I'm not too familiar with the OMC Cobra systems but if they are like the Merc stuff here what i would start with:
First thing i would check is if the fuse is good! (If it has one)
The next thing to check would be if there is power getting to the Trim motor? Get a volt meter and check the power leads and make sure the ground is also connected good with no corrosion around it.
Have someone activate the switch and another listen next to the pump. Does it "Click" when the switch is depressed? That would be the solenoids activating for the pump to go either up or down. If thats working then more then likely the pump itself is bad. If you hear no "clicking" then maybe the solenoids are bad. This would be the esiest to start with. You can even go to a local electrical motor rebuilder and they should be able to rebuild it for ya for not so bad a price. http://free.***boat.net/ubb/biggrin.gif Hope that helps
-Wally