how can i fix my deforst timer in my side by side ge refrig erator?

I am not a repair tech, however I manage a service company. I believe the model you have has no defrost timer, but defroster timing is in the electronic control board. I have the same refrigerator. My unit is not defrosting properly. I am replacing the defrost sensor and defrost heater. One parts place mentioned the timer, but most do not. My techs say there is not a timer on this model.

Jim
September 2005