Not trying to resurrect an old thread, but as this is one of the first ones that comes up when you search E70 Parking Brake Actuator, I want to say thanks by adding a few items.

First thanks to DarkMesa8 for the original post. It allowed me to do the repair in a couple of hours.

Mine had the negative spade on the motor broken clean off. Simple problem, not really an easy fix. There is small hole next to the spade. I used a small drill bit to enlarge it, then pushed a wire inside (next to and in contact with the broken spade), then soldered it. Not pretty but it seems to have worked.

https://photos.app.goo.gl/MYTaT3H4Fobj7GxZ7

2nd Tip - The Ebrake reset procedure.

I have seen it a few times online and on Youtube. For my X5, it only works when in DRIVE. I tried it a bunch of other ways: Ignition on, engine off, foot on brake. Engine on, tranny in Park. Unhooked the battery for an hour. Nothing. I could get the park brake to work while driving, but still had the error, until I tried doing the reset procedure in Drive, foot on the brake pedal. It cleared the dash error after holding the switch down for 5 seconds.

On a side note, using bimmergeeks ProTool, I did not have any parking brake codes stored in the module once clearing it after the fix. But still had the error as soon as the truck woke up.

Hopefully this will help someone else out.
Steve