Kenmore 90 Plus Series Model: 68942890

Does your dryer have power? If yes, then check (1) the flow of air outside the house from your dryer tube and (2) your circuit breaker panel for each circuit in the house (I've not seen fuses/breakers built into dryers -- though that could change). Then check (3) your heating element, (4) thermostat, (5) high-temp thermal cutoff switch, and (6) for debris in the air flow path to / from from the centrifugal fan.
Here are 3 resources that helped me with my Kenmore Series 90 Dryer:
No Heat? - http://chris-doityourselfrepair.blogspot.com/2011/10/kenmore-90-series-model-110-clothes.html
Looking Inside My Dryer - http://chris-doityourselfrepair.blogspot.com/search/label/Disassembling%20Kenmore%20Dryer%2090%20Series
Exterior Exhaust Duct - http://chris-doityourselfrepair.blogspot.com/2013/08/cleaning-out-and-replacing-exhaust-duct.html

equation: wattage = amperage * voltage

Read more : http://www.ehow.com/info_8598612_wattage-clothes-dryer.html Hope this helps.

Since no model number was given, check to see if you have a setting commonly noted as "wrinkle guard", "wrinkle shield", "press care" or something to that affect. Those settings will run the dryer for as much as 90 min after a completed drying cycle to prevent wrinkles in clothing, allowing you time to remove the cloths after a dry cycle if you are busy. Pleazer Appliance...

It could be several other things thermal fuse, thermal cut out, hi limit thermostat, dryer coils, heat sensor,or igniter. All of these parts are inexpensive and easy to test and replace.There is a video at t http://appliancehelponline.com/gdryertroublevideo.html his will walk you thru the troubleshooting of these components. It may be a different model but the troubleshooting will be the same.You can also enter your model # for diagrams and illustrations. All parts come with installation instructions. Not all models are available. If you need help disassembling your machine there are videos of this also for most styles.

check your lid switch...bad lid swich...

Sounds like the belt has broken. You could probably also use new drum support rollers. Check out this site which shows how to change a dryer belt:

http://repair2000.com/wpoolbelt.htm

It's not a difficult job if you're comfortable working with hand tools.

Check the automatic door shut off switch and wiring. When the door closes it actuates a switch (completes and electrical circuit) which allows the dryer to operate.

If this is a gas dryer, the rattling noise you hear is usually an indication of the gas valve coils failing on the burner assembly. Your dryer will normally have two of them. One is the main coil, and the other is a pilot position coil. It is recommended that you replace both of them at the same time (usually sold as a set). Searspartsdirect.com carries your parts. Just type in your model number and look under the "Burner Assembly" heading. For comparative shopping, repairclinic.com may also carry your parts. Sometimes at a cheaper price. If this is not a gas dryer, please post back with your model number, so I can assist you better. I hope this helps answer you questions.

Your thermostat could have problem and it confused the temporature inside the dryer. You should change the thermostat. To make sure you can use VOM (vol-amp-milimeter) device to check it. If it reads 0, it means OK. If it reads another number, it is faulty and need changing a new one.
Good Luck

dryer will not start