Still brain storming here.
I was fighting a problem a while back and found the wire loop going to resistor door would press in the Potter brumfield relays, with resistor door closed, but I think in my case I think it caused the elevator to stall.
I have also heard of shorts in ribbon cable to logic door causing issues like you describe. But keep in mind, these are long shots.
Its also possible that there are pins touching together on the back side of an IBM relay or ribbon cable terminal block. These terminal blocks are tightly packed and located on the logic door and up on the selector. They are labeled A, B , X, Y, etc.. If someone changed a ribbon cable in the past without proper pin removal and insertion tools , it easy to bend the metal portion enough to touch the neighboring conductor, much less easy to miss wire a single conductor on these terminal blocks. I use a non conductive orange peeler stick to make sure that pins that look a little too close aren't actually touching.
I also wonder if it might be worthwhile to swap optical leveling card with another unit. I wouldn't be concerned about level sensors , because that would just cause failure light to turn on. But perhaps an output component on this card is getting stuck on. These are easy to swap.
