Toshiba Defrost System Failure

Freezer runs continuously and forms heavy frost on the evaporator cover and food packages.

Advertisements

Safety Warning

This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.

If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.

Advertisements

Possible Causes

Open defrost heater, Failed defrost thermostat or thermal fuse, Defective defrost sensor, Main control PCB not initiating defrost

How to Fix / Troubleshooting

Safety: Unplug the freezer before accessing the evaporator and heater. Beware of sharp fins and ice.

Steps:

  • 1. Manually defrost: Empty the freezer as needed and allow ice to melt, or use warm water and towels. Do not chip ice with sharp tools.
  • 2. Access components: Remove the inner rear panel to expose the evaporator, defrost heater, and defrost thermostat/thermal fuse.
  • 3. Test heater and thermostat: With wires disconnected, measure continuity of the heater and thermostat. Replace any open components with Toshiba-specified parts.
  • 4. Check defrost sensor: Test the defrost thermistor resistance and replace if out of range.
  • 5. Control board: If all hardware is good, the main control PCB may not be sending power to the heater and should be replaced.
Advertisements

Repair Difficulty

Hard 4/5

Required Part

Defrost Heater Assembly
Check Price on Amazon

We may earn a commission from links on this page.

Advertisements