BMW M2 Transmission Woes: Sensor Issues and Limp Mode Fix

Hey there! I've got some experience with cars, not an expert but I've dealt with similar issues. I had this exact problem with my 2014 BMW M4, and my cousin actually owns an M3 too. The symptoms you're describing sound really familiar. In my case, it turned out the gearbox oil level was too low, causing those rough shifts and warning lights. Had to take it to the workshop where they did a proper inspection and oil level check. The whole thing cost me 365 Euro, including labor and new transmission fluid. My car was in the shop for about a day and a half, and it's been running smooth ever since. Before you do anything else, could you share: Current mileage? When was the last transmission service? Any other warning lights showing up? This info would help me give you more specific advice based on my experience.

Thanks for sharing your experience! Currently at 102181 KM and last service was about 2 months ago. Had my transmission fluid changed then, so I don't think it's a fluid issue. The strange thing is the problem started suddenly during my morning drive. No other warning lights except the transmission one. Based on what you're saying, my issue seems different from yours. The grinding noise is really concerning me though. I'm gonna have to take it to a shop and get that sensor checked out. Hopefully it's just the sensor and not something more serious with the transmission itself.

Hey again! Yeah, after hearing your mileage and recent service history, I'm definitely thinking your issue is different from what I experienced with my M4. The sudden onset and that grinding noise does point more towards a sensor problem, especially since you just had the fluid changed. You know what's interesting? After I shared my low fluid experience with you, I actually ran into a similar sensor issue about 6 months later. My transmission temp sensor went bad and I got those exact same symptoms, the grinding, rough shifts, and that annoying warning light. The repair cost me around 450 Euro, mainly because they had to remove some components to access the sensor. The good news is it was a relatively quick fix, my car was back to me the next day. The bad news is that if you leave it too long, it can cause more damage to the transmission. I learned that these sensors are pretty critical for protecting the gearbox. Since you mentioned you're taking it to the shop, I'd recommend having them check the wiring harness too. Sometimes it's not the sensor itself but the connections that go bad. Found that out the hard way when my cousin's M3 had a similar issue. Let me know how it goes at the shop. Really curious to hear if it turns out to be the sensor like I suspect.

Thanks so much for the detailed follow-up! That's actually really reassuring to hear about your sensor experience, sounds exactly like what I'm dealing with. I'm glad you mentioned the wiring harness too, I'll definitely ask them to check that. Makes me feel better knowing it might not be as serious as I initially thought. I've already booked it in for tomorrow morning, and based on what you're saying, hopefully I'll have it back by the next day. That repair cost doesn't sound too bad either, I was worried it might be thousands. I'll definitely update you once I get the diagnosis. Really appreciate you taking the time to share your experiences, especially since you've actually dealt with this specific issue. It's always nerve-wracking when these performance cars start acting up!