Oldsmobile/Buick Repair: 1998 Buick Regal, buss bar, buick regal

Question
I have a Problem withthe heating control in this car. It seems to work fine when the weather is above 40 degrees. Anything lower than that the heat stops working and the interior dash lights get bright, and sometimes the headlights flash on and off. I have had this vehicle in the shop 4 times,I have put a new blower motor,and a board behind the dash that was Burnt out the first time. That is still good however I still have the same problem when it is cold. I really do not have any repair History on this vehicle. I have only had it 40 days.  Any Suggestions?

Answer
Hello Cynthia,
I don't work on that system, but I would look for loose connections, especially ground wires.
Up under the dash there is a little buss bar with multiple ground wires connected to it. Make sure all the connections are good, but especially the one that connects all of them to ground.

Van