Diagnosing bad Bennett Pump

Hey guys new to the forum, just picked up an 02 Launch SS that has a non working wake plate pump (I think). Gauge does show a reading but no physical movement of the pump when switch is activated. I searched prior to starting this thread and found a few posts that related to my situation but they did not describe the outcome, just stating relatively the same problem (wake plate not working). Boat has 270 hours on it obviously has sat a lot, previous owner said it just didn't work at the beginning of the season in 09. To get to the point - is there a procedure to follow starting with the commonality and then down the chain of possibilities? I've seen there's a link to the Bennett site and read that they have great service but I would rather get the necessary info here seeing as how it's been a common problem from the looks of it. Experience is always very helpful so please don't be shy any and all help is appreciated!

Zach