ABS Light

I recently changed the abs module on my 99 silverado because of a problem where the Booster pump was running constatntly whiile the truck was off. this fixed the pump from running all the time but the abs light is still on. I have bled the breaks thoroughly and nothing. the last thing i will do is check the wheel sensors to see if they are opearting correctly. Also, i can drive under 5 miles per hour and the abs light never comes on. once i hit 5 mph the lights turn on. Any ideas?