Please help! Electrical problems!

I had this problem last spring then it went away over the summer. Now it is back. My keyless entry will not work. The door locks will not work. The heater works only on high fan ONLY WHEN THE HEADLIGHTS ARE OFF!!! If a door is opened the heater turns OFF!! The heater panel lights, nothing else, stay on after I get out (the interior lights don't come on) but when the interior lights would normally shut off on their own the panel lights go off. I really need headlights & defrost at the same time. It is hard to drive in the snow w/no defrost! Any ideas?? I need help. Thanks

you most likely have some wires spliced to wrong places