July 20, 2015

How to replace a refrigerator defrost control assembly

By Lyle Weischwill
How to replace a refrigerator defrost control assembly

This DIY repair guide shows how to replace the defrost control assembly in some LG and Kenmore refrigerators. The defrost control assembly, located next to the evaporator in the back of the freezer, monitors the evaporator's temperature to protect it from overheating. It includes a defrost temperature sensor, a fuse and a wire harness. If the defrost temperature sensor isn't working correctly, the evaporator overheats during the defrost cycle, which in turn blows the fuse. Less commonly, a shorted defrost heater or faulty wiring could blow the fuse. In both cases, the freezer won't defrost and the electronic display panel shows an error code. Replace the defrost assembly with a manufacturer-approved replacement part if the defrost sensor fails or the fuse blows.

This repair procedure works for LG and Kenmore 795-series French door refrigerators. The procedure for accessing defrost components in the bottom freezer compartment is basically the same for many Whirlpool, Maytag, Amana, Samsung, Frigidaire, Electrolux and GE refrigerators.

Quick links
Tools required
Phillips screwdriver
Slot screwdriver
Pliers
Work gloves
Repair difficulty
Time required
120 minutes or less
Repair difficulty
Time required
120 minutes or less

Instructions

  1. 01.

    Disconnect the electrical power and empty the freezer

    Safely store any food that could deteriorate while the refrigerator is shut off. Then unplug the refrigerator or shut off the circuit breaker for the refrigerator.

    Remove the shelves and baskets from the freezer compartment.

    Tip: Refer to your owner's manual for guidance on how to remove the baskets and shelves from the freezer.
    Empty the freezer.

    Empty the freezer.

  2. 02.

    Remove the ice maker

    If your model has an ice maker in the bottom freezer, unplug the wire harness, remove the mounting screws and pull the ice maker assembly out of the freezer.

  3. 03.

    Remove the freezer drawer and side rail assemblies

    If you have a drawer freezer, remove the screws on the outside of the guide rails and pull the door up and out. 

    Remove the screws that secure the side rails to the freezer walls and lift the rail assemblies out of the freezer.

    Remove the side rails.

    Remove the side rails.

  4. 04.

    Remove the back panel

    Remove the mounting screws that secure the inside back panel of the freezer compartment.

    Before removing the back panel on some models, you must first open the access panel on the top left side and unplug the wire harness for the evaporator fan assembly. You might also have to release the cover of the temperature sensor on the right side and release the sensor from the cover before pulling the cover out.

    Pull the bottom of the panel out slightly to release it and then remove the panel from the freezer compartment.

    Remove the back panel.

    Remove the back panel.

  5. 05.

    Remove the defrost control assembly

    Unplug the wire harness from the defrost control assembly. Use pliers to release the defrost control assembly from the cable ties and pull it out of the freezer.

  6. 06.

    Install the new defrost control assembly

    Insert the new defrost control assembly and secure it with the cable ties. Plug in the wire harness.

  7. 07.

    Reassemble the freezer

    Work the panel back into place at the back of the freezer compartment and reinstall the mounting screws.

    Reinstall the freezer door and side rail assemblies.

    Plug the ice maker into the wire harness and reattach the ice maker to the side wall.

    Reinstall the baskets and shelves in the freezer compartment.

    Reinstall the back panel.

    Reinstall the back panel.

    Reinstall the freezer shelf.

    Reinstall the freezer shelf.

  8. 08.

    Restore electrical power

    Plug in the refrigerator or turn on the house circuit breaker to restore power.

Warning: Undertaking repairs to appliances can be hazardous. Use the proper tools and safety equipment noted in the guide and follow all instructions. Do not proceed until you are confident that you understand all of the steps and are capable of completing the repair. Some repairs should only be performed by a qualified technician.

Symptoms common to all refrigerators

Choose a symptom to see related refrigerator repairs.

Main causes: leaky door gasket, defrost system failure, evaporator fan not running, dirty condenser coils, condenser fan not running
Main causes: blocked air vents, compressor problems, condenser or evaporator fan not working, control system failure, sensor problems
Main causes: jammed ice cubes, broken ice maker assembly, dirty water filter, kinked water line, bad water valve, freezer not cold enough
Main causes: water valve leaking, frozen or broken defrost drain tube, overflowing drain pan, cracked water system tubing, leaking door seal
Things to do: clean condenser coils, replace the water filter, clean the interior, adjust doors to prevent air leaks, clean the drain pan
Main causes: damaged door seal, faulty defrost sensor or bi-metal thermostat, broken defrost heater, bad defrost timer or control board
Main causes: control board or cold control failure, broken compressor start relay, compressor motor failure, defrost timer problems
Main causes: blocked vents, defrost system problems, evaporator fan failure, dirty condenser coils, bad sensors, condenser fan not working

Repair guides common to all refrigerators

These step-by-step repair guides will help you safely fix what’s broken on your refrigerator.

How to replace a refrigerator temperature control board

If the temperature in your refrigerator doesn't match the temperature you set, the problem could be the temperature control board—a service technician can give you a definite diagnosis. If the board is at fault, follow these steps to replace it yourself.

Repair difficulty
Time required
 30 minutes or less
July 20, 2015
By Lyle Weischwill
How to clean refrigerator condenser coils

Help your refrigerator run more efficiently by cleaning the condenser coils. It's easy and takes just a few minutes.

Repair difficulty
Time required
 15 minutes or less
July 20, 2015
By Lyle Weischwill
How to replace a refrigerator water valve

Replace the water valve that feeds water to the ice maker and water dispenser if it no longer controls the flow of water.

Repair difficulty
Time required
 30 minutes or less

Articles and videos common to all refrigerators

Use the advice and tips in these articles and videos to get the most out of your refrigerator.

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