[beachBmmr]

Originally Posted by Hawkdog

Besides getting MY car fixed, that’s the other reason I wanted to post this despite making myself look like an idiot. I’ve bled brakes on dozens of cars over the years and know what I’m doing for the most part. Was hoping this thread might save someone else from the fun. Still hoping someone can come along and read what I did and shine some light on why the car did what it did.

The car has an electronic master cylinder and is brake by wire. Opening the bleeder valve and bleeding confuses the computer. So does leaving the caliper pistons retracted and starting the car.

You might be able to do this manually with the car totally off but you will likely get a critical brake warning and lose brake assist as the car sees the fluid pressure change and thinks theres a leak.

happily, You can clear the errors with bimmer link.