I have the special key and followed the instructions (i.e. hold at right stop and turn key clockwise to increase arc). Nothing happens. I tried turning it CCW and again, nothing happens. I got the same result with all 5 of my PGPs. The instructions say when you hit the limit (either min or max arc) the sprinkler will sputter, but I didn't see this either. Although not what I needed, I was able to adjust the flow rate. Any ideas? Thanks