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Parts for Whirlpool GEW9868KL0 Dryer - AppliancePartsPros.com

See the attachment for the tech sheet.

First I would check the power.
Use the 750 volt AC scale.
The heater requires the full 240 volts.
Try flipping the breaker off/on slowly a couple times. Sometimes you can loose half the line without actually tripping the breaker.
Check the voltage at the wall receptacle
L1 to L2 should be 240 volts
L1 to Neutral and L2 to Neutral, both should be 120 volts.
If OK
Unplug the unit and check the wires at the terminal strip in the machine to make sure none are loose or burned out
If OK
Check the power at the terminal strip.
Do this with the heater off and on.
[COLOR="Red"]Be careful as 240 volts is lethal !!![/COLOR]

Unplug the unit.
Using the lowest scale on the meter (usually 200 ohms) measure from the red wire on the thermal cutoff to the red wire on the heater.
Should be in the 8 to 12 ohms range.

Check the thermistor. It should be about 10,000 ohms. Use the 20 K scale (20,000 ohms)

If both are OK you will have to do a live test.
Be very very careful.
If you are uncomfortable doing this get a friend who has electrical experience or a pro in.

Unplug the red wire from the heater.
Make sure that it cannot short to anything else while you do your test.
Plug the unit in and start a heating cycle.
You should see 120 volts between the heater connector and Neutral/ground/heater case.
If not then the control board is probably bad.

If OK.
Measure from the red wire you disconnected to the heater case.
You shoul also see 120 volts here.
If not there is a problem with the centrifugal switch on the motor.
Unplug the unit and check the wires at the switch.
It is not that uncommon for one of them to come loose.
Also check that the motor is clean.
If all OK then the motor is probably the culprit.

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.
4. When you start always short the meter leads together. This will tell you that the meter is working and if there is any 0 offset.

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