The ABS on my Tacoma stopped working, at first the motor would run everytime I would push on the brakes, then it stopped working, then it started working about 3 months ago, and would run everytime I pushed on the brakes, and then it stopped working about a month ago. I pulled all the sensors and cleaned them about a week ago, and they all had what looked like gear oil on them, I am trying to figure out what is going on with it. What is the easiest way to figure out what is going on with my ABS system without taking it to the shop?