Okay, there's a lot of things that could be wrong.

Check your ground, may have came loose. The remote wire will turn on the power indicator even if the amp is not on (crazy, I know). Do you have a Volt Ohm Meter? If so check your voltage across the amp (red lead on positive screw, black on negative) to make sure you're getting power through the amp. If you are check the speaker terminals to see if anything is coming out there. And also switch it to Ohm and check your speakers. If they are "4ohm" subs and reading anywhere above 4 or below 3.6 they're blown. If all this tests out okay then check your RCA leads going to the amp and make sure they are okay.

Narrowing down a problem like this sucks...good luck!