Chased2, what achris is saying is that the one power wire that goes to the switch on your throttle powers both up and down. If down is working but not up, you don't have a power problem going to your switch.
The switch having what feels like two stages means that the lower pressure is trim up, the higher pressure is trailer mode. I have this type; you press up lightly to trim the motor, you press it firmly to lift it to trailering height. The limit switch on the transom shuts the pump down once the upper limit is reached for boating, but the higher pressure bypasses that switch and allows the outdrive to be raised all the way up for trailering. If it goes up to trailer height, it's the limit switch on the transom. If it doesn't move no matter which stage of pressure you've applied, it's the switch on the throttle.
If it is the trim limit switch, make sure the screws haven't backed out and the switch has moved all the way to one side. If it's too far out of adjustment it won't trim up because the limit switch is so low it thinks that bottom is the upper limit.
Edit: also check and make sure you're connections are good at your solenoid and whatever tool you're testing with. That's quite a bit of sealer on those connections and you may be getting a false negative or a bad connection. All this is for naught if the solenoid is actually the culprit, and they do fail as I just had to replace mine for an intermittent trim up failure.
