Testing Speakers

[04nmr85]

I bought 2 sets of Polk speakers about a month ago. They're installed in my car right now but only 3 of the 4 speakers work. The one that doesn't work i'm not sure whats wrong with it. My question is: is there any way to test if a speaker is dead? If you need more info from me just let me know but since this is somewhat of a general question I figured details weren't that important. Thanks in advance!

[ktkendall]

Swap places of 2 of the speakers by putting a good one where te bad one is now, and the bad one where a good one is. If the trouble follows the speaker, then speaker is bad, if trouble stays on the line, then that output or the wire/connection is bad..