SQ5 Key Fob Failure Despite Ultra-Low Mileage

Had the same issue with my 2016 A6 3.0 TDI. The key fob symptoms match exactly what you describe, keyless entry failure and dashboard warnings about the key not being detected. A dead key battery causes these exact problems. When the key fob battery gets too weak, the car cannot detect the key properly at a distance, forcing you to use manual unlock. This is actually a built-in safety feature so you dont get stranded. The fix is straightforward, just a key battery replacement. Most auto key fobs for these models use CR2032 batteries. Not a serious repair at all. The key battery can be changed at home with basic tools, though the dealer can do it too. In my case, I first suspected something more complex with the key antenna system, but the new battery resolved everything immediately. The keyless entry started working again and all error messages cleared. Worth noting that key fob batteries typically last 3-4 years, so with a 2013 model, this timing makes sense. Would definitely try replacing the battery before investigating other issues.

Thanks for sharing that experience. I was facing identical low voltage symptoms with my SQ5 a few months back. Just like you mentioned, the keyless entry stopped working, requiring manual unlocking every time. Very frustrating. A simple battery replacement in the electronic key fixed everything for me too. The error messages disappeared right away and all functions returned to normal. Would you mind sharing what you paid for the fix? Also curious if youve had any similar issues pop up since the battery change? My key battery lasted almost exactly 4 years before showing these dead key symptoms, which seems pretty standard from what others have shared here in the forum.

Thanks for asking about the follow-up. Since getting the new battery installed in my key fob, all issues have completely resolved. The keyless entry system works perfectly again and those annoying low battery warnings are gone. The dealer charged 37 Euro for the complete fix, which included the battery and labor for the electronic key replacement. No similar problems have occurred in the months since, the car recognizes the key fob immediately and all functions work as intended. Four years seems to be the typical lifespan for these key batteries, so I plan to be proactive and replace it again around that mark to avoid any sudden failures. For reference, my old key fob battery had dropped to such a low voltage that the car could barely detect it even at close range. The new battery restored full functionality and range to the keyless system. If anyone else experiences similar symptoms with their key fob, a battery replacement should be the first thing to check.

Thanks everyone for the advice! Wanted to share how it all worked out. Took it to a local shop last week for the key battery replacement. Only cost me 42 Euro total and fixed everything right away. The mechanic showed me the old battery was completely drained when they tested it. Been running perfectly since then, keyless entry works like new and those annoying error messages are gone. The shop explained these car key issues are super common after 3-4 years, just part of regular maintenance. Much better experience than my last repair visit and saved me worrying about bigger problems. Good to know for next time the key starts acting up. Pretty happy with such a simple fix for what seemed like a major issue at first. Thanks again for pointing me in the right direction with this!