Agree with brokenvert and dackel. Brake wear sensor.
if you remember, could you do me a gigantic favor? let me know if you hear a clicking noise of any sort when you drive, especially when you're in a turn. like a sprinkler, or a baseball card in bicycle spokes or something. A few of us (me included) have this problem, and neither the dealership nor an independent shop can figure out what the hell it is (thread:
http://www.1addicts.com/forums/showthread.php?t=570603). if you don't hear it, this is one more thing to cross off the list of possibilities.. i'll be eternally grateful and send you some nail clippings of my own