Opened up back panel tonight to check on defrost system. Disconnected defrost heater at both ends and checked continuity accross it. Measured 33 ohms. Wiring diagram that came with unit lists normal range of 29 ohms +/- 5%. So this seems to be within range.

Next checked defrost thermostat. It was warmed to room temp by the time I got to it, so it read open, which the wiring diagram lists as normal at room temp. Will need to freeze it somehow to check the continuity again. Any tips on how to do this without a second freezer? It takes me too long to get inside the back panel.

Wanted to check the thermistor as well, but I could not find how to unplug it without cutting wires. Is that the only way to check it?

Thanks for any help!

whitman

Thanks richappy

Last night after posting the follow up I opened the toe kick panel on the bottom of the fridge and found that the condensing coil was packed with cat hair and dust. It was disgusting! So I grabbed my coil brush and vacuum and went at it. I also took of the rear panel and cleaned the coils and fan. Things are much cleaner under there now.

Also while under there, I discovered a trouble shooting guide that was taped to the bottom of the unit. It has instructions on how to do a forced defrost and also various service tests for checking the defrost thermostat circuit, thermistors, condenser fan, evap fan, etc. I let the fridge/freezer cool over night and checked them all this morning and all systems were working fine. (Thermostat was closed)

So now this leaves me a little confused....Could the defrost problems be caused by the clogged condenser coils? Or perhaps the thermostat is opening too soon? I may just order the thermostat since its easy to get at in the back panel and its a cheap part.

I attached the trouble shooting guide and wiring diagram in case anyone comes across this post and is looking for it. my guess is it applies to any recent model kenmore bottom mount refrigerator.

So I have ruled out the thermostat (i think). I performed the forced defrost this weekend to see if the thermostat was working. The fridge had been plugged in for a week now and I could see ice build up on the coils so I know that it has not been defrosting. I started the defrost and it soon started dripping and I could hear the sizzles as the water hit the element. The catch pan under the unit filled pretty good so I believe it was not defrosting all week.

So where do I go from here? It does not look like its the thermostat, and the heater check out ok as well. Perhaps the adaptive defrost on the control board? Like I said in my first post, the repair man replaced the control board and said it was reporting an error. Its possible that it was replaced with a damaged unit i suppose. Unfortunately, its past his 30 day warranty so I may have to get a new one.

Is there a way to test the control board?

Or could the thermostat be opening at too low of a temperature?

Thanks!

Go to the sticky above "GE refrigerator (GS* & PS* models) .... page 3, look for my response to manually force defrost.

There is no way to test the motherboard, GE technicians with special equipment can.