why don't you just buy a new one of whatever part(s) it is that control brake bias and see what if anything changes. if nothing changes then there you have it. if something does change then come back and tell us.

00 black/tan svt, #2052 of 2150, born 2/1/00 formerly known as my csvt "Nothing in the world is more dangerous than a sincere ignorance and conscientious stupidity." -Martin Luther King, Jr.