firstly you have not stated what sort of motor you have which is normally a basic requirement,if your code reader stated which corner was giving problems then would check sensors/wiring and some abs ststems run off wheel bearings which can give problems also,if not a bearing then an exciter ring which can rust up,clog up with dirt,break up,these are some things to check,whatever motor you have may need a more in depth code reader to determine further what corner is giving you problems
cdc
July 2012