VW Key Fob Dead Despite New Battery, DIY vs Mechanic Fix

Had the same problem with my 2015 VW Golf TSI. The key fob completely died despite replacing the battery several times. The warning about low battery in the key kept appearing on the dashboard. A simple battery replacement did not solve it because the key fob circuit board had corroded contact points. The mechanic found this after opening the key shell. What seemed like a basic key battery issue turned into a more complex repair requiring reprogramming of a new key fob to sync with the car security system. The key needed complete replacement since the internal damage was beyond repair. This is a known issue with some VW key fobs where moisture gets trapped inside over time. The auto key programming required special diagnostic equipment that only authorized shops typically have. Attempting DIY fixes beyond battery replacement risks damaging the immobilizer system. The car security system is directly tied to the key fob functionality, so professional diagnosis is recommended. This was not a quick fix but also not a major mechanical issue, just an electronic security component that needed proper replacement and programming. Since it matches your symptoms exactly, suggest having a professional check the key fob internals rather than continuing with battery replacements that wont solve the underlying problem.

Thanks for the detailed response. Really helpful to know about the corroded contacts, makes sense why just swapping the electronic key battery didnt fix it for me either. Quick follow up, curious what the total repair cost was for your case? Always good to have a ballpark figure before heading to the shop. Also wondering if youve had any issues since getting the new key fob programmed? My VW is still showing that low voltage warning for the key even after multiple battery changes, so looks like Ill need to bite the bullet and get it properly checked out.

Getting the key fob properly fixed was worth every cent. The mechanic found corroded contacts just like in your case. Total repair came to 37€ for a complete fix of the low battery warning and key functionality. The auto key works flawlessly now, no more dead key issues or low voltage warnings on the dashboard. The programming was done right the first time and hasnt needed any adjustments since. The car recognizes the key fob perfectly for both locking and unlocking. Those persistent low battery warnings you are seeing, even after changing batteries, definitely point to the same internal corrosion problem. Getting it checked by a professional will likely save you from repeatedly buying batteries that cant solve the actual issue. Since having it properly repaired, the keyless entry system has been completely reliable. No more frustration with an unresponsive key fob or warning messages. The fix was straightforward once in qualified hands with the right diagnostic equipment.

The shop visit went better than expected. Called my usual mechanic who actually specializes in VW electronics and booked me in right away. After checking the key fob, they found exactly what was described, corroded contact points inside that were preventing proper connection even with a new battery. Total cost came to 45€ for diagnostics, new key programming and fixing the internal contacts. The mechanic showed me the corrosion damage and explained how moisture had gotten trapped inside over time. They also cleaned the electronic key components before reassembly. Really glad I didnt keep throwing money at battery replacements. The auto key works perfectly now, no more warnings on the dashboard and the keyless entry is responsive again. Would definitely recommend getting it properly diagnosed rather than trying more DIY fixes. The whole repair took about an hour and saved me from potentially bigger issues with the car security system. Sometimes paying for professional expertise is the smart move, especially with modern vehicle electronics.