Based on my experience, when I have my ABS light come ON, I was not able to clear it. However, disconnecting the Battery cable and disconnecting the ABS electrical connections overnight cleared the ABS light. Bleed the brakes, cleaned the wheel speed sensor on two front wheels and the ABS light would come ON once in a while. Come to find out that for some reason, the problem is related to failing alternator. It had me stranded with dead battery. Replaced the alternator and charged up the battery and I did not have ABS light coming ON/OFF for no reason anymore.
A few months ago, my other car started to light up the ABS once in a while for no reason while driving straight. I went immediately to Autozone, to check my alternator and battery. You don't need to remove the alternator and battery, they can check your battery and alternator while it is still in the car. Sure enough, the alternator was failing and I've replaced and I have not any ABS light coming ON for no reason.