All lights & signals work fine, but on the dash; the brake, brake booster, abs and battery lights remain on. The heat/air does not blow when turned on, and the radio does not work. The battery seems to be strong and they're not that old (2 months). The smaller 2 prong fuses are all ok. all the large fuses are good (that i can find), the alt. is charging, al the lights will go out and everything works fine if i am going 50-55 mph or race the eng. fairly high.wat could it be?