BMW 4 Series ABS & Traction Issues: Sudden Jerking Help

Hey there! I have some experience working on BMWs, and I dealt with almost the exact same issue on my 2015 BMW 3 Series (also had a 5 Series before). The symptoms you're describing sound identical to what I experienced. My ASC and ABS were completely dead, and that annoying jerk during acceleration was driving me crazy. Took it to my trusted mechanic, who diagnosed it as a faulty ASC relay. The fix was pretty straightforward, they just replaced the relay, and everything went back to normal. Cost me about 90 Euro total. Before you head to the shop though, could you share: How many miles/kilometers are on your car? When did these symptoms first appear? Are there any other warning lights on? This info would help confirm if we're dealing with the same issue. BTW, if it is the relay, it's a relatively simple fix that shouldn't break the bank.

Just had my last service done about 2 months ago at 172025 KM. My symptoms started pretty out of nowhere last week, was just driving normally when everything went haywire. Besides the ASC service light, I'm not seeing any other warning indicators. Really appreciate you sharing your experience! That relay issue definitely sounds similar to what I'm experiencing. Kind of relieving to hear it might be something relatively simple and not too expensive. Guess I'll get it checked out soon, fingers crossed it's just the relay like in your case!

Hey again! Thanks for providing those details about your BMW. You know what, that's pretty much exactly how mine started acting up too! The timing after your service and the sudden onset really makes me more confident it's that relay issue I mentioned before. Mine also went crazy out of nowhere, perfectly fine one minute, then bam, everything started acting up. And just like yours, my only warning light was that ASC service indicator. The mileage is pretty similar too, mine was around 165000 KM when it happened. Quick tip from my experience, when you take it in, make sure they check the wiring around the relay too. My mechanic found some slight corrosion on the connectors, and cleaning those up helped ensure the new relay worked perfectly. Might save you from having to deal with this again down the road. Still sounds like it should be a pretty straightforward fix. Let us know how it turns out when you get it checked! Always good to hear if our experiences match up in the end.

I'll write the final response Thanks so much for the additional info and that great tip about checking the wiring! It's really reassuring to hear our situations match up so closely, same sudden onset, similar mileage, and identical warning lights. I've actually just scheduled an appointment with my mechanic for tomorrow morning. I'll definitely mention the relay and ask them to check those connectors for corrosion too. You've been super helpful, and I feel much better about the whole situation now. At least I won't be walking in completely blind, and it's good to know it's likely not something major. I'll definitely update this thread once I get it sorted out, might help someone else with the same issue down the line. Thanks again for taking the time to share your experience!