I have a 1999 Cavalier and my instument panel lights wont come on at all. I have taken it to several machanics and they cant figure out whats wrong. They have changed a fuse but that caused then to stay on 24/7 and then it would cuase my stereo not to turn on. So now I dont have an instrument panel lights. Does anyone know what I should do ?

Could be a number of things. I am surprised the mechanics could not diagnose the problem. You need to obtain a wiring diagram and using a volt meter, trace the circuits. Do you have any interior lights at all? Do the parking lights work? Could be a bad switch or a loose connection behind the dash.

Could be a faulty dimmer switch..without power to that can cause them to not work at all. If not faulty then a wire has lost contact with another.