2011 Dodge Ram 1500

2011 Dodge Ram 1500 4.7 the issue I am having is
that my truck when I turn it on cold start . The radio
heat and other accessories turn off . For about a
minute ... I replaced the alternator because befor it
was doing the same but my lights on dash would
turn on and then turn off . And then my heat and
radio accessories would. Work relplaced alternator
and no lights on dash turn on but the heat and
radio and accessories continue to turn off as I cold
start the truck