Amp won’t turn on

Hey all, I'm watching a friends car for a week, and my luck his sound system stops working on me.  Here is how it fell apart for me.

I was listening to music, pretty loud, but not to the point where anything should "blow".  I shut the car off, went inside, came back out an hour later, and now I have no sound.  I checked the amp, and the light for the amp isn't turning on now.  I was able to check all fuses, and nothing is wrong.  As far as I know, nothing has come disconnected from the back of the deck, and I know all cables are fine at the back of the amp.  I also tested the power to the amp and everything was fine.

His system is a

Head Unit: Alpine CDA-9847

Amp: Alpine V12 MRVF450 5 Channel

Subs: 2 x Rockford Fosgate P3's

And has Alpine front and rear speakers, also hooked up to the amp

Now my questions are, could I have a bad ground that came loose?

Could I blow the amp, without blowing any fuses, or speakers first, on a fairly new system?

Does the amp have a feature to reset it, or if it's played "too loud" then is there something I have to do.  I'm baffled because I didn't do anything out of the ordinary.  But go figure, it's not my car, but I do have 8 days to try to fix it.

Any help will be greatly appreciated....

Thanks,

-Sam

Ohh yes, I've also checked the obvious like the radio and cds, checked all volume, went threw head unit settings.

I checked the fuse under the hood.  The trigger wire looks to be plugged in to the back of the deck from what I can peek and see.  It's definitly plugged to the back of the amp.

Thanks Again,

-Sam.

That would be the trigger wire? Small blue wire that goes from back of the deck to the amp?