What game is it? Can you post a schematic, or is there one online at IPDB?
Quoted from Schamattack:When at 0 all three switches are fully open. When at 1-8 they get a tad closer together but do not reset.
If there's no difference between the 0 position and the 1-8 position something's not adjusted properly. At least one of those switches should close in the 1-8 position. To determine which one you could close them one at a time, preferably with an alligator test lead clipped to the solder lugs, then see if it resets as it should.
/Mark