Lost electrical power to trim solenoid.
 

I installed 2 new trim solenoids on my port side, work ok for a short time, then I loose electrical power to solenoids. I have remove the connections and clean and reinstalled, worked fine for few hours and stop working again. Anybody have any suggestion where to look for other possible problems?

found the problem.
 

I checked all my wire connections from switches to pumps, also checked the relays in the black box (dual power trim system) and check- out ok! I decided to check all my connections on the trim solenoids again for the 4-6 times, connections ok, I then put a test light and voltmeter on the 110 amp fuse next to the solenoid, ( big surprise!), the positive wires connected to the fuse is 12v, but the volts coming out of the fuse was so low that the test light was very,very dim. I tested the starboard 110 amp fuse and voltage on both side of the fuse is correct, so I took that fuse and put it on my port side to test, my outdrive went up and down with the trailer switch and throttle mounted trim switch. I spend many hours testing, I'm so happy to find out what the problem was, hope this information help other people with power trim problems.