Yeah, trust me I've tried it all. I've gotten probably 10-15 wiimote at thrift stores on the cheap, all of them store returns from Target or wherever. Most there is nothing wrong with at all, I figure the person who bought it just didn't know how to sync it, so returned it as defective. The store can't sell the open item, so they just mark it defective and donate it.
In the case of these 3, I could not get blue lights no matter what I tried (including the red button, of course). One I opened up looking for solder splatter and a couple other potential issues I read about, but no joy. The first one I got a replacement from Nintendo for w/ no questions asked, but the last one they wouldn't do anything for me on (anyone want it?). I paid 2 bucks for it, so no biggie. I wouldn't pay 15 bucks for one now without testing, except that Goodwill has an excellent return policy, so no risk.