How to Replace a Schlage Key Plug

Open the door and remove the two screws on the inside rose securing the two knobs together, using a Phillips screwdriver. Grab the inside doorknob with one hand and the outside doorknob in your other hand. Pull the knobs away from the door.

Insert your key into the Schlage lock and rotate the cylinder to the right 90 degrees with the key. Insert a small finishing nail into the lever catch hole on the neck of the doorknob near the rose plate. The rose plate is the escutcheon covering the hole in the door for the lock set.

Pull the knob handle with one hand while pressing the finishing nail into the lever catch hole. Once you pull the knob off the stem, turn the key back to the left 90 degrees and pull the key plug. The key slot on the lock cylinder should be pointing down.

Hold the doorknob in one hand with the back of the knob resting on your palm. Push the key cylinder from the front of the knob with your thumb, pushing the cylinder into the palm of your hand.

Pull the c-clip off the back of the cylinder with a pair of needle-nose pliers. The c-clip secures the key plug to the inside of the cylinder. Insert the key into the key cylinder and rotate the key to the right 90 degrees.

Insert a plug follower into the back of the key cylinder. A plug follower is a round dowel that fits inside the key cylinder in place of the key plug. Pull the key slowly to pull the key plug out of the cylinder, while pushing the plug follower through the key cylinder. This prevents the springs and top pins from popping out.

Remove the tape off the top of the new key plug. If you want to keep the same key from the previous plug, dump the pins out of the new plug. Remove the pins one at a time from the old plug and place them into the corresponding hole of the new plug.

Insert the key into the new plug. Insert the end of the plug into the key cylinder, slowly pushing the plug follower out of the key cylinder. Once the new key plug is in the key cylinder, rotate the key 90 degrees to the left. Push the c-clip over the groove on the back of the key cylinder to secure the key plug.

Remove the key from the key plug. Insert the key cylinder through the back of the knob, with the key slot pointing down. Once the key slot is properly positioned in the doorknob, insert the key and rotate the cylinder 90 degrees to the right.

Push the knob back over the stem until you hear the lever catch lock into place. Rotate the key cylinder 90 degrees to the left and remove the key. Insert the doorknobs into the door, and secure with the two retaining screws.