Went to start my impala the other day and it was dead. Started charging the battery and the heat in the cabin kicked on without having the key in the ignition and being turned off on the manual switch. Also the radio turned itself on which is an aftermarket kenwood I installed myself. I've read around and found a few things it could be HVAC fuse, heater module under the glovebox is fried or ignition switch problems. Prior to this I've also been having the GM passlock problem where my car decides not to start for an unspecified amount of time. Not sure if the two are related but I'd like to figure this out so I can go to school! Any help would be appreciated thanks in advance.

Nate