The top pins and bottom pins line up along the shear line when a key is inserted allowing the lock cylinder to spin freely.
How to change door lock cylinder without key.
Insert another flathead screwdriver under the edges of the tabs holding the lock cylinder in place within the housing.
Open the door and look for the latch plate along the door s edge.
How to remove a door lock without a key.
Look for a small set screw at the base of the handle.
Prop open the door as you change the lock.
Remove this screw using a drill or screwdriver.
Insert a flatheaded screwdriver into the spindle housing hole.
When the key is aligned and removed the pin springs push the top and bottom pins down locking the cylinder in place.
Unscrew this plate and remove the latch from the door if possible.