When you have found the problem, you have found the problem. What do we mean by this? Very few times on appliances, especially with electrical problems, is there more than one component defective. If you followed rules one through four, and diagnosed a dryer with a defective heater, then you found the problem. Don’t complicate the issue by trying to make it more than that. Sometimes a heater on a dryer will be defective because of an external issue, or even a stuck thermostat. But most of the time when you have found the problem, you have found the problem. Rarely do you find a situation where you have a heater on a dryer that is defective, and the timer is also defective.
The reason for this is that in order for the heater to become defective, it must have adequate voltage to it. If there was another component causing problems within dryer, chances are it would not get its full 220 volts. If you find a drain solenoid on a dishwasher is stuck because it is burned up, that’s going to be the problem. The chances of anything else being defective on that dishwasher are extremely low. And this goes for almost all electrical problems, on all appliances, any brand, any model. And finally, by going to the component that is supposed to do the work, you are most likely to find the problem. For example, on a dryer where the motor is humming when you push the start button, by going to the motor and inspecting it, you may find that the motor is defective, but you may find that it is simply covered in dust and the motor centrifugal switch is hanging up. By the way, this is why you should never run a dryer without a properly installed vent to the outside.
To prevent serious injury or death, always make sure that the power to the appliance is either turned off, or that the appliance you are working on is unplugged from the electrical supply. Unless otherwise noted, all of the troubleshooting techniques listed are to be performed with the power disconnected from the appliance. When working on washing machines and dish washers, it’s also a good idea to turn the water supply off, just to be safe.
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