BMW XM Light Control System Failure, Common Switch Issue?

Hey there! I've got some experience with car maintenance, and funny enough, I had a similar issue with my 2021 BMW X7 last year. The lighting system went completely crazy, same symptoms as yours. After scratching my head for a while, I took it to my trusted workshop and turns out it was a faulty connection in the wiring harness near the light switch module. They found some corroded pins in the connector. The fix wasn't too complex, they replaced the connector and rewired that section. Cost me 95 Euro and it's been working perfectly since then. Before I can help more specifically, could you share: Did this start suddenly or gradually? Are you getting any specific error messages on the dashboard? Have you noticed any water damage or moisture around the light switch area? My with a BMW X6 had similar issues but his turned out to be different, so these details would help narrow things down.

Thanks for sharing your experience! Mine started quite suddenly actually, just while driving home one evening. The error message reads "External lighting system malfunction" and the dashboard shows the typical headlight warning symbol. Got it serviced just last month at 148685 KM, and everything was fine then. Haven't spotted any moisture around the switch, but I'm wondering if it could still be a wiring issue like in your case. It's extra annoying because the car is still pretty new, and you wouldn't expect these problems on a 2023 model. Think I might need to bite the bullet and take it to the workshop, just wanted to get some insights first to avoid getting ripped off. Your repair cost sounds reasonable, hoping mine will be in the same ballpark!

Hey again! After seeing your additional details, I'm even more convinced it's similar to what I experienced. The sudden onset and that specific error message, "External lighting system malfunction", is exactly what I saw on my X7 too. You're right, it's pretty unusual for a 2023 model to have these issues. Mine was actually a bit older when it happened, which made more sense. Since yours is so new, I'd definitely push this under warranty if I were you. My repair was relatively cheap because it was just the connector and some rewiring, but you shouldn't have to pay anything on such a new vehicle. Just to share a bit more from my experience, before I got it fixed, I tried checking the fuses and even disconnecting the battery for a reset (classic IT-style "turn it off and on again" approach!). Neither worked, which is what led me to suspect a deeper wiring issue. Given the similarities to my case and considering it's a 2023 model, I'd suggest going straight to a BMW dealer rather than an independent workshop like I did. They should be able to properly diagnose it and fix it under warranty. Plus, they'll have access to all the latest technical bulletins, there might even be a known issue with the 2023 models that they're aware of. Let us know what they find when you get it checked out!

Thanks so much for all the detailed advice! You've definitely helped calm my nerves about this whole situation. You're absolutely right about the warranty, I just called the dealer and they're taking it in tomorrow morning. The service advisor actually mentioned they've seen a few similar cases lately, so hopefully they'll know exactly what to look for. Really glad I didn't try any DIY fixes that might've voided the warranty! Still can't believe your X7 had almost the identical issue, that error message match is pretty wild. It's actually reassuring to know it was just a wiring problem in your case and not something more serious. I'll definitely update the thread once I get it back from the dealer. Thanks again for taking the time to share your experience, it's made this whole headache a lot more manageable! Fingers crossed it's as straightforward as your repair was.