Tilt Trimmer Problem 2005 150hp

One of my 150's is stuck in the up position. When I put my motor up after its last use last week I heard a grinding noise near the full up position (at the time I said "that can't be good"). When I went to put it down this weekend, I am unable. I've tried both the sender at the console as well as on the unit without a difference. The trim motor sounds like it is working with both trying to tilt up and down. With it in its full up "stuck" position, I opened the trim fluid reservoir and added what I could which was only a small amount of fluid. Could it be the down relay switch? Would the trim motor still run if the relay switch was the problem? Where would I find the down relay switch to test it? Any other thoughts?
Thanks,
KevinP

Its working now.

I'm not sure what happened but it is now working. I spoke with the customer service guy at Yamaha whose only suggestion was to manually lower the engine and see if it engages. I gave it a try and it worked. We'll see how long it takes for it to occur again.