My Whirlpool Refrigerator has a constant dripping problem. This started a few months ago, quit, just restarted this past weekend, and now won't stop. I've replaced the filter, tried running the water to make sure no air is in the line, etc., but it still drips. Research I've done using this and other forums suggest that the water inlet valve needs to be replaced. However, other forums with different model numbers have suggesting turning off the valve to test it. If the leak continues, I am to replace the valve, if not, I'm to look elsewhere. This valve doesn't seem to have a manual on/off switch or handle to test. The part number is AP3160649, but before I spend $60 on this part, I'd like to test it. I've already closed off the valve in the basement, but the fridge still leaks.

Any suggestions for test, or am I stuck with rolling the dice and replacing the part? Thanks in advance.