Slide the patio door all the way open.
How to change locks on a sliding glass door.
This indicates there is no glass.
Take your graphite pen and insert it into the lowermost screw hole quickly to prevent the latch from falling into the frame.
Unscrew and remove the existing lock.
Screw hole size the distance between the centers of the mounting screw.
How to install a key lock on a sliding glass door.
Find the name of the manufacturer and model number on the sliding door and use this information to purchase a lock that will fit.
How to replace a lock in a sliding patio door.
End face plate type round or square.
Place your head near the frame and tap it with the end of a screwdriver until you hear the sound change.
Clean the door frame with hot soapy water and allow it to dry completely.
First remove the screws securing the door handle in place first with your phillips screwdriver and slide the outer latch lever out of place.
Width of the lock.