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Locks: Description and Operation


KEY IDENTIFICATION AND USAGE
The lock cylinder keyway is designed so that other model keys will not enter a current model lock cylinder. A single key is used for all locks on the vehicle.

The key identification is obtained from the four-character key code stamped on the knockout portion of the key head. Knock the plugs out of the key head after code numbers have been recorded. The code list, available to owners of key cutting equipment from equipment suppliers, determines the lock combinations from the code numbers.

CUTTING KEYS
After the code has been determined from the code list or the key code diagram, perform the following steps:
1. Cut a blank key to the proper level of each of the tumbler positions.
2. Inspect the key operation in the lock cylinder.

REPLACEMENT LOCK CYLINDERS
New lock cylinders (except ignition lock cylinders) are available from the service parts warehouse with new lock cylinder locking bars. The tumblers are also available and must be assembled into the cylinder as recommended.

LOCK CYLINDER TUMBLER OPERATION
All lock tumblers are shaped alike with the exception of the notched position on one side. As the key is inserted into the lock cylinder, the tumblers are lowered to the correct height so that notches on each tumbler are at the same level. When the notches on all 6 tumblers line up, 2 small springs push the side bar into the notches, allowing the cylinder to turn in the cylinder bore. Five types of tumblers are used in making the lock combinations, and each is coded and stamped with a number between 1 and 5.