First, turn off the switch. The blades may be jammed, but don’t put your hand inside. Your garbage disposal should have come with an Allen wrench (though any will do if it’s the right size). Insert it into the hex-shaped hole in the bottom center of the unit and turn it back and forth to manually free the jammed flywheel.

Once the jam is clear, check to see if you tripped the reset button (usually on the bottom of the unit). If it still won’t turn on or makes a humming noise, call a licensed plumber to avoid damaging the motor or electrical system.