If the motor will run, but the dryer is not heating you will need to check the heat circuit from the timer to the element. I have included a wiring diagram that shows all of those components (see image below). If you have a volt/ohm meter and are comfortable working around live electricity I can give you a few checks that will help you diagnose the problem.
Disconnect electrical service to the dryer
. Begin by checking each of the thermostats, and thermal cutoff for continuity. Then you will need to ohm the heating element. To do this, you will need to disconnect at least one of the wires to each component and place one meter lead on one of the connectors of that component and the other lead on the other connector of that component. For the thermostats, and thermal cutoff, set your meter to continuity. You should get a tone or â€œclâ€, if you do not hear a tone or if you get â€œolâ€ that component is bad and will need to be replaced. Now to check the heating element, set your meter to ohms and repeat the above process. The heater should ohm approximately 8 to 12 ohms. If not the heating element is bad and will need to be replaced. If all of these components check OK, you will then need to check VAC (Voltage Alternating Current).
Remember to reattach the wires to the components you just finished testing
. Disconnect the red/white wire from the heater.
Re-establish power to the dryer
and start a timed dry cycle. Check the red/white wire to cabinet ground. It should be 120VAC, if not check the red wire at the timer to cabinet ground. If you do not have power at the timer, the timer is bad. If you have 120 all the way to the heater the heater is bad and will need to be replaced. Note: The heating element can be bad even if it ohms correctly.
At this point you should have found the issue. If you require further assistance please resubmit question with details of the checks you have made. I will be looking forward to helping you again in the near future.