Ford Taurus Forum : “97 taurus dash break light on when i stop, goes off while driving. what could be...”

The first thing you check is the brake fluid level Sim. If it is low you can refill it and the light should stay out. Even if that works you should have your brakes checked to see why fluid is leaking. Other problems could include faulty sensors (unlikely if the light doesn't stay on) and issues with your ABS system. If your brake fluid level isn't low, or if the light doesn't stay off when you fill it, you need to have a pro go through your brake system for you. Good luck!

I have the same problem and I think it is the brake vacuum check valve to the brake booster.  It is defective and when I accelerate at a certain speed the light goes off.  Meaning the vacuum from the manifold at a certain speed over comes the lack of vacuum in the booster which should have built up and held. I also have a harder brake pedal and crummy idle,stalling ect. I think it is not your ordinary  check valve either,because I can't see it unless I start tearing apart the console or moving the master brake cylinder. Is it that funny looking box that four hoses of various sizes converge on the dash? Bob.