BMW X6 Electrical Nightmare, FlexRay Bus Issues?

Hey there! I have some experience with BMWs, having owned a 2014 BMW X5 and later an X3. I actually faced a similar electrical nightmare last year. Multiple systems went crazy, and I had the same symptoms, power issues, error messages all over, and a dead audio system. Turned out it was a faulty connection in the main wiring harness that was causing all these problems. Took it to my regular workshop, and they did a full diagnostic scan. The mechanic found that one of the main cable connectors was corroded and not making proper contact. They had to clean the connections and replace a damaged plug. Cost me about 95 Euro for the whole fix, including labor. After that, everything went back to normal. Before I can give more specific advice, could you share: Are there any specific error codes showing up? Did these issues start suddenly or gradually? Have you had any recent work done on the car? Does it happen more when the car is moving or stationary?

Thanks for sharing your experience! My X6 is still relatively low mileage at 17449 KM and just had its latest service, so this issue caught me completely off guard. Your electrical problems sound exactly like what I'm experiencing right now. I'll definitely have my mechanic check the wiring harness and connectors. To answer your questions, the issues started quite suddenly during a regular drive. No recent work was done on the car, and the problems persist whether the car is moving or stationary. I'm getting multiple error codes, but they keep changing every time I restart the car. The most consistent one is related to the communication system failure. Really appreciate the detailed explanation about the corrosion issue, that gives me hope it might be something similarly straightforward and not too expensive to fix!

Hey again! Thanks for those extra details about your X6. You know, after I mentioned my wiring harness experience, I actually remembered something else that might be relevant to your case. Since your car is showing those changing error codes and communication system failures, it reminds me of when my X5 had similar symptoms a few months after the wiring harness incident. Turned out the Gateway Control Module was acting up, it's basically the brain that manages all the communication between different systems. The shifting error codes are a classic sign of this. The low mileage on your X6 actually makes me lean more toward this being an electronic control unit issue rather than physical wire damage like I had before. These modules can sometimes fail regardless of mileage, mine did at around 20000 KM. Quick question, have you noticed if the battery voltage is stable? My gateway module problems were initially misdiagnosed as a battery issue because the symptoms were so similar. Might be worth checking that first before diving deeper into more complex repairs. The good news is that if it is the gateway module, it's usually a straightforward fix, just needs reprogramming or replacement. Not as scary as it sounds!

Thanks so much for the additional insights! Actually, now that you mention the Gateway Control Module, it makes a lot more sense. I haven't checked the battery voltage yet, but I'll definitely get that tested first. It's really helpful to know that these modules can fail even with low mileage, I was worried I'd done something wrong! I feel much more confident heading to the mechanic now with these specifics to discuss. Will ask them to check both the battery and the Gateway Control Module. It's such a relief to know it might be something relatively straightforward to fix, rather than having to replace the entire electrical system like I was worried about! I'll probably get it checked tomorrow morning. Really appreciate all your help and taking the time to explain everything in detail. You've definitely saved me some sleepless nights worrying about this! Will update once I know what the actual issue was.