Failing Audi Key Fob? Simple Battery Fix May Help

I had a similar issue with my 2015 Audi A4 last winter, and having dealt with key fob problems before, I can likely help. The symptoms you describe, unreliable keyless entry and low voltage warnings, match exactly what I experienced. The dashboard warning about low key battery is usually quite accurate on these models. In my case, the key fob battery replacement solved all these issues completely. I visited a workshop since I wanted to ensure there were no underlying problems with the car's receiver system. They confirmed it was just a dead key fob battery. The replacement cost was 37 Euro total, including labor and a new CR2032 battery. If you want to be certain about the diagnosis, could you provide: Does the physical key blade still work normally? When did you last replace the key fob battery? Are you experiencing any other electrical issues? Do you have a spare key fob to test? Most key fob batteries last 2-3 years, so if yours is original, its definitely time for replacement. The good news is this is typically a straightforward fix that doesnt indicate any serious problems with the cars electrical system.

Thanks for the previous responses. Just had my latest service at 71671 KM and the mechanic confirmed it was indeed a low voltage issue with the key fob battery. Changed it for 5 Euro and the keyless access started working perfectly again. The auto key system is quite sensitive to battery power levels, even when the battery still has some life, the keyless detection can start failing. For anyone else facing this, worth checking the battery first before assuming more complex issues. Saved myself an expensive diagnostic fee by starting with this simple fix.

Good to hear you got it sorted out with just a battery replacement! These electronic key systems really are quite sensitive to voltage fluctuations. My A4 had the exact same behavior, the keyless access started acting up well before the key fob battery was completely dead. Just a tip for future reference, I now keep a spare CR2032 battery at home since these key fob failures tend to happen at the most inconvenient times. The battery usually gives some warning signs like reduced range before failing completely, but its still worth being prepared. The 5 Euro fix you found is much better than the workshop charges I initially paid. Since then, Ive learned to do the battery replacement myself. These electronic keys might seem complex, but the battery swap is actually quite straightforward once you know how to open the key housing properly.

Thanks to everyone who replied. After my initial post and getting advice here, I wanted to update that the key fob battery replacement completely fixed my A5s keyless access issues. The 5 Euro fix was exactly what was needed, no complex problems at all. The service center confirmed the low battery warning was accurate. For others searching with similar symptoms, unreliable detection when approaching the car and inconsistent locking/unlocking, definitely check your key fob battery first. The dead key symptoms started gradually, but replacing the battery immediately restored full functionality. Much better to try this simple fix before assuming worse problems or paying for expensive diagnostics. Really appreciate all the helpful responses. Having a working keyless system again makes such a difference in daily use. Will definitely keep a spare CR2032 battery on hand for next time the key starts acting up.