Well, the GE engineers must have worked overtime on developing this model, taking a rather simple concept like a washing machine and maximizing the complexity of it, for no real discernible benefit.

There is some pretty good diagnostic testing associated with it, so here is the service manual that will take you through the process. The Central Control board is an obvious candidate, but this machine has a complex inverter that also causes problems.

http://appliancejunk.com/ge/washer/31-9135.pdf