The yellow brake light just indicates that abs is off (anti-locks) but your brakes will work in non-abs mode. I have had this happen before when I trick the abs into thinking it's not working by running over a manhole cover while braking hard. The manhole cover would move with the wheel and the wheel would appear to be in a locked position making the abs system think that something is wrong. It would go into a fail safe mode of turning off abs all together and allow the car to work with standard braking.

By turning off the car and then turning it back on... this resets the abs system and the yellow light would/should go away.