In order to test to see if the thermostat is closed will require testing it for continuity with an ohm meter. The first thing to check and confirm is the voltage supply where it connects to the back of the dryer. The voltage supply must measure 220-240 volts when testing across the two outside terminals of the terminal block.
NOTE: If you do not have experience in checking voltages and you do not feel safe and confident in doing so, I recommend calling a service technician to diagnose and repair your dryer
The heating element requires two separate lines of voltage in order for it to heat. See images below. The dryer element needs 220-240 volts when measured across the two terminals of the heating element. One leg (L1) of voltage is supplied when the timer contact switch 2 is closed and is routed through the operating thermostat (key#42), thermal cut-off (key#47), high limit (key#48) and over to one terminal of the heating element. The other leg (L2) of voltage is supplied from the terminal block, through the motor switch when (2M and 1M) closes once the motor starts to complete the voltage path to the other terminal on the heating element. In order to diagnose the failure will require testing the operating thermostat, thermal cut-off and high limit with the ohm meter for continuity. Be sure to remove the wires from the component being tested before checking the continuity of the component.
NOTE: Be sure to disconnect the power cord from the power source before removing the lower access panel and checking the components