1999 alero trac light kept coming on?

first, check behind each of the tires to make sure the ABS wire is connected to the hub assembly (a wire comes from the engine and plugs into a clip on the hub). if that doesnt work see a mechanic. is the "anti-lock" light on as well? i have this problem. one of my ABS wires lost the clip so i need to get one from the junk yard. Is the car sputtering? it can also be problem with engine. Mine would come on when I had a problem with my injector.