The headlights on my 1995 Jeep Cherokee Country will not come on. All the fuses are good and the relay in the main fuse box (under the hood) is good. I can pull back on the dimmer switch (to bright) and they will come on but the switch will not lock into the bright position as normal, once the switch is released the lights go off. My tail lights, parking lights and brake lights all work. When this happened I was driving at night. The headlights flashed several times then went out.