I have a GE side by side refrigerator, model GSL85JFPHBS. It sstopped working altogether last month. first the refrigerator stopped working, two day later the freezer part stopped working. I had someone come out and look at it. He cleaned the back part of the unit, and it worked GREAT for 2 weeks. Now the bottom part of the refrigerator is working and is cold, the top part is warm. I checked to make sure the coils were still clean. Any ideas?

I think you meant you have a GSL25JFPHBS (not 85).
It sounds like you have a defrost problem. If your refrig. was off for some time, like a day or more, or it was manually defrosted, it would work for about 2 weeks before the problem would re-occuer. This is caused by a build up of frost on the cooling coils, preventing air flow over them. Un-load the freezer and remove shelves and the back wall inside the freezer. Melt the frost with a hair blower, and replace the defrost heater (part # WR51X10055) and for good measure, replace the defrost thermistor (part # WR55X10025) located at the top of the cooling coils.