The imbalance he is referring to, is the "Pressure" to your front brakes may differ from the rear brakes--- one way of looking at it would be, there is a problem along the way, as pressure reaches both--The pressures being unequal--turning on the light. On older stuff, this might be the case if the "Divided" brake fluid reservoir was empty on one side or a problem with the Proportioning valve (where the "unequal switch" is located), or maybe a crimped brake line.
Your reservoir is not divided, until its about empty, then fluid will go to the front brakes or the rear (reason the aluminum part has 2 holes sticking up, that the reservoir snaps into) If your reservoir has fluid, and holds it, then you are not empty on the front or rear system.
I have one other EZ thought to throw in, then wrenchtech will have to keep it going.
I just went to Advance Auto On-line and looked at your master cylinder assembly.
Inside the reservoir, is a float or a similar item, it moves up and down as the fluid moves up or down. When it reaches the bottom, usually from a "Low Fluid" issue, the light comes on.
In other vehicles I have seen the float may get "Stuck" at the bottom, or might get "C. Ocked", and in a bind, unable to rise up as fluid was added.
One other scenario I saw once, was a friend hit a really hard bump, the float bottomed out and it did bind at the bottom.
The way we fixed the issue was, at first, tapped on the reservoir to knock it loose. That did not work! With a small screwdriver, he went thru the cap and sorta pushed on the float and released it, it then rose to the top and his light went off!
Maybe it's that simple for you too.
Monday, May 23rd, 2011 AT 5:50 PM