, Inspecting wire harness integrity, Possibly replacing the control module This qualifies as a serious electrical system issue since it affects vehicle security. The car alarm system may also behave erratically due to the same failing components. A proper fix involves more than just replacing parts, careful inspection of all wiring and connections is essential to prevent future failures.

Thanks for sharing those details about the wiring harness and control module issues. I had exactly the same problem with my Audi S6 last summer. The security system kept throwing codes and the key fob stopped working completely. After finding moisture damage in the locking mechanism, they had to replace both the control unit and some corroded wiring. Just wondering, did you end up getting yours fixed? What was the final repair cost? My fix was quite expensive but I am curious if prices vary. Also, have you noticed any other electrical gremlins since the repair? Sometimes these fuse box area problems can cascade into other issues.

Yes, got my central locking issue fully resolved last month. The mechanic found a damaged cable connection at the control module near the fuse box, which was causing the keyless entry system to fail. Much simpler fix than initially feared, no need to replace the entire control unit. The repair cost came to 95 Euro for fixing the faulty wiring connection. This included testing the security system to ensure all doors were responding properly to the key fob. Since the repair, the central locking works perfectly with no electrical issues. The key fob communication is reliable again, and the security system no longer shows any error codes. Always worth getting a thorough diagnosis, sometimes these problems have simple solutions despite seeming major at first. Much better outcome than facing a complete control module replacement. Regular checks of the fuse box area for moisture can help prevent similar issues from developing.

I took my S6 to the mechanic last week after reading these responses. They found severe water damage around the control module, exactly as described. The locking mechanism was completely corroded, and the security system showed multiple error codes. The repair involved: Replacing the central control module, Installing new wiring harness, Fixing door lock actuators, Updating system software Total cost came to 780 Euro, which was actually less than the previous quote. The keyless entry now works perfectly, and all doors respond to the key fob. No error codes since the fix. What really helped was knowing about the common failure points before going in. They initially suggested replacing all door locks, but I pushed them to check the control module area first. Saved quite a bit by targeting the actual problem. Next step is waterproofing the fuse box area to prevent future issues. Not taking any chances with moisture damaging the new components.