My Whirlpool Dry Model GGQ9858JQ1 turns off in heat mode after a few minutes

Check all heating components. If they all check out good, then most likely a control problem

Hello David. We regret to hear about your Dryer not working on select cycles. We recommend disconnecting power from the breaker for at least a minute and then turning the breaker back on to do a master reset on the Dryer. If that does not help then we can only recommend service. If you would like for us to schedule service for you, can you please email us your address, phone number, the model and serial number, the website you were contacted on, Fixya, your review ID, and date of purchase to Whirlpool_Digital@whirlpool.com.

Try using timed dry insted of sensor dry if runs ok you need aew sensor strips. also make sure dryer vent is clean.

it is over heating you might have unplugged a wire to the thermostat when you had it apart or the thermostat has went out.

This caused by one of two possible things. Either you have poor air flow, or a clogged vent preventing air from flowing freely and therefor making the dryer short cycle, which in turn will take you two or three times to dry yor clothes, or the heating element has gone bad, burnt in half and is making contact with the case to provide it just enough power to barely heat. The second thing is a very rare occurance. I would turn the dryer on, find out where the air vents out to, and with the dryer running, go to where it vents and check to see if there is a strong flow of air. 9 times out of 10 that is going to be your problem. Another way to check air flow is to just pull the vent off the back and let the dryer run and see if your clothes dry faster. If you do it that way and they still take a long time to dry, then you'll probably need to replace the heating element

This caused by one of two possible things. Either you have poor air flow, or a clogged vent preventing air from flowing freely and therefor making the dryer short cycle, which in turn will take you two or three times to dry yor clothes, or the heating element has gone bad, burnt in half and is making contact with the case to provide it just enough power to barely heat. The second thing is a very rare occurance. I would turn the dryer on, find out where the air vents out to, and with the dryer running, go to where it vents and check to see if there is a strong flow of air. 9 times out of 10 that is going to be your problem. Another way to check air flow is to just pull the vent off the back and let the dryer run and see if your clothes dry faster. If you do it that way and they still take a long time to dry, then you'll probably need to replace the heating element

Please check the video in the link below if it helps.

http://www.youtube.com/profile?user=DIYAPPLIANCEREPAIR#p/u/2/e6cMej-C1XQ

Thats what it's supposed to do hopefully the clothes are coming out dry. The dryer has both thermal sesors and fuses that tell the dryer when to heat up and when to cool down. So yes the heating element will come on and go off multiple times in a cycle.

first check the circuit breaker in the house, turn it off then back on. if that does not do it then let me know so we can go to the next step. Mike

This can be due to malfunctioning of any of these 4 devices..
1)Heating element
2)Thermal fuse
3)Thermostat
4)Timer motor
For more info and troubleshooting checkout this link..
http://www.partselect.com/dryer+dryer-wont-heat+repair.htm