The process of turning off and resetting the ABS light will vary from one car to another. For example, in a Toyota, you'll first have to remove the negative battery cable. It should drain any residual power left in your car, while also resetting the computers. Then, wait a few seconds, and re-connect the negative battery cable back to the battery. In so doing, that should be enough to reset the entire ABS system, and the ABS light should now be off the next time you start up your car. However, if the ABS warning light does come back, it might indicate that something's wrong with your brakes.