BMW 7 Series Light System Malfunction, Solutions Needed

Hey there! I have some experience working on BMWs. Had a similar issue with my 2006 BMW 5 series (so I feel your pain!). The symptoms you're describing sound exactly like what I dealt with. In my case, it turned out to be a faulty connection in the wiring harness going to the light switch module. My mechanic found that some pins in the connector were corroded, causing weird behavior in the lighting system. It was a relatively straightforward fix, they cleaned the connections and replaced some damaged wiring near the plug. Cost me around 95 Euro, and it's been working perfectly since then. Before jumping to conclusions though, could you share: Does this happen all the time or intermittently? Have you noticed any other electrical issues? Are you getting any specific error codes? This could help narrow down if you're dealing with the same problem I had or if it's something else.

Thanks for the detailed response! I have the exact same symptoms happening consistently every time I start the car. No other electrical issues so far, and I'm getting a "lighting system malfunction" message on the dash. Just had my service at 163309 KM, and everything else seems fine mechanically. Will definitely check the wiring harness connections based on your experience. Did your mechanic need any special tools to access and fix the wiring?

Hey again! Thanks for the follow-up. Since we're dealing with such similar issues, I can definitely give you more specifics about my repair experience. My mechanic actually didn't need any super specialized tools, just basic electrical diagnostic equipment and some standard BMW connector tools. The trickiest part was accessing the wiring harness since it's tucked away behind some panels. They used a multimeter to test the connections and some electrical contact cleaner to deal with the corrosion. Since you're getting the same consistent behavior I had, and especially with that specific "lighting system malfunction" message, I'm even more convinced it's the same wiring issue I experienced. The mileage on your car (mine was around 155000 KM when this happened) is right in the range where these kinds of electrical gremlins start showing up. One thing I forgot to mention in my first response, before going to the mechanic, I tried disconnecting the battery for about 15 minutes to reset the system. It didn't fix the problem, but it might be worth trying just to rule out any computer glitches. Just remember you'll need to reset your radio code and clock afterward. Keep us posted on what you find! I'm curious to see if it turns out to be the same issue.

Thanks so much for all the extra details! It's really helpful knowing about the diagnostic process and tools needed. I'll definitely try the battery disconnect trick first, nothing to lose there except maybe a few radio presets! Good to know about the timing of these issues too, makes me feel better that it's probably just normal wear and tear at this mileage. I've already called my mechanic and scheduled an appointment for next week. I made sure to mention the wiring harness issue you experienced, and they said they'd check that first since the symptoms match up so perfectly. They quoted me around the same price range you mentioned if it turns out to be the same problem. Thanks again for taking the time to share your experience, it's really put my mind at ease knowing it's likely not something super major or complicated. I'll update this thread once I get it fixed so others can benefit from our discussion too. Really appreciate the help!