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Replacement parts for Kenmore 59650399000 | AppliancePartsPros.com

[COLOR="Blue"]Stuck in defrost mode?[/COLOR]
No, since the coils are heavily frosting/icing up you are not getting defrost.
If you were stuck in defrost the symptom would be that the fans and compressor would not come on.


First remove the evaporator cover in the freezer so you can see the coils.
Do not let them de-ice.

If they are heavily frosted up to the point that the fan cannot pull air through them you have a defrost problem.
Manually force a defrost cycle by turning the defrost timer cam till the fans and compressor turn off.
There is usually a hole in the cover to let you do this without taking anything apart. On your unit I think it is behind the front kick plate.
Now check the defrost heater to see if it is on.
Be careful you do not want to burn your fingers.
If the heater is on then the timer needs replacing, re: it is probably stalling during it's rotation so is never getting into a defrost cycle.

If not on.
Unplug the unit.
Remove the wire for one side of the heating element from the wiring and measure it for continuity, usually around 20 ohms or so.

If the heater is OK
Remove one wire to the defrost thermostat and measure it, should be 0 ohms when frozen. Note that it opens just above freezing so must be frozen to check it. Also inspect it, if it is bulged at all replace it even if it measures OK.

If both the above are OK then odds are the defrost timer contacts are toast.
Best way to test this is a live test to see if you have 120 volts across the heater/defrost thermostat combo.