Brake Booster Pressure Sensor Fault

That sounds familiar. I had a similar experience with my old Opel Astra, though it was a petrol model. The error messages weren't exactly the same, but I also noticed a change in how the brake pedal felt. The car wasn't stopping as sharply as it used to. Does the brake pedal feel different when you press it?

Yes, the brake pedal is less responsive, and I have to press harder to get it to stop. Can you tell me more about the issue you had with your Opel Astra? Any details about the error codes or how it was fixed would be great.

In my case, the error pointed to a faulty vacuum sensor, also related to the brake booster. The shop diagnosed it quickly but initially suspected a leak in the brake lines. Given your symptoms and the possibility of a bad bleed, it might be worth having a professional check the brake booster and its sensors. It could save you time and further problems.

Thanks for the advice. I took it to a workshop, and they confirmed it was a faulty brake booster pressure sensor, probably from air getting in during the brake bleed. Replacing the sensor for 90€ fixed the problem. Your suggestion really helped speed up the diagnosis.