[asphaltgambler]

My take not knowing more information.: The pump supplies pressure and volume of fluid to the booster and steering box. It's a 'closed' hydraulic system that will bleed off any air pockets or bubbles in operation. The pump is always working when the engine is running and has a high pressure relief valve. It is a very simple design - so it either works or does not assuming you're using the correct fluid.

With the hydro-boost the assist portion for brake apply is a little more complicated but again with fluid pressure and flow it either has assist or a rock hard brake pedal.

The steering box has a recirculating- ball valving system that reacts to steering input shaft rotation. The pump is always moving fluid through the system with the engine running. If I understand your post, the assist part of your brake system is working normally. The box is not, is that correct?