BMW M2 DCT Nightmare: Transmission Terror & TCU Troubles

Hey there! I had a pretty similar issue with my 2017 BMW M4 last year (I'd say I have some experience working on BMWs, mostly basic maintenance stuff). Those symptoms sound exactly like what I dealt with, complete nightmare with the DCT acting up. My M4 started doing the same thing, unresponsive paddles, harsh shifts, and eventually went into limp mode. Took it to my regular workshop and they diagnosed a faulty TCU (Transmission Control Unit). The whole repair, including parts and labor, set me back about 1000 Euro. They had to replace and reprogram the control unit, and it's been shifting smooth as butter since then. Definitely saved me from potentially bigger transmission problems down the line. What error codes are you getting on your M2? Also, when did these symptoms first start showing up? Might help to know if there were any warning signs before it got worse. Let me know these details and I can share more specific info about my experience.

Thanks for the detailed info! You know, I was worried it might be something catastrophic, but hearing about your similar experience with the TCU is actually a relief. My current mileage is 172306 KM and everything was fine after my last service, but this started happening suddenly last week. Getting P0711 and P0717 codes which, like you mentioned, point to the TCU. Good to know yours was sorted with a control unit replacement. Mind sharing which workshop handled your repair? I'm a bit nervous about taking it to just any shop since these DCTs can be pretty tricky. Been keeping the car in comfort mode for now to minimize any potential damage. Appreciate the help, it's always great to hear from someone who's been through the same headache!

Hey again! Just wanted to follow up on your latest message. Yeah, my M4 was actually in a really similar state when this happened, I was at around 165,000 KM. Those are exactly the same error codes I got too, which definitely confirms we're dealing with the same TCU issue. I totally get being nervous about the workshop choice, these DCTs are super complex. I actually went with a specialist BMW workshop that I've been using for years. The techs there really know their stuff when it comes to these transmissions. Smart move keeping it in comfort mode, that's exactly what I did too until I could get it fixed. Just a heads up though, even with the TCU replacement, they'll need to do proper coding and adaptation. My repair took about 2-3 days total because they wanted to make sure everything was properly calibrated. The thing that really sold me on the TCU diagnosis was that, just like yours, my issues came out of nowhere. One day it was shifting perfect, the next day it was acting like it had a mind of its own. After the repair, it's been absolutely solid, no issues for over a year now. Let me know how you get on with the repair. Really curious to hear if your experience matches up with mine.

Thanks for all that extra detail! Really puts my mind at ease hearing how similar our situations are, especially with the mileage and those sudden symptoms. Good to know I'm not the only one who's dealt with this TCU drama! I've actually found a specialist BMW workshop nearby that comes highly recommended. Going to book it in next week, your timeline of 2-3 days for the repair helps me plan better. Was a bit worried about leaving it that long, but sounds like they need that time to get everything properly sorted with the coding and adaptation. You've been super helpful with all this info. Will definitely keep you posted on how the repair goes, fingers crossed it'll be as successful as yours was! Maybe in a year's time, I'll be the one telling someone else about my smooth-shifting M2!