Not working like it dead - Kenmore Freezer 20.3 cu. ft. Frost Free Upright Freezer

Go to sears.com and use the parts link and enter your complete model number. it will take you to the specs. and diagram.
this problem could be one of several so i am going to list the possibilities:
freezer is stuck in defrost mode (the timer will do that so it could be the timer)
thermostat not working

as far as this these two parts control operation
i would start 1st with the t'sat. unplug then get to the t'sat take off the 2 wires and jump out those 2 wires (put the 2 wire together somehow but be careful)
make sure the wires dont touch anything (especially you when you plug in)
if the freezer kicks on replace t'stat
if it doesnt them replace timer

hope this was helpful