Blew up alternator and now no stereo

[vn50L]

Hey guys. Got my mrs to help me change a battery on Saturday morning and she whacked the terminals on backwards. As soon as she did a big plume if smoke came out if my alternator (which was stuffed anyway hence the desperate battery change). I've since replaced my alternator and now my head unit won't turn on. Is it likely a wiring issue or would the head unit itself be stuffed? And why would my alternator burn up like that?

I should add my auto electrical experience consists of changing fuses and globes and I'm a bit of a spastic in the area. I have a few other possibly related gremlins as well and my sunroof **** itself recently and I'm thinking the cause may have been a voltage spike.

Thanks guys and gals.

Pete.

Oh btw it's a Vt series 2 xu6.

 

[Nic92]

check the fuse on the head unit and check all the fuses under your steering wheel and in the engine bay

 

[KAL SPL]

Factory or after market unit ?

 

[vn50L]

After market. Just some JVC thing. Hopefully its stuffed, needed an excuse to get a new one. Still cant work out why putting the battery on oposite terminals fried my alternator? worried it means something else is amiss.

 

[lout]

Diodes block power in one direction and allow full current flow in the opposite direction
connecting battery backwards nearly always takes out alternator and radio

 

[vn50L]

Thanks for that man. Guess I'll stop worrying about it. So should I assume the head units stuffed??