Product review (5 stars): Easy Fix for Failed Defrost!
A very inexpensive repair that was very easy to complete!  Fifteen minutes worth of work and the defroster is working again.  Fortunately we were able to test the heating element (much more expensive) for continuity with a multimeter and were able to rule it out as the failed part.  After pulling out the old thermostat and testing it for continuity, it had indeed failed.