ABS Light with no code

My ABS light has been going on and off for about a week now. It comes on while I am driving and stays on but if I turn the car off and back on, it goes off but comes on again while I am driving. The ABS system has even activated a few times when I was stopping on dry pavement. I took it to a shop down the street and he put his ABS scanner on it and no codes were found. So he used another scanner and no codes showed up even though the light was on.
I replaced both front wheel bearings about 2 months ago and they came with new speed sensors.
Any ideas??

Check the connectors to the wheel sensors. It sounds like one is losing contact and triggering the light especially given the fact that you said it resets but comes on after driving.

I agree with GTP Dad,
You might also check the wiring to the connectors.

What year Bravada are we discussing?