Use a meter to do the following

Check to see that 120v is coming to each side of the connection block.

Check continuity of the thermal fuse. It is likely the problem.

Check continuity of the thermostats

Check resistance of the heating element. Should be 10 to 20 ohms. Make sure it is not grounded or broken.

That should do it. While you are at clean out the venting in the lint filter chute and blower, and the vent to the outside. Obstructed vent is likely the cause of your problem.