BMW 6 Series AC Failure: Ventilation System Diagnosis Needed

Hey there. I faced a similar issue with my 2016 BMW 5 Series diesel last summer. The symptoms were almost identical, AC wasn't cooling and the ventilation system was acting weird. After taking it to the garage, they found it was a faulty connection between the climate control module and the flap actuators. The wiring harness had some corrosion and one of the plugs was loose. The mechanic cleaned the connections, replaced a damaged section of the wiring, and recalibrated the system. Wasn't a major repair in terms of complexity, but it did take them a few hours to diagnose and fix properly. The tricky part was accessing the components behind the dashboard. They also recommended checking the refrigerant levels while they were at it. Since the fix, the AC and ventilation have been working perfectly. These electrical gremlins can be annoying but aren't usually serious mechanical issues. Just make sure you find a mechanic who knows BMWs well, the diagnostic system is quite specific to the brand. Hope this helps with your decision.

Thanks for sharing your experience! That's really helpful info. My situation sounds pretty similar to what you dealt with. Quick question, do you remember roughly how much the repair ended up costing you? Also, has everything stayed working properly since then, or have you noticed any other climate control quirks popping up?

Hey again! Yeah, actually I just got my car back from the mechanic last week, it was exactly what I suspected based on my previous experience. The total bill came to 95 € for fixing the cable and plug connection issue with the rear ventilation flap. Pretty reasonable, if you ask me! Everything's working perfectly now, the AC's blowing nice and cold, and the rear ventilation is functioning just like new. It's such a relief to have it sorted. Since my last repair on the 5 Series, I haven't had a single problem with the climate control system. These BMWs are solid cars once you get these little electrical niggles sorted out. Just keep in mind that finding a good BMW specialist is key, they know exactly where to look and what to check, which saves time and money in the long run. My mechanic mentioned these connection issues are fairly common in BMWs of our vintage, so at least it wasn't anything out of the ordinary. Let me know if you need any other info about the repair. Always happy to help a fellow BMW owner!

Thanks so much for all the detailed info! Just wanted to update you on what happened with my car. Finally took it to a mechanic who specializes in BMWs, and you were spot on, it was mainly connection issues. The repair was actually cheaper than I expected, around 120 € including parts and labor. Had to leave the car for a couple of days because they were backed up, but it was worth the wait. They found a corroded wire in the ventilation system and a slightly damaged connector. Fixed those up, recalibrated the system, and now everything's working perfectly. The AC's blowing cold again, and the rear vents are working like new. Really glad I asked here before taking it somewhere unusual. You saved me from potentially spending way more at a general mechanic who might not have known exactly what to look for. Fingers crossed it stays working well like yours did! Thanks again for your help, really appreciate you taking the time to share your experience!