During normal operation, the impellers of a garbage disposal push food toward blades on the sides of the canister. The food gets mashed into pulp and drains through a fairly small gap on the edges of the impeller rotor. The gap is so small that bones, plastic and other hard items can get stuck there and prevent the rotor from turning. The garbage disposal has an internal overload protector that trips when this occurs to prevent the motor from burning out. You reset the overload protector by pushing a button, but first you need to clear the clog.
Clearing a Clog and Resetting the Disposal
Some garbage disposals have a reset key that fits into a slot on the underside of the rotor. The purpose of the tool is to enable you to easily clear clogs. If your garbage disposal doesn't come with one of these keys -- which is really just a 1/4-inch Allen wrench -- you'll need a wooden spoon or a broom handle.
Turn off the breaker in the main panel that controls the garbage disposal circuit. This is an important procedure that ensures no one is able to accidentally turn on the disposal while you're working on it.
Insert the reset key into the slot under the disposal rotor and move the rotor back and forth until it begins to turn more freely. If your disposal has no key, insert a wooden spoon or broom handle in through the sink opening and use it to move the rotor.
Look into the disposal with a flashlight and retrieve any items that have worked loose, using a pair of tongs. Don't reach in with your fingers.
Continue moving the rotor and retrieving debris until the rotor spins freely.
Turn on the breaker, then press the reset button until it clicks. This button is located on the bottom of the canister on models that have reset keys. On most other models, its on the side of the canister, near the bottom. It's small and red, so it's easy to find.
Turn on the faucet, then turn on the disposal switch and allow the unit to run for 10 seconds to clear any debris that might still be there.