BMW 4 Series Warning Light Chaos, Memory Lock Issue?

Hey there! I have some experience working on cars and had a super similar issue with my 2014 BMW 3 series diesel. Those pesky warning lights are definitely frustrating! Had multiple error codes showing up just like yours, and my 5 series friend from the dealership recommended I get it checked ASAP. Turned out it was an undervoltage problem that was messing with the electronics. Got it fixed at my regular workshop, cost me around 240 Euro but solved the issue completely. Can you share which specific warning lights you're seeing and maybe the error codes? That would help me tell if it's the same problem I had. Also, what's your current mileage? This could make a difference in diagnosing the issue.

Thanks for sharing your experience! My issue seems pretty similar. Currently at 156776 KM and just had a service last month. The main warning lights I'm getting are for the engine management system and emissions control. Even after clearing the codes with my basic scanner, they keep coming back within a few hours of driving. The undervoltage issue you mentioned sounds like it could be related, did you notice any other symptoms besides the warning lights? Mine occasionally shows a "reduced power" message too, but it comes and goes out of nowhere. Wondering if I should try checking the battery connections first before heading to the workshop.

Hey again! Thanks for those extra details, and wow, that sounds exactly like what I dealt with! My BMW was around 160,000 KM when I had these issues, so pretty close to yours. The "reduced power" message is super familiar, I had that same intermittent problem! Initially, I also thought about checking the battery connections (actually spent a whole weekend messing with them), but that wasn't the real culprit in my case. While the undervoltage was part of the problem, it turned out the voltage regulator in my alternator was failing, which caused all those unusual warning lights and power issues. Since you mentioned yours happened after a recent service, I'd actually recommend getting it checked professionally rather than trying the DIY route like I did (learned that lesson the hard way!). My mechanic explained that these systems are pretty sensitive, and when one component starts acting up, it can trigger a cascade of error messages. Quick tip though, when you take it in, make sure to mention the timing of when these issues started (especially in relation to your recent service). In my case, this detail helped pinpoint the problem faster. The codes kept coming back for me too until we fixed the actual underlying issue with the alternator. Would love to hear what your mechanic finds, might help other BMW owners dealing with similar headaches!

Thanks so much for the detailed explanation! You've actually saved me from wasting time on the battery connections. It makes total sense about the voltage regulator in the alternator, especially since the problems seem so similar to what you experienced. I've just called my mechanic and booked it in for tomorrow morning. Mentioned everything about the timing and the symptoms, and he seemed to know exactly what I was talking about. Even said they've seen a few similar cases lately with BMWs around our mileage. Really appreciate you taking the time to share your experience. It's given me a much better idea of what I might be dealing with, and I'm feeling way more confident about getting it sorted now. I'll definitely update once I know what the actual problem is, might help someone else down the line dealing with the same issue!