hi. i have a 2010 aveo5 with 60,000 on the clock. just heard a clicking noise coming from outside (i had the window closed) and i think it might be the metal thing on the brake pads they call a sensor.it's supposed to make a noise when the pads wear down far enough. the ones on my chevys would squeek and this one was clicking. am i on the right track or do you think it might be something else? the original pads are still on the car. as allways thanks very much. denny