Audi S8 Door Lock Failure: Fix Guide & Common Causes

I had a similar electrical issue with my 2012 Audi S6, which shares many components with the S8 platform. I have some experience working on basic car maintenance but electrical issues are trickier. The main problem turned out to be a faulty wiring harness connection at the door latch mechanism. The door switch was receiving inconsistent signals due to a loose connector that had worked its way free over time. The workshop found the issue during diagnostics of the door electrical system. The fix involved reconnecting and securing the wiring harness to the door latch assembly properly. Total cost was 95 Euro including diagnostic time. Since the repair, all door functions have worked perfectly. To help troubleshoot your specific case better, could you provide: Does this affect all vehicle doors or just one specific door? Can you hear the central locking motor attempting to work? Are there any other electrical issues like window controls or mirror adjustments affected? Have you noticed any warning lights on the dashboard? This information would help determine if you are facing the same door switch connectivity issue or if there might be a different underlying problem.

My S8 has 196268 KM on the odometer. Appreciate the feedback. The issue affects all vehicle doors simultaneously. The central locking system makes no sound when attempting to operate the automatic locks. Both window controls and mirror functions work normally, and there are no warning lights on the dash. The wiring harness suggestion makes sense as a potential cause. I also noticed that none of the interior door lights activate when opening any door, which could point to a broader door sensor communication problem. Will have the workshop check these specific areas during diagnostics.

The lack of any central locking sound combined with non-functioning door lights across all doors suggests this could be more than just a single wiring harness issue like I experienced with my S6. Since the car alarm and overall door security system relies heavily on proper door contact signals, a failure in the central control module might be the root cause. After my initial wiring harness repair, I actually encountered a similar complete system failure months later. The workshop discovered the Body Control Module (BCM) was not properly processing door sensor inputs. The car sensor network essentially stopped recognizing door status changes entirely. The fix required: Full diagnostic scan of the BCM, Reprogramming of the door control systems, Replacement of one faulty door sensor, Total repair cost was around 450 Euro Given your symptoms match the secondary issue I faced, particularly the complete silence from the central locking and no door lights, I would suggest having the BCM checked first. The high mileage could be a factor in control module degradation. The good news is your working windows and mirrors indicate the door wiring harnesses themselves may be intact, unlike my first issue. Would you mind checking if your key fob battery is fresh? While it likely wont solve the core issue, eliminating weak remote signals helps narrow down the diagnosis.

Based on all the troubleshooting suggestions and similar experiences shared, I better understand what might be happening with my S8. The systematic failure across all vehicle doors and complete lack of door sensor response does point toward a BCM issue rather than individual wiring problems. The fact that other door-related electrical systems like windows and mirrors work properly is somewhat reassuring. Will definitely have the workshop focus on the Body Control Module and door sensor network during diagnosis. Already checked the key fob battery, its new and working fine. Think its time to schedule the repair since this affects basic security functions. The 450 Euro repair cost mentioned seems reasonable if it resolves all door sensor communication issues. At least now I can explain the specific symptoms to the technician and point them toward checking the BCM and door contact signals first. This should help reduce diagnostic time and costs. Will update once I know the actual cause.