BMW M4 Air Suspension Failure, Low Ride & Power Loss

Had the exact same problem on my 2016 BMW M3 last year. The symptoms matched perfectly, low ride height, warning lights, reduced power mode, and misaligned headlights. Turned out the wiring harness connecting to the air suspension control module was corroded and had some loose pins. The mechanic found that moisture had gotten into the connector, causing intermittent connection issues. The fix involved replacing the entire wiring harness and connector assembly. It wasn't just a simple plug-and-play job since they had to route the new harness through some tight spaces. Definitely a serious issue that needed immediate attention, as it affects multiple vehicle systems. Would recommend getting it checked ASAP since driving with reduced power and misaligned headlights isn't safe. The compressor might not be the culprit, get the electrical connections checked first.

Thanks so much for sharing your experience! It's really helpful to know that you faced the same issues with your M3. My symptoms are identical and I hadn't even considered it could be the wiring harness, was totally convinced it was the compressor. Good call on getting it checked quickly, you're right about the safety concerns. Would you mind sharing what the repair ended up costing you? Also curious if you've had any other issues pop up since they fixed it? Want to make sure I'm prepared for what's coming.

Hey again! Great news, I actually just got my car back from the mechanic last week. You'll be relieved to hear it was definitely worth checking the electrical connections first. Turned out it was just a faulty cable connection to the air suspension compressor, much simpler than replacing the entire unit. The total bill came to 95 € which was a massive relief, I was mentally prepared for something much worse! Since the repair, everything's working perfectly, the car maintains proper ride height, no more warning lights, and the headlights are properly aligned. Engine power is back to normal too. Haven't had a single issue since the fix. It's amazing how such a small electrical problem can cause so many symptoms across different systems. This experience has definitely taught me not to immediately assume the worst (like needing a new compressor). If your symptoms are identical to what I had, there's a good chance you're looking at a similar straightforward fix. Much better than having to replace the whole compressor unit!

Just got back from the mechanic and I can't thank you enough for your advice! You saved me from a potentially expensive mistake. Like you said, it was an electrical issue, a damaged wire near the compressor that was causing all those problems. The repair bill was pretty reasonable, around 120 bucks. The mechanic said I caught it at the right time before it could cause any serious damage to the compressor itself. Car's running perfectly now, back to normal height, headlights aligned, and full power restored. Funny how things work out, I was so convinced I'd need to replace the whole compressor unit, was dreading a massive repair bill. Really glad I asked here first! This whole experience taught me not to jump to worst-case scenarios. Sometimes the simplest explanation is the right one. Thanks again for steering me in the right direction. My wallet definitely thanks you too!