Audi S6 Key Fob Dies: Common Fixes and Costs

Had the exact same issue on my 2014 Audi S4 last month. With moderate experience working on cars, I first thought it might be something complex, but it turned out to be a straightforward fix. When the key fob started acting up with the same symptoms, no keyless entry, inconsistent locking, I got that battery warning message too. Took it to a workshop to be safe, since dead key fobs can sometimes need reprogramming even after battery replacement. The diagnosis confirmed it was just a drained key battery. Total cost was 37 Euro for the battery replacement and checking the programming. The shop tested the key fob thoroughly after to ensure all functions were working properly again. Quick tip: There is still a physical key hidden inside most key fobs that can be used if the battery dies completely. Worth knowing for emergencies. What warning messages are you seeing on your dashboard exactly? Also, how long have you had these symptoms? This info would help confirm if your situation matches what I experienced.

Last service done at 111187 KM in December. Thanks for the replies so far. Started seeing car key battery warning messages about a week ago. At first, the key fob worked intermittently, then stopped completely. Now seeing Key System Error on the dash when trying to start the car. Tried using the mechanical key inside the fob to at least get in the car manually, but even after getting in, the push-start sometimes fails to recognize the key fob presence. Getting really frustrating as its my daily driver. Will try the fob battery replacement first since it seems the most logical and cost-effective solution based on your experience. Good to know the programming check is part of a proper auto key service. Hope its just the battery and not a more serious electronic issue. Just called around and found a battery replacement service for 45 Euro. Will update once I get it done.

Your situation sounds nearly identical to what I dealt with on my S4. When my electronic key started failing, I also noticed it was gradual, first those battery warnings, then intermittent function, and finally complete failure with similar error messages. The key battery replacement fixed all those issues completely. The push-button start problems you mentioned are classic symptoms of a weak key fob battery, when the battery gets too low, the car cant reliably detect the key presence. 45 Euro is reasonable for a professional key battery service. Make sure they test all functions after replacement: keyless entry, trunk release, remote start if equipped, and most importantly, the push-button start detection. If the problems persist after getting a fresh battery, then we might need to look at other potential causes. But based on the progression of symptoms you described, Im confident youre dealing with the same straightforward battery issue I had. Would definitely appreciate an update after you get the service done. Good move going with a proper service rather than attempting a DIY battery swap, since they can verify everything is working correctly.

Thanks for sharing those details about your experience. The progression of issues you described matches my situation perfectly. These symptoms really started getting bad this week, and that Key System Error on the dash is exactly what Im seeing now. The 45 Euro battery replacement service sounds like a fair price, especially since they will check the programming too. Much better than risking damage trying to change the fob battery myself. Really hoping this fixes the keyless entry and push-start issues like it did in your case. Planning to get the key battery replacement done tomorrow morning. Will definitely post an update here about the results. The fact that your S4 had the same symptoms and was fixed with just a battery gives me hope its not something more serious with the electronics. Just glad I can still use the emergency key to get in the car for now. Really appreciate everyone sharing their experiences, helps narrow down the most likely solution before spending money on unnecessary repairs.