No power steering - pump or box?

00 cherokee, 96 engine, new steering lines. Had power steering but haven't driven much, only around the block. Slop in steering so I swapped in a durango box. Had power steering after swap but again drove around the block, let it sit a week or so, started up and no power steering. Flushed fluid, checked lines, still nothing. No noises from pump indicating failure, when flushing system I removed return line from reservoir, and I would really only get fluid coming out when steering was turned at full lock.

How do I know if its the pump or my steering box, or ?

If you only get fluid out of the return when the box is operated, then the pump is not working