Land Rover Discovery Heated Windows System Failure Fix Needed

Hey there! I have some experience working on cars, and I actually dealt with something very similar with my 2010 Land Rover Range Rover (gas engine). What you're describing sounds exactly like what happened to me, turns out my battery was on its last legs and couldn't provide enough power for the heating elements. The computer showed similar fault codes and nothing worked when I tried the switches. Took it to my regular workshop last winter, and they diagnosed it pretty quickly. The battery replacement plus diagnostic work came to about 290 Euro, but it fixed everything, all heating elements started working perfectly again. Before you head to the shop though, what's your battery's age and have you noticed any other electrical issues lately (slow starts, dim lights)? Also, can you share if there were any specific error codes showing up? This would help narrow things down. BTW, if you want to try something simple first, check the fuses, there should be one specifically for the heated windows system.

Thanks for your detailed reply! My Discovery has 64395 KM and had its last service about 3 months ago. I haven't noticed any other electrical issues actually, starts fine, lights are normal, and everything else seems to work perfectly. I checked all the fuses yesterday (including the one for the heated windows), and they're all good. The computer just shows "System Fault" without any specific error code, which is kind of frustrating. I hadn't thought about the battery being the culprit since everything else works fine, but maybe it's worth checking. The battery is about 2 years old though, so I'd be surprised if that's the issue. Anyone else had similar experiences with just the heated windows failing while everything else works normally?

Hey again! Looking at what you're describing now, I'm actually starting to think it might not be the battery after all, especially since yours is only 2 years old and you're not having any other electrical issues. My Range Rover definitely showed other symptoms when the battery was failing. Since we have basically the same heating system (Land Rover family, right?), I can tell you that in my experience, these symptoms could point to a broken heating element or a faulty relay. After my battery episode, I actually had another similar issue last summer, turned out to be a corroded connection at the heating element terminals. Was a much cheaper fix than the battery replacement! Have you tried listening for the relay click when you turn on the heated windows? On my Rover, I can hear it near the fuse box. If there's no click, that might be your problem right there. Also, you might want to check the connections at the back window, sometimes moisture gets in there and causes corrosion. That's what happened to mine. Give these a check and let me know what you find. If you can't hear the relay or spot any obvious connection issues, might be worth getting it properly diagnosed. These Land Rovers can be tricky sometimes, but they're great cars when everything's working right!

Thanks for these suggestions! After checking what you mentioned, I think I'm getting closer to finding the problem. I tried listening for the relay click like you suggested, and there's definitely no sound when I turn the system on. That seems like a pretty good clue! I also had a look at the back window connections, and while I couldn't spot any obvious corrosion, I noticed one of the terminals looks a bit loose. I tried wiggling it gently, and it definitely has more play than it probably should. I'll probably take it to the workshop next week to get it properly checked out. Between the silent relay and that loose connection, at least I can give them some specific things to look at. Really hoping it's just the relay or a connection issue rather than something more serious! Thanks again for sharing your experience, it's super helpful to know what to look for, especially with these sometimes quirky Land Rovers. I'll update once I find out what the actual problem was!