Audi S5 Key Fob Malfunction Due to Antenna Issue

As someone with some hands-on experience working on German cars, I encountered a very similar issue with my 2015 Audi S4. The symptoms were nearly identical, remote unlock stopped working and I had to resort to using the physical key. After diagnosing the problem, it turned out the fm antenna connection in the front section had worked itself loose over time, causing signal interference with the key fob system. The antenna replacement wasn't necessary, it was just a matter of fixing a faulty cable connection. The repair took about an hour and cost 95 Euro including diagnostic time. Since then, the system has worked flawlessly. The key fob range actually improved compared to before the issue started. Before suggesting specific fixes, could you share: Have you noticed any other electrical issues? Does the key fob work better when standing closer to the car? Are you getting any specific error codes? Did this start suddenly or gradually get worse? This could help narrow down whether your automotive antenna issue is similar to what I experienced or if it might be something else affecting the radio signal reception.

Last service done at 18900 KM, just two months ago. Thanks for sharing your experience. The issue started gradually over the past three weeks. Getting error code P0706. The car antenna signal seems stronger when I stand right next to the drivers door versus a few meters away. No other electrical problems noticed so far. I checked the battery in the key fob and its new. I will get the antenna mount area inspected based on your feedback, since the symptoms match exactly what you described. The reduced key fob range definitely points to a signal interference problem that needs checking.

Thanks for those additional details. Your symptoms are matching my experience even more closely now, especially the gradual onset and stronger signal near the driver's door. The P0706 code combined with the antenna signal behavior really suggests this is a vehicle antenna connectivity issue rather than a key fob problem. When my car antenna system started failing, I also noticed the signal was much stronger near the driver side. My repair actually revealed that moisture had created corrosion at the antenna connection point, degrading the signal over time. The car radio was also occasionally cutting out, though I hadnt connected the two issues initially. The repair center found that replacing the corroded antenna wire connections solved both the key fob and radio signal problems. Total cost for my antenna repair was 120 Euro, and the work took about 90 minutes. Given your car is slightly newer than mine but showing identical symptoms, Id recommend: Getting the antenna connections checked first before replacing parts, Having them test the signal strength at different points around the car, Making sure they check for moisture damage near the antenna mount The good news is this type of antenna replacement or repair usually resolves the issue completely without any recurring problems.

Thanks for the thorough explanation about your repair experience. Your situation sounds identical to what I'm dealing with. Getting the antenna mount area checked first makes perfect sense, especially since the signal gets stronger near the drivers door just like in your case. The gradual failure pattern matches too. I will have the shop inspect those antenna wire connections for corrosion and moisture damage when I take it in next week. The quoted repair cost of 120 Euro seems reasonable if it fully resolves both the key fob range and radio signal issues. Really helpful to know they should test signal strength at different points around the car, I will make sure they do that during diagnostics. Good to hear this type of automotive antenna repair tends to be a permanent fix. I was worried I might need to replace the entire key fob system, which would have been much more expensive. Will update once I get it checked out.