[jem1972]

I discovered my fridge was getting warmer and warmer. The freezer was as cold as it should be. Figuring the cold air vent down to the fridge was possibly blocked with ice, I removed the back of the inside of the freezer and let it thaw. This seemed to fix the problem. Then my fridge started getting warm again a few days later. When the problem first occurred, I had the temps for both the fridge and freezer on the coldest settings, and the outdoor temp was in the 90's. Last night I adjusted the freezer temp so it was a little warmer, hoping this would make the fridge colder, but that didn't work. I'm not sure if the outdoor temp had anything to do with it, but the outdoor temp dropped down to the 70's after the first "fix".

[PS Volunteer - Appguy]

Remove back panel of freezer and check frost pattern. If all frosted over, partial defrost coils and locate defrost thermostat, a little round thing clipped to evaporator.
While still cold, check it's resistance, should be near zero. If not, replace. If ok check resistance of defrost heater, if ok, you have a bad defrost timer.