Does it light up like it is on but no sound? If so 1 of your speaker wires in the car just could be touching metal and that would put the radio into protection shutting down the onboard amp 1 wire is all it takes to any speaker , or a loose speaker with the terminals touching metal , if it lights up and no sound like someone else said remove it hook it to the battery and use 1 speaker to check it.
if it doesnt even light up its done.
if you have 10 speakers in parallel hooked to it and ran the wrong ohmage to it you could have a fried deck .

Best wishes , lol