The pedal goes to the floor and you didn't recognize that as a problem?
If there's no external leaks and the level is good in the reservoir, suspect internal leakage in the master cylinder. It can be replaced without having to bleed the system at the wheels. When you can't build pressure in half of the hydraulic system, the pressure differential valve shifts in the combination valve and the switch turns on the red warning light.
SPONSORED LINKS
Sunday, May 26th, 2013 AT 2:18 PM