Rear lights leaking - (not the upper (3rd) brake light!)

[feddomw]

Search gave no help unfortunately, but surely I am not the first one to come across this? All searches point to the 3rd light leak and water in the cargo area, that is not my issue.

Tow hitch specialist called me in to his shop during the install. He needed to drill a hole in my body for the install and when he did, a few gallons of water came out.....

We checked it out: there is a drain plug on the undercarriage. Pulled that out, more water. I assume it is also to prevent too much water ingress during deep crossings. Anyway, ton of water in there. We assume it's the gaskets on the rear lights, looking from the side with open hatch one can see there is a slight "crack"; enough to let water into the body cavity.

Anyone encountered this before? I will pull the lights ASAP, it's just 2 screws from the side I think, but I need to replace the gaskets most likely. I would prefer some sort of single sided tape to the light, thick enough and pliable enough to create a good seal against the body.

 

[n55luvr]

I had water pooling in same area you mention. I didn't drill a hole but soaked it up over a few dry days by stuffing towels into the cavity.

In my case, the weatherstripping around the entire rear tailgate had to be replaced. $65 for OEM stripping and dry as a bone now.

Best advice I can give is pull interior trim panels then have someone spray it down with a hose.

 

[Julian Stead]

I had to change my rear tailgate seal also, a lot more than $65 in the uk though.

 

[feddomw]

Thanks for the input. I think I may not have been clear though, as there is no way to get towels into the cavity.

Also, I don't see how a tailgate seal could be the problem, as that would allow water into the cargo area, right? I could be wrong though. Which seal did you replace?

 

[n55luvr]

In my case I pulled all the rear trim and I can see 2 holes that lead to a cavity under the rear cargo area. I had about 2 inches of water in there. The opening to this cavity is only about 2 inches on either side so it was a bit tricky stuffing towels in there but the cavity runs from one side to the other in the rear. Definitely thought about drilling a hole form the bottom but wasn't ready to be that invasive yet.

What was happening is that water would leak down the stripping and behind side cargo panel trim pieces. That was how water was getting into the cavity and also making the rear edge of the carpet wet.

Once I got to troubleshooting it was pretty obvious my rear weatherstripping had issues. It had visible crack at the 10:00 and 2:00 positions.

Part# = 67881-60111

 

[badlander]

You can access the lower cavity once you have the tail light removed. There is also a small plug in the bottom of the fender near the mud flap to let water out. I was wondering about new gaskets for the lights as well but did not find any mention of it in the FSM or exploded parts views. The gaskets are "sticky" and once you remove the light they are NOT as sticky. I really don't see how it could not leak once the gaskets have been disturbed. If anyone has a lead on new gaskets please post up.

 

[feddomw]

You can access the lower cavity once you have the tail light removed. There is also a small plug in the bottom of the fender near the mud flap to let water out. I was wondering about new gaskets for the lights as well but did not find any mention of it in the FSM or exploded parts views. The gaskets are "sticky" and once you remove the light they are NOT as sticky. I really don't see how it could not leak once the gaskets have been disturbed. If anyone has a lead on new gaskets please post up.

Looks like I will need to find some sort of foamy/gasket tape. Surely it exists somewhere, question is in what thickness. Option 2 would be to go for some doublesided tape, not as fun if you remove the lights at a later date, but sure to give a good seal....

 

[re_guderian]

Do you have rear AC? If so, check your drain.

 

[feddomw]

Do you have rear AC? If so, check your drain.

I do. Good point. I had checked it quite recently, but will do so again.

 

[cwmoser]

Appears that I am having the same problem.
I'm not familiar with the LX or LC - owner for just a month.
Do you have a photo of the drains for the rear AC and the drain plug you mentioned?

 

[feddomw]

I will take pics when I get the 100 back from the shop (for another issue) of the area affected and the drain plug.

The rear AC drain you can search the forum, there is a pic posted somewhere. It's quite hard to find without the pic to guide you. It's on the rear passenger side and is rectangular with a small slit. THis to prevent water ingress (we presume).

 

[cwmoser]

Thanks. Regarding those drain plugs, does it make sense to just leave them off or at least
drill a small hole in the plug so water can drain out? Just pondering. I know on the
Mercedes 560SL's their is a rubber drain plug with a slit in it - that plug is located
in the trunk spare tire compartment.

 

[feddomw]

Thanks. Regarding those drain plugs, does it make sense to just leave them off or at least
drill a small hole in the plug so water can drain out? Just pondering. I know on the
Mercedes 560SL's their is a rubber drain plug with a slit in it - that plug is located
in the trunk spare tire compartment.

I was thinking the exact same thing! I will pull mine and leave them out I think. I don't do deep water crossings and I don't understand the logic of not letting it drain if any water gets in there.

 

[Julian Stead]

In my case I pulled all the rear trim and I can see 2 holes that lead to a cavity under the rear cargo area. I had about 2 inches of water in there. The opening to this cavity is only about 2 inches on either side so it was a bit tricky stuffing towels in there but the cavity runs from one side to the other in the rear. Definitely thought about drilling a hole form the bottom but wasn't ready to be that invasive yet.

What was happening is that water would leak down the stripping and behind side cargo panel trim pieces. That was how water was getting into the cavity and also making the rear edge of the carpet wet.

Once I got to troubleshooting it was pretty obvious my rear weatherstripping had issues. It had visible crack at the 10:00 and 2:00 positions.

Part# = 67881-60111

Same as mine, I didn't have a wet carpet but there was a smell. I only noticed it when I fitted a liner and it condensated under it.

 

[ZwhoHeBe]

In my case I pulled all the rear trim and I can see 2 holes that lead to a cavity under the rear cargo area. I had about 2 inches of water in there. The opening to this cavity is only about 2 inches on either side so it was a bit tricky stuffing towels in there but the cavity runs from one side to the other in the rear. Definitely thought about drilling a hole form the bottom but wasn't ready to be that invasive yet.

What was happening is that water would leak down the stripping and behind side cargo panel trim pieces. That was how water was getting into the cavity and also making the rear edge of the carpet wet.

Once I got to troubleshooting it was pretty obvious my rear weatherstripping had issues. It had visible crack at the 10:00 and 2:00 positions.

Part# = 67881-60111

Im getting a slow leak that is behind the passenger side cargo panel under the tilt window. i had tightened that window latch bc it was loose thinking it was the issue. Nope! Still getting it. What stripping are you referring to? The roof stripping under the roof rack? Thanks!

 

[Detailx]

In my case I pulled all the rear trim and I can see 2 holes that lead to a cavity under the rear cargo area. I had about 2 inches of water in there. The opening to this cavity is only about 2 inches on either side so it was a bit tricky stuffing towels in there but the cavity runs from one side to the other in the rear. Definitely thought about drilling a hole form the bottom but wasn't ready to be that invasive yet.

What was happening is that water would leak down the stripping and behind side cargo panel trim pieces. That was how water was getting into the cavity and also making the rear edge of the carpet wet.

Once I got to troubleshooting it was pretty obvious my rear weatherstripping had issues. It had visible crack at the 10:00 and 2:00 positions.

Part# = 67881-60111

@n55luvr I've got exactly the same problem. Is there a trick to installing the weatherstrip. I've had the rear hatch weatherstrip all the way off and attempted to reinstall with the 3M weatherstrip adhesive, but still leaks and I can see the water coming down the outside of the weatherstrip up top then ending up on the inside of the weatherstrip on the bottom like a gutter funneling water into the channel beneath the body. I notice there are various clips and drainholes in this weatherstrip. I'm debating on buying a new one as I think it may just be an issue that it's on there wrong. There is no outright damage. The seal seems fine except it doesn't seem to pinch down on the pinch weld hard enough anymore to keep it sealed.

 

[Slimm]

@n55luvr I've got exactly the same problem. Is there a trick to installing the weatherstrip. I've had the rear hatch weatherstrip all the way off and attempted to reinstall with the 3M weatherstrip adhesive, but still leaks and I can see the water coming down the outside of the weatherstrip up top then ending up on the inside of the weatherstrip on the bottom like a gutter funneling water into the channel beneath the body. I notice there are various clips and drainholes in this weatherstrip. I'm debating on buying a new one as I think it may just be an issue that it's on there wrong. There is no outright damage. The seal seems fine except it doesn't seem to pinch down on the pinch weld hard enough anymore to keep it sealed.

I’m pretty sure the orientation for the large weatherstrip (pn 67881-60111) is with the three cutout holes centered on the bottom, but looking for confirmation as well. It’s reinforced, thicker in some spots, etc so I believe correct installation is crucial to maintaining a water-tight seal.

 

[Detailx]

@Slimm thanks. So piecing together several pieces of information including guidance from my buddy who is a Lexus tech, here's what I went with. Centering the pink line on the factory gasket on the bottom of the opening yielded what you had said about the three drain dots going across the bottom of the opening. Doing this also places the reinforced areas of the seal right where the chunky pinch weld comes together on each upper corner. You could theoretically put the gasket on two ways. What you want it is the side with the double seal to push into the body to form a sort of gutter for the water to flow down. The OEM gasket comes with adhesive already inside (some of mine was stuck together with it), but after getting the opening spotless, I used an adhesion promoter swab (probably overkill). It's worth noting while you have this off to inspect all of the seam sealer for any cracks or penetrations. Alot of welds come together in this door opening. If you have holes seal with the 3M heavy drip check and paint over. Stuff works amazing. Just finished the job so can't say for sure whether it will hold up, but the really solid sign is that the clamshell back door used to push in considerably with the old seal there. Now it barely moves. While the old seal looked fine, the new seal is considerably more pliable and swollen. This is important to get right because the roof funnels water down each side of the hatch door. If you haven't seen, it flow a bunch of water up on your roof then open the back door. It is a legitimate waterfall.

 

[Slimm]

@Detailx I just posted a reply to my thread on this issue but I figured I would let you know that the water seems to be coming in from the channel inside the main tail lights, from somewhere above. It drips down from behind where the tail lights mount, down to the cavity with the two 3" openings inside the rear hatch area. Not sure if you fixed your issue or not, but the pinch welds seem to be guiding water into that cavity. Very odd, will update if I find out how/why the water is coming in.

 

[Detailx]

@Slimm thanks for the heads up. After a couple of good rains, the hatch seal seems to have done it (knock on wood). I had previously considered it being the roof rack mounts since I'd had it off so sealed all of those with the 3M Dripsealer before replacing the hatch seal. It may be those. There are the mounts you can see under that plastic strip when you pull up the feet then another set underneath the plastic strip for what I'd guess is an alternate mounting arrangement for a different roof rack. That whole channel was full of water when I pulled the plastic strip (slide it out the back). May want to give those a look if not already as they would flow into the taillight cavity.