So I am helping a friend do his brakes on an 08 trailblazer. Simple job replacing all pads rotors and both front calipers. One by one took everything off and put it on after bench bleeding the calipers. Made sure the front system never ran dry. Went to go bleed the fronts and I have nothing coming out. First thing I think is something is wrong with the caliper. So I crack open the actual brake line, and no fluid. I have never had to do this but I am starting to think the abs system has to be cycled. Any ideas will help, I am at a stand still right now.