BMW i8 Hybrid: Multiple System Failures Puzzle Owners

Hey there! I can relate, had a similar issue with my 2018 BMW i3. I've got some experience working with hybrid cars, though I'm no expert mechanic. When my AC system died completely, I initially thought it was just low refrigerant, but it turned out to be a faulty AC control unit. The symptoms were identical to yours, no climate control, error messages, the works. Took it to my usual workshop where they diagnosed it properly. The repair involved replacing the entire control unit, which set me back about 980 Euro, but it fixed everything. Before I can provide more specific advice, could you share: Are you getting any specific error codes? Did this start suddenly or gradually? Have you noticed any unusual sounds from the AC system? BTW, if you have a local BMW specialist familiar with the i8 (it's quite different from my i3), I'd recommend having them take a look, as hybrid systems can be tricky. Let me know these details, and I might be able to help further!

Thanks for chiming in! Just had my car serviced last month, and now at 170222 KM, this issue popped up out of nowhere. You might be onto something with the control unit theory. The error codes I'm getting are P0532 and P0533, which do point towards an AC system problem. It happened quite suddenly, was working fine one day, completely dead the next. No weird sounds though, just total silence when trying to operate the climate control. I've heard the i8's system is more complex than the i3's, but it's encouraging to hear your issue was fixable. Did your repair come with any warranty? I'm a bit concerned about the potential cost, especially given the i8's specialized components. Really appreciate the input!

Hey again! Yeah, those P0532 and P0533 codes definitely ring a bell, they're related to the AC pressure sensor circuit. In my case with my i3, I initially thought it was just the control unit, but after seeing your codes, I remembered I actually had similar codes before the complete failure. Just to share my full experience: after the initial repair with the control unit (which did come with a 2-year warranty), the problem actually came back about three weeks later. Turned out the pressure sensor was the root cause, and it was messing with the entire AC system. The control unit was fine, it was just getting wrong readings from the faulty sensor. The second repair was much cheaper, around 300 Euro for the sensor replacement. Since then (about 18 months now), everything's been working perfectly. No error codes, climate control's responsive, and the AC blows nice and cold. Given your codes and symptoms, I'd bet you're dealing with a similar pressure sensor issue rather than a complete control unit failure. Might save you some serious cash if you get that checked first. The sensor is usually easier to replace too, my car was in and out of the shop in a couple of hours. Just make sure whoever works on it knows their way around hybrid systems. These cars are pretty sophisticated, and you don't want someone learning on the job with your i8!

Thanks so much for the detailed reply! This is exactly the kind of insight I was hoping for. Those pressure sensor symptoms match up perfectly with what I'm experiencing. It's really helpful to know about your experience with the initial misdiagnosis too, might save me from going through the same expensive trial and error. I feel much more confident now about approaching the repair. Going to have the pressure sensor checked first before letting them touch the control unit. 300 Euro sounds way better than 980! Though I'm guessing the i8 parts might cost a bit more, at least I know what to expect. Really appreciate you taking the time to share your experience, especially the follow-up details about the warranty and the actual fix. Think I'll book it in for service tomorrow and specifically mention the pressure sensor issue. Thanks again for helping me dodge what could've been a much more expensive repair!