My pool light power supply was having issues, I could tap it and it would start working. That lasted for about 6 months. Today I took some time and my multimeter to trouble shoot the issue.
It turned out to be the fuse holder has corroded/rotted/cracked. Unfortunately the power supply doesn't' come apart and I can't replace the holder.
So for $90 I'm getting an Intermatic PX300. It should be here in a few days.
I may keep the unit, drill out the rivets that hold things together and see what I can do with it. Maybe replace the fuse holder and get it working.