BMW 6 Series Electrical Nightmare, Multiple Systems Down

Hey there! I have some experience working on BMWs. Had a similar nightmare with my 2012 BMW 5 series diesel (also own a 3 series). Those electrical gremlins can be super frustrating! Had exactly the same symptoms, everything going haywire at once. Turned out to be a faulty wiring connector in the FlexRay system. Got it sorted at my local workshop for around 95 Euro, they found a damaged cable connection that was causing all these unusual failures. Quick question, are you getting any specific error codes? Would help to know which systems are acting up. Also, does it happen more when the engine's warm or cold? This info could help pinpoint if we're dealing with the same issue. Let me know these details and I might be able to share more specific tips from my experience.

Thanks for the detailed response! My car has only done 8982 KM since the latest service, and I'm getting error code 2AFB89 consistently. The issues seem to occur more frequently when the engine is warm, usually after about 20 minutes of driving. The weird thing is that all systems temporarily restore when I turn the car off and on, but then fail again after a few minutes. I'll definitely check the wiring connectors you mentioned. Do you remember which specific area of the wiring harness your mechanic found the fault in? Really hoping it's a similar simple fix and not something more serious with the main control unit.

Hey again! The issue you're describing sounds exactly like what I faced. That same error code (2AFB89) kept popping up in my 5 series too, and the whole on-off-on thing working temporarily is super familiar, drove me nuts for weeks! In my case, the faulty connector was located behind the glove compartment, where several wiring harnesses come together. My mechanic initially thought it might be the main control unit (which would've been way more expensive), but thankfully it was just this sneaky little connector that had worked itself loose and was causing intermittent contact. The fact that it's happening when the engine's warm makes total sense, that's when everything expands a bit and these connection issues tend to show up. Mine did exactly the same thing, and it was definitely worse in warmer conditions. Quick tip from my experience, if you're heading to the workshop, try to recreate the issue right before you go in. Makes it much easier for them to diagnose. When I first took mine in, everything was working perfectly (typical, right?), and it took them longer to find the problem. Would be interested to hear what they find in your case. Pretty confident it's going to be something similar to what I had, especially with those identical symptoms and error code.

Thanks so much for this information, it's incredibly helpful! You've given me hope that this won't be as expensive as I feared. I'll definitely try to recreate the issue before taking it to the workshop, that's a really good tip. I've actually already booked it in for tomorrow morning and made sure to note down all the symptoms and that error code. The location you mentioned behind the glove compartment makes a lot of sense, as I've noticed the issues seem worse when I'm using the climate control. I'll make sure to mention this specific area to the mechanic, might save them some diagnostic time. Really appreciate you sharing your experience in such detail. I'll update the thread once I get it sorted, in case anyone else runs into similar problems in the future. Thanks again for taking the time to help out!