amp turns on and makes a small squealing noise and subs dont play

[tomvue]

Hey guys, noob here haha.

So I took my amp out yesterday and I put it back in this morning and nowthe subs dont play. I have power running in to it cause it still turns on. My ground is secured also and so are my rcas. As I put it back on today it made a small spark as I put in my ground into the amp. Negative battery terminal was removed before Installaion also. Im afraid I blew my amps internals! I checked the fuse box and its still good too! Sub wirings are also secured

[Azagtoth502]

Check everything, and always connect ground first.

[tomvue]

How can I tell if I blown an internal component or not? Also does it matter cause I mean the neg terminal was disconnected.