Tail Light Replacement DIY Guide
DISCLAIMER
As always, follow all safety protocols. Don't undertake this task if you aren't comfortable with it, fully understand it, and are capable of completing it. The information provided may be incomplete or inaccurate. You are ultimately responsible for anything you do. Neither Redpants, LLC or myself is responsible or liable for anything that may occur.
This is an oddly common job on Gaydon-era Aston Martins that people do for a couple of reasons. Aside from replacement due to an accident, people also put in new tail lights to replace ones that have built up condensation within them, and also to change from red tail lights to clear ones (and vice-versa). The is actually pretty easy, but requires some finesse during reassembly. This DIY Guide shows how to do the two tail lights themselves, then continues to the center high mount signal light (CHMSL) which is the third brake light that’s mounted in the trunk lid of many of the cars. If you have the third brake light mounted in the rear window of your car, like the DB9 coupe, then that portion of the DIY Guide doesn’t apply to your car.
Side Note: If your tail light has condensation but still works, you may be able to mitigate the damage and keep it functioning. Check out my Tail Light Repair DIY Guide for how to do that.
Needed
New tail lights (optional)
- Clear tail lights with black trim
- Clear tail lights with grey trim
New tail light infills (optional)
19mm socket
7mm socket
T30 Torx bit
Ratchets for the above sockets
Small flat-head screwdriver
Needle-nose pliers
Trim tool
About 1-2 hours
Before you begin
The tail light infill pieces have double-sided tape on their backsides. If you are removing the tail light infills and reinstalling them, or if you’re installing new infills that don’t have double-sided tape already one them, you’ll need to get new double-sided tape.
DO NOT over-tighten the nuts when mounting the tail lights to the car.
DO NOT apply different amounts of torque to each of the nuts when mounting the tail lights.
Overtightening the nuts or having uneven torque on the nuts are some of the leading causes for the seals to be broken on tail lights and condensation allowed to get into the unit.
I find it easiest to remove the the tail light infills trim pieces from the tail lights when the tail lights are still mounted to the car, because the tail light is most stable this way and it allows you to work with the infills without having to also manage the tail light simultaneously. The same is true for installing the infills on the new tail lights.
Step 1
Open the trunk of the car. Make sure the trunk struts are capable of holding the hatch open. If they can't you'll need to replace them.
Step 2
If you’re swapping the tail light infill trim piece to a new tail light, use the trim tool to remove it from the old tail light. Start at the trunk side of the infill and work your way outward toward the rear tire.
If the original infill is being used on the new tail light, clean the double-sided tape off of its backside.
Step 3
Remove the large black caps inside the trunk, directly behind the tail lights. Just twist them loose and they'll spin free. There are three on one side, and two on the other.
The nut that would be covered by the “missing” third cap is actually inside the cubby, shown in circled in the picture below.
Step 4
Pull back the carpet from behind one of the tail lights to fully expose the nuts and washers holding the tail lights in place. Use the 19mm socket and ratchet to remove the nuts and set the nuts and washers aside. There are thin foam gaskets behind the large flat washers. These are prone to breaking, so don't be surprised if they tear. I sell them in my Online Store if you need new ones.
Step 5
Pull the tail light away from the car until the wiring prevents you from going further, then rotate it to bring the outer corner even more to the rear to expose the wiring connector on the backside of the tail light. Use the small flat-head screwdriver to pull the red lock tab outward. When the red tab is fully to the side (it does not come out completely), the connector can be pulled from the tail light and the tail light is completely free from the car.
Step 6
Plug in the wiring connector for your new tail light, snap the red lock tab back in place, and slide the tail light into position on the car. Adjust the sleeves until the tail light sits where you want it to compared to the body panels around it, and make sure the sleeves are all even (the tail lamps shouldn't be able to wobble around).
Note: It is extremely important that the tail light fits flush and even when mounted. Using nuts to compensate for the “wobble” can lead to uneven torque being applied to the nuts and potentially cause the tail light sealant to break open, exposing the tail light to condensation and an early demise.
Step 7
Put the thin foam gaskets, washers, and nuts onto the back of the tail light inside the trunk, but don't tighten the nuts yet. Look at how this tail light compares to the one on the other side. There's a small amount of movement to them, so hold the new tail light in place to match the other side while tightening the nuts. Make sure the tail lights are positioned evenly and adjust accordingly.
Step 8
Apply double-sided tape to the backside of the tail light infill and carefully attach it to the tail light, starting on the outer edge where the tab is and slowly laying it down toward the trunk edge.
Step 9
Repeat Steps 2 through 8 for the other tail light if doing both tail lights.
If that’s all you’re doing, then you’re done!
If you’re also doing the CHMSL (third brake light) mounted in the trunk lid, continue to Step 10.
Step 10
Use a trim tool to remove the four fir tree clips closest to the latch on the underside of the trunk lid, then use the T30 Torx bit to remove the bolt holding the leather strap in place.
Step 11
Use the needle-nose pliers to remove the wire retaining clip on the CHMSL wiring plug, circled in the picture below. Be careful not to lose the wire clip! Then use the 7mm socket to remove the two nuts holding the CHMSL in place, being careful not to lose the nuts or washers.
Step 12
Remove the CHMSL and put the new one in its place. Use the 7mm nuts and washers to secure the CHMSL in the trunk lid, then reconnect its wiring connector and reinsert the wire retaining clip.
Step 13
Test the brake lights to ensure all are working. Make sure they work when pressing the brake pedal, using the left and right turn signals, rear fog lights (if equipped), and the hazard button.
Step 14
Put the carpet back in place behind the tail lights, and push the top edges of the carpets back into the rubber trunk seal. Then reinstall the large black caps. Put the carpet back in place on the underside of the trunk lid, using new fir tree clips and reinstalling the leather tab.
And that’s it!