BMW Z3 Haunted Lights: Switch Gone Rogue?

Hey there! I've got some experience with electrical issues. Had a similar problem with my 2004 BMW Z4 last year, and my cousin owns a Z3. The symptoms you're describing sound exactly like what I dealt with. In my case, it turned out to be a faulty cable connection at the light switch module. The connections had corroded over time, causing all sorts of weird lighting behavior. Took it to my regular workshop, and they diagnosed it pretty quickly. They had to replace some wiring and clean up the connection points. Total bill was around 95 Euro, and it fixed the issue completely, no more crazy lights! Could you share more details about your Z3? Like, have you noticed any other electrical issues, or did this start happening suddenly? Also, which specific error code are you getting? This would help narrow down if you're dealing with the same problem I had. Quick tip: If you're having issues with the low beam staying on, don't wait too long to get it checked, it can drain your battery pretty quickly.

Thanks for sharing your experience! I've had my Z3 since last year (128556 KM on the clock), and this issue popped up rather suddenly after my latest service. No other electrical problems before this. The error code seems similar to what you mentioned, I'll double-check it and let you know. That's really helpful about the cable connection. Considering the age of these cars, corrosion makes total sense. I'm a bit relieved it might not be something more serious. My battery has been holding up okay so far, but I'll get it checked out soon at the shop. Did your mechanic have to order any special parts, or was it mostly just repair work on the existing wiring?

Hey again! Thanks for the follow-up. Good to hear from another Z-series owner. Yes, with my Z4, it was mostly repair work on the existing wiring, nothing too fancy needed. The mechanic mainly had to clean up the corroded parts and replace a small section of wiring that was too far gone. They actually had the basic wiring parts in stock, so no special ordering was needed. Since you mentioned yours started after a service, that's actually interesting, could be that something got disturbed during the work. When mine acted up, it was totally unusual. Quick question, have you noticed if the problem gets worse when it's damp or after rain? In my case, moisture definitely made it more noticeable, which was another clue pointing to the corrosion issue. Also, while they were fixing my wiring issue, they gave the whole lighting system a once-over and found a couple of other spots that were starting to show early signs of wear. Might be worth asking your mechanic to do the same, better to catch any potential issues early, especially with these older models. Let me know how it goes when you get it checked out. Always good to compare notes with fellow BMW owners!

I'd reply with: Thanks so much for all this detailed info! That's really interesting about the moisture making it worse, now that you mention it, I have noticed the lights acting up more on damp days. It's like the car's telling me "hey, better get this fixed soon!" I've booked it in at the workshop for next week. I'll definitely ask them to do that full lighting system check you suggested, makes total sense to catch any other potential issues while they're in there. Better to fix everything at once than keep going back. The tip about the corrosion spots being common in these older models is super helpful. I'm actually feeling pretty optimistic now that this won't be some massive repair job. Will update you on what they find, seems like it might be quite similar to what you experienced with your Z4. Really appreciate you taking the time to share all this. It's always so much better heading to the mechanic with some idea of what might be going on!