I have an 06 Saturn Vue. The battery tested out good as well as the aftermarket alternator. However

Sass

At temperatures under 50 degrees, all of the lights flash, the radio quits working until it reaches operating temperature. The battery has now been replaced and it starts fine. ( still has the possessed blinky thing) we pulled the fuse on the radio before replacing the battery to see if that was where the battery drain was coming from. Anyway, I replaced the fuse, the radio doesn't work and now that I have replaced the battery, a light comes on that says my battery is getting hot. Any ideas?

PF_Flyer

It's possible your serpentine belt is slipping on the alternator pulley and you're not getting full output from the alternator.