BMW M2 Trans Issue: Won't Start But Runs in Gear

I had very similar issues with my 2019 BMW M4 last year. The symptoms matched exactly what you're describing, rough shifting, starting problems, and the check engine light. Initially thought it was the parking lock, but my mechanic diagnosed it as an affected control unit defective in the transmission system. The repair involved replacing the transmission control module and reprogramming the entire transmission system. It was quite a serious issue that required specialized diagnostic equipment. Had to leave the car at the shop for three days while they sourced the parts and completed the work. The main problem wasn't mechanical but electronic, these modern transmissions are heavily dependent on their control units. My advice is to find a shop that specializes in BMW transmissions and has the proper diagnostic tools. This isn't something you want a general mechanic to handle. Since fixing it, the transmission has been working perfectly, smooth shifts and normal starting. Don't put this repair off though, as it could lead to more severe transmission damage if left unchecked.

Thanks for sharing your experience! It's really helpful to hear from someone who dealt with the same transmission problems. My situation seems identical to what you went through with your M4. Do you remember roughly what the repair cost ended up being? Also curious if you've had any other transmission-related issues pop up since getting it fixed? I've been worried about taking it to the wrong place, but hearing your success story makes me feel better about getting it sorted.

Hey there! Glad I could help with my experience. After getting my M4 fixed last year, I can tell you it was totally worth it. The repair bill came to 1000 € for the control unit replacement and reprogramming work, which honestly wasn't as bad as I feared it might be. The best part is I haven't had a single transmission problem since the repair, it's running like new again. The parking position issue that was giving me grief is completely sorted, and the transmission shifts are butter smooth now. I was nervous about getting it fixed too, but finding the right specialist made all the difference. Just make sure whoever works on yours knows their way around BMW transmissions and has the right diagnostic equipment. These aren't your average transmission repairs, they need specific knowledge and tools to get it right. Sounds like you're dealing with the exact same thing I did, so I'd definitely recommend getting it sorted sooner rather than later. Let me know if you need any other details about my repair experience!

Thanks so much for all the details! Actually, I bit the bullet and took my M2 to a specialist mechanic yesterday. You won't believe it, but it turned out to be exactly what you described, a faulty transmission control module. The mechanic was super knowledgeable and picked up on it right away with their diagnostic equipment. The repair was pricey but totally worth it. They replaced the control unit and did a complete reprogramming of the system. Had to leave my car there for a couple of days, but when I picked it up today, the difference was night and day! No more rough shifting, the car starts perfectly now, and that annoying check engine light is finally gone. Honestly, I'm just relieved I didn't wait any longer. Your advice about finding a specialist really paid off, they knew exactly what they were doing and fixed it right the first time. Could've saved myself a lot of stress if I'd asked for recommendations sooner! Thanks again for sharing your experience, it really helped me make the right decision.