How do you test solenoids? If you want to check and find out which one is messed up, i got three per pump for example. I know its a solenoid, because batteries have been tested and all are good. I get a click when i hit the rear switch and that's all. I would assume no one replaces all three, there must be a way to check one by one to see which one is stuck. Anyone want to give me a how-to???