I have a 1996 acura 2.5 tl.......
When I start the car the modulator makes a noise and the ABS light stays on.....But then their are days when I start the car and the modulator doesn't make that noise and the light doesn't come on,.......but I turn the car off and then turn back on and I hear the noise and the light is on..........

 

mine does this too, not sure why. i just pulled the fuse and called it done.

 

i was going to pull the fuse but now as i stop at a light my brake pedal gos down to the bottom

 

Your brake master cylinder has gone bad.