You will need an electric testing meter, or at least a friend with one.

Check to see that 120 volts is getting to each side of the connection block. Then unplug the machine and test continuity of the cycling thermostat, high limit thermostat and thermal cutoff. Then check continuity of the heating element. When you find something without continuity that is your problem. If one thermostat is bad I strongly suggest you replace all three.