Your temperature thermostat or heater coil is most likely bad, you can test by ohming each. NOTE: The heating circuit should be troubleshot with the dryer UNPLUGGED. Dangerous voltages are still present with the dryer turned off. Resistance readings are as follows:
Heating Element (located inside heater
box) – remove the two leads from the ceramic terminals on the heating element and take a reading across the terminal points. It should read 9 - 13 ohms.
Thermal Cut-Out (TCO) (mounted to the heater box.) - unplug wires and take reading across connector tabs. Reading should be 0 ohms.
Hi-Limit Thermostat (mounted to the heater box, closest to the heating element leads) - unplug wires and take reading across connector tabs. Reading should be 0 ohms.
If any of the above readings are abnormal, replace the component. NOTE: If the TCO or Hi-Limit Thermostat is defective it is highly recommended by most manufacturers to replace BOTH components at the same time. They are often sold as a set. Without doing so, these components can cause potentially fail again.