Kenmore heavy duty 80 series

The buzzer is wired through a switch on your dryer motor. The switch is NOT a normal switch... it's a centrifugal switch meaning that it is mounted on the motor shaft and rotates along with it. When it "spins up" centrifugal force flings it outward to make contact with the terminals on the outer edge of the inner motor housing (This tells the timer that the motor is functioning properly and it can now begin to heat the clothes. This is also the switch that keeps you from having to hold in the "Start" button 'til the clothes are dry) When the timer kills power to the motor, the buzzer sounds off because of this switch. As the motor slows, springs retract the switch from the contacts and shut off the buzzer. Make sense so far? Sounds like your centrifugal switch is getting stuck. Unplug the dryer and gain access to the motor. Then use Contact Cleaner in a spray can to spray and clean every inch (inside and out) of the motor. This should get you going again.