Chances are there is a leak in one of the lines. Pad and lining wear is not an issue. First of all, watch your parking brake light very closely with the engine not running. If it gets the very tiniest bit brighter when you apply the parking brake, that is not the reason it is on. Next, unplug the fluid level sensor in the master cylinder reservoir. If the light goes out, add more fluid or check if the float has sunk. Finally, unplug the pressure-differential switch in the combination valve. It's near the frame under the master cylinder. If that makes the light go off, the valve is stuck in some corrosion. It's spring-loaded in Chrysler and GM vehicles. A good jab on the brake pedal after the leak is repaired will usually unstick it.
If you have the "newer" master cylinder with four steel lines coming out of it, let me know as there are some important differences, but that system is usually used only on front-wheel-drive cars.
Thursday, February 17th, 2011 AT 2:55 AM