VW Lupo Key Fob Failure: Common Remote Lock Issue

I had almost the exact same issue with my 2000 VW Polo diesel last winter. As someone with basic car maintenance experience, I first thought it was just a low battery problem in the key fob. After replacing the key battery myself, the remote functions still did not work. Like in your case, the mechanical key function remained fine. Turned out there was more to it than just a simple battery replacement. Took it to a workshop where they diagnosed the actual problem, the receiver module for the central locking system needed recalibration. The total repair cost was 37€ including programming and a system check. Before suggesting specific solutions, could you share: Have you noticed any other electrical issues? Does the problem occur with all key fobs if you have spares? Are there any other warning lights on the dashboard? Did the issue start suddenly or gradually? This information would help determine if your issue matches what I experienced or if there might be a different underlying problem with the central locking system. The key battery replacement alone rarely fixes these types of issues in older VW models, as there is often a connection problem between the key and the car receiver that needs professional diagnostic equipment to resolve.

Thanks for your detailed response. Last service was at 113906km in November, which is when they also ran a full diagnostic scan. To answer your questions: No other electrical issues noticed, Only have one auto key, no spare to test with, No warning lights on dash besides the key warning, Problem started gradually over 2 weeks The central locking started working intermittently before failing completely. Given your experience with the receiver module, I will get it checked at a workshop. Good to know a dead key fob battery was not the root cause in your case, even though that seemed like the obvious fix. Would you remember if they had to order any specific parts for the repair, or was it purely a recalibration job? Just trying to plan ahead for potential costs and repair time.

Thanks for providing those details. In my case with the VW Polo, it was indeed just a recalibration issue with no parts needed. However, after seeing your symptoms develop over 2 weeks, this sounds more like a failing receiver module rather than just needing recalibration. When my car had this problem, the failure was sudden rather than gradual. A gradual decline often points to hardware deterioration in the central locking system. The workshop should be able to determine if the receiver needs replacement rather than just reprogramming. Getting a spare key fob programmed at the same time might be worth considering. Having a single auto key is risky, and most workshops can program a new one while they are already connected to the system. A new key fob with programming typically costs between 80-120€. For the receiver module repair, labor time is usually around 1-2 hours. The part itself, if needed, ranges from 150-200€. Worth mentioning that some workshops can repair the existing module which costs significantly less than replacement. Best to schedule the diagnostic first, they can confirm whether its truly a hardware issue or if recalibration alone might work like in my case.

Thanks for the extra info regarding repair times and costs. Your situation with the sudden failure versus my gradual decline does suggest different root causes. I will schedule a diagnostic check next week. The repair pricing you mentioned helps set realistic expectations, good to know it might be around 200-300€ total if the receiver module needs replacing. The suggestion about getting a spare electronic key programmed makes sense. Having just one car key has been making me nervous anyway. Will definitely ask about that while they are working on the central locking system. Do you recall if the recalibration fix lasted, or did you have any recurring issues with the key fob system afterward? Just want to make sure that if I end up needing a full receiver replacement, it is worth the extra cost versus just trying recalibration first.