I can't speak specific to the Pioneer but I would imagine it's a similar process to any other mechanical brake system. When you bleed brakes, you start with the brake assembly furthest from the master cylinder and work your way to the one closest to the master cylinder.
Unless you have an attachment on your bleeder screw (available at most auto stores), it's usually a two-person job. One person will pump the brakes several times and then hold the pedal down. The other person opens up the bleeder screw to let the air and fluid mixture out. Be sure to tighten up the bleeder screw before the person releases the brake pedal so air is not sucked back into the line you're attempting to bleed.
Repeat that process until just fluid comes out of the line. Then, move on to the next bleeder screw that's the furthest away from the master cylinder. Also, keep tabs on the master cylinder so that you don't run it dry in an attempt to remove air from the brake lines. If that happens, you're going to have to start all over.
Jerry B.
