Brake Light On problems of the 1997 Buick Regal

At low speeds (under braking conditions), brakes make loud grinding noise and completely fail to stop the car. Abs light, low tracking light and engine check light came on/off. We have had 14 instances where the brakes have completely failed. Approximately 5 seconds after initial failure, the brakes come back. We have taken the car to the dealership 8 times so far, and they have not been able to correct problem. We have called the manufacturer to report the problem (case#990045360). Various brake warning lights continue to illuminate, even when the car is not moving and we are not applying the brakes.