I have a 2000Tahoe two wheel drive that has instrument panel problems. The battery light and seat belt lights come on, the tach, speedometer and gas gauge drop to zero and then come back up to normal. This happens for just a few seconds. The engine runs smoothly and doesnâ€™t miss. I have replaced the fuel pump, the ignition switch, the brake switch and the whole turn signal assembly. Now the door locks will not unlock when I remove the key from ignition!! Any ideas ??