How does a parking brake work ?

[Josh]

Yes that is broken. I cannot even move mine with my hand. make sure the bracket is tight and bolted down properly to the shaft or that it is not stripped out. That is where I would start. The next thing I would do is unscrew the piston and gain access to the inside and see what is going on. My have to just find a new caliper.

[WhiteFinish]

It appeared the screw that handles the piston when using the E brake didn't screw in really well.

Fixed that and the piston is moving out.
One side is ok when moving back the other is a bit slower.