My impact wrench won't charge - any ideas?

Hey all, my 1/2" impact wrench (Craftsman V20, about 2 years old) stopped charging yesterday. The charger light flashes red and green, and the battery doesn't get warm. I tried a different battery and it charges fine, so it's the tool itself. Any idea what's wrong or how to fix it?

Ugh, that sucks! I've had similar issues with my drill. Sometimes the contacts get dirty. Try cleaning the charging port on the tool with a q-tip and some rubbing alcohol. Also check if there's any debris in the battery slot. Worth a shot before you buy a new one!

Yeah, cleaning contacts is step one. But if that doesn't work, it might be a bad charge circuit. I had a Ryobi impact that did the same thing – turned out a capacitor blew. If you're handy with a multimeter, you can test for voltage at the charging terminals. Otherwise, might be time to hit up Craftsman customer service or just grab a new tool. They ain't that expensive these days.

Thanks guys, I'll try cleaning it tonight. Dave, I do have a multimeter – what should I look for? I'm decent at following directions but no electrician.