BMW Turn Signals Gone Haywire, Xenon Lights Turning Purple

Hey there! I had a similar issue with my 2017 BMW 3 Series diesel last summer. The symptoms were nearly identical, weird dashboard alerts and funky lighting behavior. Turned out the main wiring harness had corroded connections near the headlight assembly, and one of the ballasts for the xenon lights was failing. My mechanic found that moisture had gotten into the connector housing, causing intermittent signal problems. The purple tint you're seeing is typically a clear sign that the xenon bulbs are at the end of their life. For me, this wasn't just a minor inconvenience, driving with unreliable signals and improper lighting is pretty unsafe. The fix involved replacing the wiring harness section, both ballasts, and the xenon bulbs. Not a quick job since they had to partially disassemble the front end to access everything properly. I wouldn't recommend putting this repair off, electrical issues tend to get worse and can affect other systems. Just my experience, but worth getting it checked out by a BMW specialist who knows these systems well. Best of luck!

Thanks for sharing your experience, this sounds exactly like what I'm dealing with! The wiring harness diagnosis makes total sense given all the symptoms. Glad you got it sorted out. Would you mind telling me how much you ended up paying for the whole repair? Also curious if you've had any other electrical gremlins pop up since getting it fixed?

Hey again! Great news, I can give you a much better update now! After seeing my mechanic last week about those turn signal problems I mentioned earlier, it turned out to be way simpler (and cheaper!) than my original repair. Just a faulty cable connection that needed fixing, nothing like the major wiring harness issue I initially dealt with. Only cost me 95€ to sort out the turn signals this time. The mechanic found a loose connection in one of the plugs that was causing the intermittent failures. Once they secured that properly, everything's been working perfectly. Such a relief! And to answer your question about other electrical issues, nope, haven't had a single problem since getting it fixed. My BMW's been running like a charm. Sometimes these electrical gremlins turn out to be much simpler than we fear. Definitely worth getting it checked out sooner rather than later though, you don't want to mess around with faulty signals! Let me know how yours turns out!

Thanks for the update! I actually went ahead and got mine checked yesterday. What a relief, it wasn't nearly as bad as I feared! The mechanic found that one of the connectors had worked itself loose over time, and there was a bit of corrosion on the terminals. They cleaned everything up, secured the connections properly, and replaced one xenon bulb that was on its way out. The whole thing came to about 150 bucks, way less than I was expecting after hearing horror stories about BMW repairs. The turn signals are working perfectly now, and those annoying dashboard warnings have disappeared. The lighting is back to normal too, no more purple tint! Really glad I didn't put this off any longer. The mechanic mentioned that catching these issues early probably saved me from more expensive repairs down the line. They also showed me what to look out for in the future, which was super helpful. Thanks again for sharing your experience, it gave me the push I needed to get this sorted out!