2011 LOnestAR ABS light oneHere is

Sounds like an interesting issue. There really isn't much you can do without getting a laptop connected and seeing what is going on. The a/c is computer controlled. Couple of theory's, engine may be losing communication partially with the rest of the truck, causing the abs light and ignoring the fan request from body controller for the a/c. Once the body controller sees a/c pressure too high it won't allow the a/c to work until the next key cycle. A/C system is all controlled by the body controller, body controller can also turn on the abs light in the cluster even though there is no actual abs fault. These systems are sensitive to bad grounds, you can clean all your cab and battery grounds and see if the problem goes away.