GE Side by Side Runs but stopped Cooling

[EVESTAR]

Hello

I have a GE Side by Side refrigerator that is about 3 yrs old. It runs but it wont cool. Ice builds up on the back of the freezer but the freezer is more like a frigerator. But the refrigerator is very warm. Even when turned all the way up. I have tried unplugging it and replugging it back up after a couple of hours but yet nothin. It does have a motherboard some one said that it might be that. But I don't see how its not that old. Then I thought it maybe the thermostat. But I couldn't find it. Does anyone have an ideal of what this could be?
Thank you for any advice that will help.

[platinumfreeze]

Chances are it has a PCB, it would be in the rear behind a 5x8 cover plate. The most common defrost problems I see with GE is the glass tube heaters fail. Even if you unplug it for a couple of hours thats not long enough to defrost the ice behind the evap cover in the freezer. Let it defrost completely and look behind the cover in the freezer most of the time the heaters will be black instead of clear glass.

The model # would help alot.

[EVESTAR]

The model number is
GSS20IEPHWW

THANKS

[EVESTAR]

Thanks for the reply but I believe I find the problem. The drain was clogged. I cleaned it out and it seems to be working again. Thanks again.