You may need to replace your trunk key lock if you have lost your trunk key or the lock has become worn or damaged. You need not purchase an entire lock assembly; you only need a new cylinder that has been machined to match your master car key. A locksmith can read the reference numbers on your old cylinder and find a new one for this purpose. You can replace a trunk key lock in an afternoon if your locksmith has a replacement cylinder in stock.
Open the trunk of your car. If the lock is stuck shut, use a drill with a metal bit to release it. Place the bit into the key slot of the lock and drill through the entire cylinder. Push up and own on the trunk lid until the lock releases and opens the trunk.
Remove any interior body panels that prevent access to the trunk key lock. Use a flat-head screwdriver to pry out any clips or push snaps that hold the body panels in place.
Remove the four bolts that hold the striker plate of the lock to the body of the car. The striker plate is a flat, brass-colored plate to which the latching mechanism is attached. Once the bolts are removed, pull the plate from the lock. You will see that the plate was covering two access holes on either side of the trunk lock.
Insert a Phillips screwdriver through the access holes to remove the four screws holding the trunk lock cylinder in place. Pull the trunk lock out of the car when all the screws are removed.
Release the cylinder pin. On the side of the key lock cylinder (the round tube in the center of your lock that the key turns to activate the lock) there will be a small circular pin that is flush to the surface of the cylinder body. Use a straight metal pick to push the head of the pin into the body of the cylinder. Hold the pin in and push on the key face of the cylinder with your thumb. The cylinder will pop out of the back of the lock.
Note the reference numbers for replacement. On the side of the cylinder will be a series of numbers that the locksmith will need to find the correct replacement for your car. Obtain a replacement cylinder.
Install your replacement cylinder by pushing it into the old lock. The pin on the new cylinder will automatically pop into the locked position to hold the cylinder in place. Reverse the steps above to reinstall the lock.
