2004 Pontiac Aztek Tailgate Lock Cylinder Replacement Cost

A tailgate lock cylinder is usually located in the tailgate latch handle assembly. It is used to lock or unlock the tailgate on a truck manually with a key. It may also be integrated into the vehicle's central locking system. Often the lock cylinder will have a sensor attached as part of the Anti Theft system to read the key, ensuring it is being unlocked by the proper key.

The tailgate lock cylinder is "coded" to the vehicle's key and it turns when the key is inserted and rotated, just like any other lock. But inside the tailgate, the lock cylinder moves a lever to enable or disable the latch handle. When the tailgate is locked, the handle is disconnected from the latch linkage. When it is unlocked, the latch handle engages the linkage and allows the tailgate to be opened. On some trucks, the lock cylinder also actuates the rest of the locks in the central locking system through the Body Control Module.

Most often, the symptom of a faulty tailgate lock cylinder is that the key will not turn or will not even insert into the hole at all. Sometimes the key gets stuck in one position or another, or it is difficult to remove. Occasionally a key is broken off inside the lock cylinder and cannot be removed. Electrical problems with the locking system are likely caused by the failure of other components.

A bad tailgate lock cylinder is less of a concern for driving and more of an inconvenience, especially if the tailgate is locked shut. A truck can still be driven with a bad lock cylinder. How soon the problem should be corrected is more of a personal concern and need for a tailgate lock. However, if the tailgate lock is connected to the central locking system - if it is activated with a remote key fob - symptoms of a bad lock cylinder could be related to other components, such as a faulty actuator or latch. Because components in the locking system are interrelated, a problem with one lock could affect the other locks.

The lock cylinders on a vehicle are designed to last the lifetime of the vehicle. But, because today's vehicles are more often locked and unlocked with a remote key fob, with the lock buttons on the door panel, or automatically when shifting into gear, the lock cylinder gets little to no use. This state of disuse often causes a lock cylinder to seize up. The tiny tumblers inside the cylinder can no longer move freely and respond to the key. Most complaints about faulty lock cylinders are caused by this situation.

To diagnose a bad tailgate lock cylinder, a technician will attempt to insert and turn the key. If the key is difficult to insert or does not turn freely, the technician may try to lubricate the cylinder and get it to free up. If this is not possible, the technician will remove the latch handle assembly from the tailgate to access the cylinder, the inside of the latch, and the connecting linkage. The goal is to rule out any other components as the cause of the problem. The lock cylinder may be removed from the latch handle assembly to observe how it operates on its own. If the rest of the system is operating properly, the lock cylinder is replaced.

To replace a tailgate lock cylinder, a technician will need to remove the latch handle assembly that houses the cylinder. This may require removal of any panels or closures on the inside of the tailgate, which can present a challenge if an aftermarket protective lining has been applied to the truck bed and tailgate. The lock cylinder is removed from the handle assembly. A new lock cylinder needs to be "coded" by the dealer to fit the key before it is installed.

On today's cars, trucks, and SUVs, it is easy to neglect the lock cylinders on a vehicle, especially the one in the tailgate. But, should the battery die for some reason, a key is the only way to unlock the vehicle. RepairPal recommends that the lock cylinders, whether in the tailgate or in the doors, be operated with the key periodically as part of routine vehicle maintenance. This will help to prevent the cylinders from seizing up and failing prematurely.

Many truck owners have a sprayed-on coating, or bed liner, applied to protect the paint finish from abrasion. This coating also covers the inside of the tailgate. On some vehicles, gaining access to the inside of the tailgate or to the mounting hardware for the latch handle is more difficult because of the bed liner. It may be necessary to cut through the coating to remove hardware or closure panels. In these cases, the bedliner will need to be resprayed over the bolts to maintain the original appearance.

Replacement of the tailgate lock cylinder can usually be performed by someone with an intermediate level of DIY experience. It will be necessary to have the new lock cylinder "coded" to the key for the vehicle by the dealer or a qualified locksmith.