installed new staple unit, new staple drive board with new ribbon cable and swapped out Finisher PWB, still tells me to add staples. Any Ideas?

Might want to move this question to the "in the shop" section to get an answer to your problem. This here area is for rappin and b****in.

i had the same problem it was the gray wire harness from stapler relay pcb to stapler

Have you replaced the caster's? Just messin with you.Sounds like a sensor problem perhaps. Good luck!