Sony xpold amp has no power

Question

i just bought a xm1252gtr sony xplod amp.800 watt output..conected it to my 12' sony xplod sub..the lighds came on and everything, worked perfectly fine, then all of the sudden it turned off and hasnt came on since..any ideas??it is as though there is no power running to the amp but all the cables are wired up correct and the ground wire is fine