BMW iX2 Brake Booster Issues, Symptoms and Solutions

Hey there! I had a pretty similar situation with my 2022 BMW iX3 (I also own an iX1). I'd say I have some experience working on EVs, though I'm no master mechanic. From what you're describing, it sounds exactly like what I dealt with last month. My brake pedal felt spongy, and I was getting those same warning lights. Took it to my regular workshop, and it turned out the brake system wasn't bled properly during the last service. They had to do a complete brake system bleed using their diagnostic computer. Cost me 90 Euro, but it fixed all the issues, no more warning lights or weird noises. Before you go that route though, how many miles/kilometers on your iX2? When was your last brake service? Are you noticing any fluid leaks under the car? This info would help nail down if you're facing the same issue I had.

Thanks for sharing your experience! I've got 102503 KM on mine and just had the major service done last month. No fluid leaks that I can spot, and everything was fine until these symptoms started showing up a few days ago. The brake pedal definitely feels different than normal. Good to know about the bleeding issue you encountered, makes me wonder if something similar is happening here. Did your brake pump also make those weird noises before you got it fixed?

Ah yes, I remember dealing with this! Absolutely, my brake pump was making those exact same noises, kind of a whirring sound, right? It was super annoying, especially when I'd first start the car or when braking at low speeds. Since you mentioned you just had major service done last month, this is sounding even more similar to what I experienced. My issues started about two weeks after a service too. I initially thought it was the pressure sensor (like you mentioned in your first post), but it turned out the air in the system was the culprit. The pump was working overtime trying to compensate for the poor bleeding job. Quick question, when you press the brake pedal, does it feel like it goes down further than usual before engaging? That was another symptom I had that really convinced my mechanic to check the bleeding first before replacing any parts. Just a heads up, if it is a bleeding issue like mine was, make sure they use the proper diagnostic equipment for the bleeding procedure. These new BMW brake systems are pretty sophisticated and need the computer-controlled bleeding process to get all the air out properly. Don't let them try to do it the old-school manual way. Oh, and keep us posted on what you find out! I'm curious to know if it's the same issue I had with mine.

Thanks so much for all the details! Yes, that's exactly the sound, a whirring noise, especially noticeable at low speeds! And you've nailed another symptom, the brake pedal is definitely going down further than normal before it catches. After hearing your experience, I'm pretty convinced it's related to the bleeding now, especially since the timing lines up with my recent service. I'll take it back to the shop tomorrow and specifically mention the bleeding issue. Really appreciate the tip about making sure they use the proper diagnostic equipment, I'll definitely bring that up. Honestly, I'm relieved it might not be the pressure sensor, as that would've been a much more expensive fix. I'll update the thread once I get it sorted. You've been super helpful in pointing me in the right direction!