Factory stereo has power, lights come on when i turn the light switch on but it doesn't have display. i check the harness on the back of the stereo and the wire's have power going thru them i also check all the fuses in the car inside and under the hood and they all look good and test good. car has a factory amp in it. Stereo was working good before. also i swap it out with a different stereo and its the same situation.