It's usually a sensor. Check all the wiring to the sensors to make sure they are secure and not damaged. If that doesn't work you'll have to get it scanned by a tech II(dhp or hptuner can't read BCM codes) to find out which sensor is the culprit. The bad part is you have to replace the hub to replace the sensor. Similar thing happened to me. I replaced the hub and the light didn't go off. Turned out one of the connectors on the abs wires needed replaced.