If your refrigerator is not running at all, you hear no fans running and there is no cooling happening in the fridge or freezer, you may have a faulty defrost timer. We show you how to check the defrost timer by using a screwdriver to manually override the switch. If you can do this, then you need to replace the timer. You can find these on Amazon. We also show you how to test the cold control, which is basically a thermostat that you can check with a multi-meter.