[jadnashuanh]

The manual says if the brakes fail, to pull up the parking brake switch and hold it. I know it works when everything else is working, but the engineer in me wonders how the thing actually is working. Does it have an accumulator and uses pressure from that on the service brakes?

FWIW, I put about 1100km on mine and am waiting it to be shipped from Germany to the US. At maybe 300km, the system announced the parking brake had failed. Since the vehicle still moved and wasn't locked down, I drove it. Shortly after, the warning went out, and never came back on while I had it and worked fine. But, wondering what failure mode triggered it. I had dug out the manual to see about the manual release, if needed (and boy, does that look like a pain, especially if the trunk is full of stuff), but luckily, didn't need to deal with that, since the vehicle did move easily.