A trunk lock actuator is composed of a latching mechanism and a series of levers that open the locking mechanism. On newer vehicles, the term “actuator” sometimes refers only to an electronic triggering mechanism that accomplishes the same function. On older vehicles, the part is only mechanical. The concept is the same for both systems, and this guide will cover both.
Both systems will have a cable that runs to the front of the vehicle to a release mechanism normally found on the floorboard of the driver’s side. On the newer vehicles, there will also be an electrical connector running to the actuator and a small motor mounted to it that will activate the mechanism remotely, via the keyfob.
The steps below will outline how to change the trunk lock actuator on your vehicle in the event that it fails.
Part 1 of 2: Disconnecting the old trunk lock actuator
- Appropriate replacement trunk lock actuator
- Flathead screwdriver
- Needlenose pliers
- Phillips head screwdriver
- Socket wrench
- Trim panel removal tool
Step 1: Access the trunk and locate the trunk lock actuator. Chances are if you need to replace this part, then one or more of the normal methods of popping the trunk are not functioning. If your vehicle was produced in 2002 or later, you can always manually open the trunk with the emergency release lever.
If the key and the manual release on the driver’s side floorboard both fail to open the trunk, and your vehicle was produced prior to 2002, you are going to have to use a flashlight and perform the next step from inside the trunk or cargo area. You will need to fold down the back seats and physically access the area.
Step 2: Remove the plastic cover and the trunk liner. The plastic cover on the trunk lock actuator will pop off with a slight amount of prying along the edge. This can usually be done by hand, but if you are having trouble, use a flathead screwdriver or a trim panel removal tool.
The trunk door carpeting may need to be removed as well, if your vehicle has any. Pop out the plastic retainer clips with the trim panel removal tool and set the carpeting aside.
Step 3: Remove the actuator cables and any electrical connectors. The cables will slide out of a locating bracket or guide, and the ball end of the cable will push aside and out of its seat to free the cable from the actuator assembly.
If there is an electrical connector, squeeze the tab on its side and firmly pull straight away from the actuator to remove it.
- Tip: If you are unable to reach the cable with your fingers due to the design of your specific trunk lock actuator, use needlenose pliers or a flathead screwdriver to free the ball end of the cable from its seat.
On vehicles with remote trunk actuators, you will notice both manual and electronic actuating systems incorporated together.
If you have a trunk that will not open and are accessing the trunk from the back seat, manually trigger the mechanism with a screwdriver or needlenose pliers. If you have one, use the emergency release mechanism to get the trunk open. At this point, you will remove the covers, cables, and any electrical connectors as in Steps 2 and 3.
Step 4: Remove the old actuator. Use a socket wrench or phillips head screwdriver to remove the bolts holding the actuator to the vehicle.
If you have an electronic remote actuator on your vehicle, you may not have been able to access the electrical connector that runs to the actuator motor. If this was the case, after you have removed the bolts securing the actuator to the trunk door, remove the electronic connector while removing the actuator from the vehicle.
Part 2 of 2: Connecting the new trunk lock actuator
Step 1: Mount the new trunk lock actuator. Starting with the electrical connector if your actuator is equipped with one, begin reconnecting the trunk lock actuator. Slide the connector over the tab on the actuator and gently push until it clicks into place.
Then line the actuator body up to the mounting holes on the vehicle and use a socket wrench to tighten the mounting bolts.
Step 2: Reconnect the trunk lock actuator cables. To reconnect the actuator cables, you will place the ball end of the cable into it’s seat before placing the cable retainer into the guide bracket of the actuator itself. You may need to manually press back on the spring loaded latch to get both the ball end and the retainer into the proper position.
- Note: Some vehicles use a metal rod instead of a cable at the point of connection to the actuator. This type of connection is made with a plastic retaining clip that fits over the tip of the rod. The concept is the same as the cable type, but can sometimes be a little trickier to reconnect due to the lack of flexibility.
Step 3: Reinstall the trunk liner and trunk lock actuator cover. Reinstall the trunk liner by lining up the connectors to the appropriate holes on the trunk door and press firmly on each connector until it snaps into place.
The actuator cover will have similar connectors that line up to holes in the actuator, and it snaps into place in the same manner.
Step 4: Test your work. Before closing the trunk, test the functionality of all the release mechanisms. To do this, use a screwdriver and simulate the closing of the latch mechanism on the actuator. Test each of the triggering mechanisms this way. If all the release cables are working properly, the job is complete.
With just a few tools and a little spare time, you can replace a faulty trunk lock actuator yourself. However, if you would rather have a professional perform the job, you can always contact one of the certified technicians at YourMechanic to come and replace your trunk lock actuator for you. Or, if you just have questions about the repair, feel free to Ask a Mechanic to receive quick, detailed advice about your issue.
This article originally appeared on YourMechanic.com as How to Replace a Trunk Lock Actuator and was authored by Michael France.