Wow…you’ve got the last Mohican there.
6” to 8” is the door zone. I think US used an 8” vane way back. So I’d be looking at the dropping of High Speed (H)
but before DZ picks regardless of direction. Something has to hold the direction in until LU or LD. IIRC, DZ normally closed (out) is what holds in direction until LU or LD then DZ. Stepping Up or Down or dropping High would occur at about 30 inches from FL on a standard 125fpm job. The boards Hydro 1 and 2 also carry signals from the car to the controller. So yes the correct print would show those inputs as well.
Also, those reflector bulbs each have a receiver too so it could be DZ receiver is dead. If the car is on car top inspection, and you stick the vane on LU or LD then flip to RUN, what should happen? It should level into the floor. If it oscillates up and down, it’s not seeing DZ.
Keep us posted on the outcome.
Last edited by elmcannic; 05/02/23 05:00 AM.