My fridge doesn't auto defrost anymore - I've had this problem for months. The freezer coils get frosted over and I have to manually defrost (by unplugging for 24 hrs) every 3 or 4 weeks. I first replaced the bi-metal thermostat sensor - still no auto defrost. I then got a multimeter and tested...
I have a Kenmore 106.57034601 and I did test 2 and I heard it click twice but the clicks sounded different so how would I check for open thermostatThe entire defrost system consists of three parts, the defrost heater, the defrost thermostat, and the defrost control board.
If the defrost thermostat and the heater are good, the defrost control board is bad.
To get into defrost test mode try option #1 first. If that doesn't work try option #2
Unplug the refrigerator for a minimum of 30 seconds
Turn the cold control to the off position, then restore power.
Turn the cold control OFF for 15 seconds, ON for 5 seconds, OFF for 15 seconds, ON for 5 seconds, OFF for 15 seconds, ON for 5 seconds, Turn the control OFF.
In 3-8 seconds the control will turn on the defrost heater for 21 minutes or until the defrost thermostat opens
To terminate the test early remove power from the machine.
When the machine enters test mode, listen to the relays on the defrost control board. If the relay clicks once, check for an open heater. If the relay clicks twice, check for an open defrost thermostat.
Last edited by a moderator: