BMW Massage Seat Malfunction: Stuck On/Off & Error Code

I had a similar issue with my 2019 BMW 4 Series last month. The massage seat was acting up just like yours, unusual activations and complete failures. Turned out the wiring harness under the seat had some damaged connections, and a control module connector was loose. The garage found that moisture had gotten into the connection points, causing intermittent electrical issues. They had to replace the wiring harness and reseat all the connectors. It wasn't a major mechanical problem, but it needed proper diagnosis since these seats have multiple electrical components that work together. Had to leave the car at the shop for two days because they needed to remove the seat to access everything properly. If you're getting error codes, it's best to have it checked soon before it potentially affects other seat functions.

Thanks for sharing your experience, that's really helpful! It does sound exactly like what I'm experiencing with my seat. I was worried it might be something more serious, but hearing that it was mainly wiring issues in your case makes me feel a bit better. Do you remember roughly how much you ended up paying for the repair? And has everything been working smoothly since they fixed it? I'm trying to get an idea of what I might be looking at cost-wise and whether it's a lasting solution.

Hey again! Happy to give you an update. Yes, everything has been working perfectly since I got it fixed, not a single problem with the massage function. The total bill came to 95 € which covered fixing the faulty cable connection. Pretty reasonable considering I was worried it might be something more serious! My mechanic actually managed to sort it out quicker than when I had it done before, they didn't even need to keep the car overnight. They just traced the issue to a dodgy connection in one of the plugs and got it sorted. Much simpler than when they had to take my whole seat apart last time! I'd definitely say go for it and get it checked out. These electronic gremlins can be annoying but once they're fixed properly, they usually stay fixed. Just make sure they do a proper diagnostic first, that's what helped pinpoint the exact issue in my case rather than just guessing what might be wrong.

Thanks so much for all the details! I actually took your advice and got it checked out at a new mechanic yesterday. You won't believe it, turned out my issue was pretty different from what I expected. The tech found that a loose drink had spilled under the seat months ago, causing corrosion in the control module. The repair was pricier than yours, set me back about 300 bucks because they had to replace the whole module. But honestly, it was worth it. The seat's working perfectly now, no more unusual massages during my drive! The mechanic was great too, really took the time to explain everything and even showed me the corroded parts. Funny how these things work out, I was so nervous about trying a new shop, but this experience turned out way better than my old mechanic. Thanks again for pushing me to get it checked out. Won't be ignoring any weird seat behaviors in the future!