I left rfg door ajar all night, woke up to warm rfg and frzr coils covered with snow. Melted the snow off coils with dryer. put all back together. now frig and freezer are both cooling just fine. But I kept the frzr panel off to check the frost and sure enough it is covered with substantial frost after about 20 hrs. Have read about checking the defrost timer first. But I CAN'T FIND IT anywhere on my model GSS25jsre. Please help me! I don't have a multimeter tester, so was thinking I'd just try to replace all 3 suspected parts: defrost timer, thermostat, and heater. Exactly which parts are the ones I'd need to order for my model? I see several listed for each and don't want to make a timely mistake.

Thank you so much!
Val :)

Thk you! I'll thaw coils, ck heater element and put panel back now. Do you know if my model has a timer that I can switch on manually? Where would it be? I've taken back panels off and don't see one anywhere.
Thx again for your reply!! :-)