BMW 5 Hybrid Electrical Chaos: Multiple System Failures

Hey! I have some experience working on hybrids and had a very similar issue with my 2013 BMW ActiveHybrid 3. Those symptoms sound exactly like what I dealt with, unusual warnings, system failures, and driving mode glitches. The 3 and 5 series share quite a bit of technology. Turned out it was a faulty cable connection to the main control unit that connects to the BUS system. My mechanic found it during diagnostics, and it was causing all sorts of communication issues between different modules. Cost me about 155 to get it sorted, but the car's been running perfectly since the repair. What error codes are you getting specifically? Also, how long has this been happening? Knowing these details would help confirm if you're dealing with the same issue I had. Trust me, don't wait too long to get it checked, these electrical gremlins can sometimes lead to bigger problems if left unattended.

Thanks for sharing your experience! My car's been acting up for about 3 weeks now. Got multiple error codes but mainly P0A9C and U0293. Just had my service done at 104,783 KM so it's pretty frustrating to deal with these issues now. Been keeping a log of when these glitches happen, and it seems more frequent during cold starts. Really hoping it's just a connection issue like yours and not something more serious with the hybrid system. Would be great to hear if anyone else has dealt with these specific error codes before taking it to the shop.

Hey again! Those error codes definitely caught my attention because they're exactly what I saw on my ActiveHybrid too. Just wanted to add to my previous response, I actually had those same codes (P0A9C and U0293) show up when my issue started. And funny enough, mine also acted up more during cold starts! The cable connection problem I mentioned earlier was actually part of a bigger issue, there was some corrosion on the connector pins that was causing intermittent contact. That's why it was worse during cold starts, the temperature changes were affecting the connection quality. My mechanic ended up cleaning the connectors and applying some dielectric grease to prevent future corrosion. After dealing with this for a few weeks like you are now, I learned that these hybrid systems are super sensitive to any communication disruptions. The cold start correlation is actually a pretty good indicator that it's likely an electrical connection issue rather than a major hybrid system problem. Since you just had your service done, maybe check if they disconnected anything during maintenance that might not have been properly reconnected. My issues started right after an oil change, when they had to remove some covers to access everything. Keep that log you're making, it'll be super helpful for the mechanic. Hope this helps ease your mind a bit about the whole situation!

Thanks so much for the detailed follow-up! You've actually made me feel a lot better about the whole situation. The correlation with your experience, especially the cold start issues and identical error codes, is really reassuring. I just checked my service records and they did have to remove quite a few covers during the last maintenance, so your theory about disconnected components makes total sense. I'll definitely mention the connector corrosion possibility when I take it in. The dielectric grease solution sounds like a smart preventive measure too. My log shows the issues getting slightly more frequent, so I've booked an appointment for next week. Really hoping it'll be a straightforward fix like yours was. Thanks again for taking the time to share your experience, it's been super helpful in understanding what might be going on with my car!