[svandy]

My freezer won't defrost automatically. I have to defrost it manually.

[woodchuck]

check defrost timer, defrost heater, defrost thermostat Refrigerator Repair Guide: How To Fix a Refrigerator - ACME HOW TO.com

In most of the new units they now have the evaporative defrost control instead of the timer.. It senses when to defrost based on how many times and for how long the door is opened. It's more energy efficient but there does seem to be lots of problems with the board.