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Replacement parts for General Electric DWXR473ET3WW Electric dryer | AppliancePartsPros.comGE likes to keep their tech data a secret so I cannot find a wiring diagram specific to your unit.
The following though is probably close.
http://www.applianceaid.com/image/geediagram.JPGOften the wiring diagram is either pasted to the back or in the control console.
The way it works is that when the heating coil is shut off by a thermostat the timer gets it's power through the coil. This is 240 volts so the resistor drops the voltage down to 120 volts which is required by the timer motor.
Unplug the unit
Check the resistor (Item 80 in Section 1), should be around 4000 ohms.
If OK
Remove the wires from the heating coils.
Mark them so you know where they go.
Check each coil for resistance, usually 15 to 20 ohms.
Then check them to the machine's frame/case.
All should be infinite ohms.
If not you have a grounded element, it has broken or sagged and is touching the case and is on all the time. The thermostat's cannot control it and since it does not shut off the timer never advances.
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.