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Replacement parts for 596.57587790 models | AppliancePartsPros.com

My evaporator coils were freezing up, so I started looking into it. The timer appears to be working (it does cycle through on its own). One time I checked and the heating element did turn on, but now it doesn't.
Just because the timer runs does not mean that it's contacts are OK.


Now I've noticed that the fan is not running (inside the freezer). I checked the terminals and I have 0 voltage. Is there possibly a link between the issues? Does the defrost timer by chance turn the fan on / off?
Yes they can be linked. The defrost timer should turn off the evaporator fan, the compressor fan and the compressor when in a defrost cycle.

It sounds like the defrost timer's contacts are intermittent.
You could check the defrost element and the defrost thermostat.
The defrost element should be approximately 20 ohms.
The defrost thermostat should be 0 ohms when frozen. Note it opens (infinite ohms) just above freezing. Sometimes you can actually see that it is toast as it will be bulged.

If both the above are OK then replace the defrost timer.
Be sure to disconnect one side of the device you are measuring this prevents reading an alternate/parallel circuit path.