A Klasse brake booster pressure sensor issue

That sounds tricky. I had a similar issue with my A Klasse. Does the error appear immediately, or after driving? What brake work was recently done, and were any parts replaced?

The error appears after about 10 minutes of driving. The brake work was just a routine pad replacement. I'm unsure if anything else was touched. Is this a serious issue, like a potential brake system failure?

The delayed error is interesting and similar to my experience. With hydraulic brakes, it's hard to know without a diagnosis. Given the vehicle safety implications, I advise a professional check. They can pinpoint the problem.

I took it to a workshop, and you were right. It needed a new brake booster pressure sensor and a system re-bleed. The cost was around 90€, but the car stops properly now. Hopefully, that resolves it.