92 HVAC controls non-responsive

OK....same car - different problem.

I have push button controls that work well when they work. The problem is, they don't work until the car warms up. Once, the car is warm the controls work with no problem.

Where do I start?

Thanks.

What push buttons are you talking about?

I wonder if we have the same problem, like with the headlights.

It's the Vent, Heat, Bi-Level, Max and so on. I don't them all by name. They all have a little light that comes on when the button is pushed. It is linked with the headlights because they will dim when the headlights come on.