Problem:Ice buildup in freezer and fridge stays warm. After researching the forum, I replaced the thermostat timer & problem returned. So I broke out my multimeter to check the other 2 likely items for this problem. Defrost thermostat reads infinity ohms (at room temp). I believe this is a good reading. Defrost heater reads 27 ohms at room temp. I believe this to be a good reading too. Evap. fan runs as usual. Any ideas on what else could it be? Maybe the new thermostat timer is defective? A longshot I guess. How do I test it? Thanks

Thanks Richappy, I'll give it a try. I checked the defrost thermostat at freezing & it was at 0 ohms. I don't understand that it seems like all the readings are good.