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Replacement parts for MAYTAG LDE412 | AppliancePartsPros.com

First switch the breaker off/on slowly a couple times. Sometimes you can loose half the line without actually tripping the breaker. The heater requires 240 volts while the motor only uses 120 so depending which side drops out you can get the symptoms you see. Better yet check it at the plug with a meter for 240 volts.

Next check the heater then the thermostats.
I cannot find a thermal fuse in this unit which seems strange but cannot find a wiring diagram for this machine. Check in the control console for the wiring diagram it will help with trouble shooting.

Be sure to unplug the unit when working on it.

If you do not own a meter, I would suggest you purchase a one. You can get a decent digital multimeter for under $20.00. You do not need fancy though it is nice if the leads are a couple feet long.
If it saves ordering one unnecessary part it has paid for itself and you end up owning a useful tool.
Most places will not let you return electrical parts so if you order it, you own it.
A couple things to watch when measuring ohms and continuity
1. Always remove power from the machine otherwise you could blow your meter.
2. Always disconnect at least one side of any device you are checking. This eliminates the possibility of measuring an alternate/parallel circuit path.
3. When checking for closed contacts and continuity use the lowest scale (Usually 200 ohms). Then try higher scales. This scale is 0 to 200 ohms so if the device you are measuring is 300 ohms this scale would show an open circuit which it is not, you are just measuring outside the scale's dynamic range.

There is a good STICKY at the start of this forum about it's use.

Here is a good site with basic dryer repair help.
http://www.applianceaid.com/dryers.html