Audi S6 Headlight Control System Malfunction Fix

I had a very similar issue with my 2008 Audi S4. As someone with some experience working on cars, I first thought it was just a basic beam adjustment problem, but it turned out to be more complex. The symptoms matched exactly, inconsistent light intensity and adaptive headlights behaving erratically. After multiple visits to a specialized workshop, they diagnosed a faulty servomotor in the headlight assembly that controls the range control system. The electrical connectors were all intact, but the servomotor itself had failed. The repair involved: Complete diagnostic scan, Removal of headlight assembly, Replacement of servomotor unit, Recalibration of headlight system Total cost was 1040 Euro including parts and labor. Since the fix, the headlight system has worked flawlessly. Could you provide: Current mileage, Whether both headlights are affected, If the issue started suddenly or gradually, Any recent repairs or battery replacements This information would help determine if your case matches mine or might be something different in the adaptive headlight system. Also worth checking if your vehicle has had any water damage, as this can affect the range control sensors and electrical components.

Last service was done at 36165 KM and the issues started shortly after. The auto-leveling warning persists even after the battery tested fine. Trying to avoid expensive part replacements, so knowing the exact component to check helps. The adaptive headlights worked normally before but now the control module seems confused. Would getting the sensors calibrated first make sense before replacing the servomotor?

Thanks for providing those details. The timing after your service is interesting, I had a similar experience with my S4 where issues emerged post-maintenance. Based on my experience, jumping straight to sensor calibration might not resolve the root cause. When my adaptive headlights started malfunctioning, the workshop first attempted a calibration-only fix, but the lighting system problems returned within weeks. In your case, since the issues appeared after service, have the electrical connectors checked first, sometimes they can be accidentally disturbed during routine maintenance. The range control sensors are sensitive to even slight misalignments. My repair progression was: 1. Connector inspection and cleaning (30 Euro) 2. System calibration attempt (120 Euro) 3. Finally, servomotor replacement (890 Euro) The warning light and inconsistent light intensity continued until the servomotor was replaced. The total repair ended up more expensive due to trying partial fixes first. With similar mileage and symptoms to what I experienced, I recommend having the servomotor checked specifically. The control module confusion you mention matches exactly what happened with my S4 before the servomotor failed completely. Have you noticed if the headlight behavior changes more during cold starts or after the car has been running for a while?

The auto-leveling system is definitely acting up worse during cold starts, which matches what you described. I appreciate the detailed breakdown of your repair progression, helps avoid the trial and error approach. Called my mechanic and scheduled diagnostic work focusing on the servomotor first. The adaptive headlights seem most erratic when going over bumps, so checking those connectors makes sense too. Given the similar mileage and symptoms, I will likely end up needing the servomotor replacement but at least now I know what to expect cost-wise. I just hope the headlight malfunction can be resolved with just the servomotor and not the entire control module. Will update once I get it checked out and see if the light intensity issues get fully resolved. Thanks for sharing your experience with nearly identical symptoms.