A mis-wiring or short circuit somewhere between the controls, fusebox and lights.
When you turn on the headlights of any car it causes a load (or horsepower drag) on the engine. Your car has an idle problem and the load on the alternator simply exacerbates it.
I've heard that if you have an automatic light switch sut-off switch and are having problem with your headlights flashing like a police car, it was caused by the cars computer.
a flat battery
It's possible that the fact that it's light or dark has nothing to do with your headlight working or not working. Look into other causes of the problem: Such as: Is is wet outside?, How about overheating of the components surrounding your headlights?
Probably your alternator.
I think it is a dying battery
What_is_a_loud_humming_from_car_light_motor_after_in_lowers_down_and_closes_on_your_1997_firebird
It has a bad seal or a crack allowing moisture to get in.
its to conserve power to start veh. with full voltage to starter headlights will come on after starting car
I had the switch assembly on the steering column get burned-up at it caused my headlights to go out. It cost about $250 to replace.
Capsizing causes the most fatalities.
Capsizing causes the most fatalities.