Sealing Aftermarket Taillights

[ladysi]

Ok, so I ordered and installed the led sequential smoked taillights last year.



I don't even think they are really available anymore either, probably for good reason... my drivers side upper trunk portion got water in it over the winter and half shorted out. I bought a second set a few months ago but have been to busy to swap them. The time has come though.

This time around, I want to fully seal the full set. I have picked up some thin plastic folders, a small piece of 0.060" acrylic, and some shitty 0.25" rubber grommets. I also have liquid electrical tape and cleat rtv silicone.

The larger lights, those that fit onto the car onto either side of the trunk, can most likely be sealed around the edges with some silicone and the cables protruding from the back side of each harness connector can be given since extra liquid electrical tape for good measure.

My question concerns the smaller trunk lights, as those seem more susceptible to waterlogging - at least I have first hand empirical evidence to that fact. I can, like the larger lights, seal the edges with silicone and touch up the connector cables with liquid electrical tape.

What i am concerned about are the large holes in the back through which the cables run.

My thoughts are:

1. Remove the foam around the hole.
2. Cut plastic/acrylic pieces to the same size as the outer dimension of the foam.
3. Drill a hole in a piece of plastic/acrylic big enough for the rubber grommet.
4. Insert grommet in plastic/acrylic.
5. Cut the wires from the taillight.
6. Run the wires through the grommet.
7. Solder the wires back on with a lineman's twist joint and heat shrink the joint.
8. Silicone the plastic/acrylic over the hole. (Or use epoxy if the silicone does not hold).
9. Silicone/liquid electrical tape any remaining gap in and around the grommet.
10. Stick the foam piece back on.

My questions to this forum:

1. Would it be better to use really thin plastic (think plastic folder/divider from office max) or acrylic (thicker, stiffer, from menards)? If so, why?

2. Which parts of this process are best with silicone vs liquid electrical tape vs epoxy.?

3. Any tips for using rtv silicone or any other silicone for that matter when it concerns sealing the edges? I am concerned about keeping the look clean and hoping that the seal is completely hidden/transparent.

BONUS: Any doubts, suggestions, etc about my thoughts above?

 

[ladysi]

I am purchasing these headlights on Friday.

Well, I think we have a vested interest. They are great looking. Even though I had one leak so far, I bought a second set. Now I am covered for some time. I plan to fix the current bad one too.

The negative about acrylic is working with it. Only straight line cuts.

 

[ladysi]

Im buying them and live in New York, I am not going to seal mine. Hopefully ill be ok.

Well I wish you all the best of luck. The first melt and refreeze left me with about an inch of ice in one of them. Could be a rare defect or could be something like an issue with a manufacturing process. My suggestion would be to at least tape up the hole in the trunk pieces.

Anyways, they are mighty sharpe looking lights, I hope to get mine sealed up soon.

 

[mjdecker]

I got these about a year ago and have thought about this but haven't done any sealing. It survived the winter at least but it's still something I've been meaning to do at some point.

 

[ladysi]

I got these about a year ago and have thought about this but haven't done any sealing. It survived the winter at least but it's still something I've been meaning to do at some point.

I park outside (no garage), so winter is really harsh on my car. How bad are your winters?

Also, any thoughts about my sealing method above?

 

[mjdecker]

I park outside (no garage), so winter is really harsh on my car. How bad are your winters?

Also, any thoughts about my sealing method above?

I imagine your winters are much harsher than mine but we do get some decent precipitation throughout weather it's rain or snow. Temperatures one week can be 10 degrees and then 50 the next day. The north east is weird.
My Civic is also not garaged (other car in my list gets that luxury).

As far as your method, you are going far and above on what I had planned but it looks like it'll protect it well. All I was planning on doing was to go ham with electrical tape around the connectors.

 

[Syntek]

Out of curiosity, when your previous taillights shorted out, how much water were in the actual housings? I'm wondering if maybe condensation fried the board from the ice sitting on-top of the lights for too long and if that's the case, how effective will the sealing be?

 

[ladysi]

Out of curiosity, when your previous taillights shorted out, how much water were in the actual housings? I'm wondering if maybe condensation fried the board from the ice sitting on-top of the lights for too long and if that's the case, how effective will the sealing be?

There was like 1.5 inches of water. I doubt it was from condensation as the other trunk taillight was fine.

 

[ladysi]

One working light, and the other in in its shorted state. I wish I got a picture of the water in the taillight. I pulled the light and drained it (it would drain from multiple locations), but the damage was done. It existed as ice for a few weeks until I could find a long weekend to pull the light, heat it up, and drain it. If I had caught it right away I may have been able to save it without much hassle.

I do plan to bake the taillight to open it up and perform some smd repair, as I now have a full second set, if I can save it, I will have a full backup set. Of course I will seal it if I need to swap.

View attachment 153642

 

[ladysi]

Sealing process:

Step 1:

Cut the wires from the trunk pieces about half way down the wire (leaving room to solder them back together.

Step 2:

I had issues with the acrylic - that shit is hard to score and then break cleanly, especially when trying to do so to such a small irregular shape. I didn't like the flimsiness of the divider plastic from Office Max either, so I opted to use plastic packaging - you know the stuff that we as a society wrap everything in?

I cut it to the desired size - just a bit smaller than the inner dimension of the upper rim around the hole on the back of the trunk lights and then used a hole puncher to punch out the hole to match the location of the wires.

Step 3:

Heat shrink the base of all three wires - this will help protect them from chafing on the plastic.

Step 4:

Run the wires through the hole in the plastic.

Step 5:

Use a lineman's joint:

to solder the wires back together - Remember to cut and insert the heat shrink before you solder the wires back together!

Step 6:

Apply the liquid electrical tape to backs of the plastic harness sockets - use liberally! I would suggest waiting 5 minutes after the first coat and then applying a second.

Step 7:

Silicone time - apply a liberal amount around the clear plastic piece and on the hole through which the wires run. I cut the just the tip of the applicator tip off to the smallest bead size possible.

View attachment 153653

Step 8:

More silicone. Squeeze a thin bead around all 4 lights where the clear (smoked) plastic lens meets the black frame plastic. Then run your pinky along the bead to press the silicone into the seam. Be careful not to use too much silicone, you can always apply a little more if necessary, but too much will become a mess.

I also applied silicone to any screws (as I don't trust the cheap gaskets) and bolts running through the rear of the lights.

View attachment 153655

Step 9:

WAIT!!!!!! at least 24 hours for the silicone to cure. then you should be all set.

Once mine cure I will take some final pics of the lights - including some of the sealed areas and some of the front of the lights. Hopefully the seal holds and the clean look from the exterior has not been altered.

 

[ladysi]

I imagine your winters are much harsher than mine but we do get some decent precipitation throughout weather it's rain or snow. Temperatures one week can be 10 degrees and then 50 the next day. The north east is weird.
My Civic is also not garaged (other car in my list gets that luxury).

As far as your method, you are going far and above on what I had planned but it looks like it'll protect it well. All I was planning on doing was to go ham with electrical tape around the connectors.

Ham for sure. The connectors on my old set has signs of corrosion too. I wonder if the water followed the lines in... If this was a boat I would be using drip loops religiously, but alas, cars have very little room to accommodate such things.

 

[joshhjackson2112]

You now have me concerned! I just bought a set of taillights and had no plans of doing any preemptive maintenance. I dont have a soldering gun so I may not be able to go as great into detail as you did. But I might! Very good write up btw. This will help me astronomically if I decide to go this route step by step. I hope it works!

 

[ladysi]

You now have me concerned! I just bought a set of taillights and had no plans of doing any preemptive maintenance. I dont have a soldering gun so I may not be able to go as great into detail as you did. But I might! Very good write up btw. This will help me astronomically if I decide to go this route step by step. I hope it works!

Most welcome! I totally knew nothing about cars and aftermarket stuff 1 year ago.... then I learned my lesson. You could just slather silicone into the holes, though wait longer for them to cure if you use very much. My suspicion is that water dripped down the wires into the lights, thus why I am taking precautions this time around.

Clear RTV silicone is cheap and available at most auto/hardware shops.

I have been working with small electronics for 25+ years, so soldering was the easiest and quickest of all the steps for me. But I get it, it can be daunting. I just like to do everything as "correct" and anal as possible.

I am glad you are reconsidering...if I had known about issues with aftermarket parts a year ago I would have saved 400+ bucks on my second pair of taillights.

Best of luck!

 

[ladysi]

Since pics of the cute and final result before I installed them last night. I even did a submersion test on the right trunk light (sorry, no pics of that - facepalm). They look nice, and seem solid. It was raining really hard on and off yesterday and will through this week, so it will be tested. I did get a touchless wash last night and the lights are still bone dry inside....so this may be a total success.

I took some photos of the install process flogger the tail lights, but I will open a new thread detailing that.