Assembling and Coding Rear Compartment Lid Lock

The rear compartment lock cylinder uses 8 of the 10 key cut positions, 3-10. The tumbler orientations alternate in adjacent locations from side to side with four on each side.

Fig 1: Rear Compartment Lid Lock
Courtesy of GENERAL MOTORS CORP.
IMPORTANT: The front side door lock cylinder tumblers (3) are not self-retaining and must be held in place if the key is not fully inserted into the lock cylinder, or until the cylinder (1) is assembled into the case assembly (4).
1. Hold the uncoded cylinder (1) so that the side with the drain hole is facing downward.
2. Insert 1 tumbler spring (2) into each of the tumbler spring holes.
3. The first tumbler to be loaded will be the key cut position #3, the third number in the key code. Determine the cut depth at this position and insert the corresponding tumbler (3) in the slot nearest the front of the cylinder (1). This is the side where the key would be inserted.
4. In the same manner, determine the cut depth and corresponding tumbler and install the three remaining tumblers (3) into the tumbler slots at key cut positions 5, 7, and 9.
5. Verify the correct loading of the tumblers (3) by holding the tumblers in position and inserting the matching key into the cylinder (1). The tumblers should be flush with the outside diameter of the cylinder.
IMPORTANT: The tumblers (3) are NOT self-retaining and must be held in place.
6. Rotate the cylinder (1) so that the side with the drain hole is facing upward. Remove the matching key.
7. Insert a tumbler spring (2) into each of the 4 tumbler spring holes.
8. The first tumbler to be loaded is key cut position #4. Determine the cut depth at this position and insert the corresponding tumbler (3) in the slot nearest the front of the cylinder (1).
9. In the same manner, determine the cut depth and corresponding tumbler and install the three remaining tumblers (3) into the tumbler slots at key cut positions 6, 8, and 10.
10. Verify the correct loading of the tumblers (3) by holding the tumblers in position and inserting the matching key into the cylinder (1). The tumblers should be flush with the outside diameter of the cylinder.
11. Lightly lubricate the tumbler (3) surfaces using the provided lubrication.
12. With the matching key fully inserted into the coded cylinder install the coded cylinder into the case (4).
13. Remove the matching key. Keep the coded cylinder (1) fully inserted into the case (4).
14. Insert 1 shutter spring (5) into each of the 2 shutter spring holes, located on the front face of the cylinder (1).
15. Install the shutter assembly (6) into the recessed area on the front face of the cylinder (1). Position the ends of the pin on the shutter assembly in the pin cavities located in the front face of the cylinder.
16. Install and stake the lock cylinder cap (8) by rolling the edge of the cap over onto the head of the case (4). Do NOT damage the lock cylinder cap or the case in any way while staking the cap. Stake the cap securely to the case and verify that the shutter springs (5) push the shutter assembly (6) up against the inside surface of the cap.
17. Install the gasket (7) over the end of the cylinder assembly and slide the gasket all the way up the case (4) until the gasket is positioned behind the cap (8).
18. Install the return spring (9) over the back end of the cylinder (1) with the straight hook facing the rear of the case (4). Engage the straight hook of the return spring with the hook feature on the rear of the case.
19. Install the lever (10) onto the end of the cylinder (1).
20. Install the retaining ring (11) in the groove at the end of the cylinder (1) to secure the lever (10) to the cylinder. Engage the bent hook of the return spring (9) with the lever.
21. Install the theft deterrent switch (12) onto the end of the cylinder (1) and snap the switch legs onto the case (4). Engage the theft deterrent switch with the end of the cylinder and attach the switch securely to the case.
22. Verify the operation of the lock assembly. The return spring (9) should provide a counterclockwise snap back.