A water leak in the trunk

[bigvettefreak]

I had LED tail light units installed in my 2000 740il a while back and today, after I went through a car wash, I found that the spare tire area is soaked and I looked at the right side battery area at the tail light and it looks like there was water in that area as well.

I thought it might be the trunk gasket, but the carpet and surrounding area was dry.

The lights came with gaskets etc. but it appears they may be the problem.

Anyone have this problem and are there any ideas as to how I can seal the lights to stop the leak?

[cazal740i]

thats an easy 1..lift your spare tire out and check the plastic plugs on the bottom...Either ur missing 1 or forced jet water seeped thru

[Timm]

After-market rear light clusters often leak - remove them and use silicone grease (not sealant) profusely on the seal and sealing surfaces. Be careful of leaks from the clusters, the water can damage the electronics on the LHS (audio, phone etc)....

[bigvettefreak]

After-market rear light clusters often leak - remove them and use silicone grease (not sealant) profusely on the seal and sealing surfaces. Be careful of leaks from the clusters, the water can damage the electronics on the LHS (audio, phone etc)....

I have copied your suggestion and will give it to my INDY. He installed them, he can re-install them with the needed additional grease.

Thanks for your help.

[Edwin NL]

I had the same leak, nothing wet but the spare area was always wet.

I pulled the rubber trim (were the trunk closes on, like door rubber) sorry don't have the word for it

And found that 2 corners were bent down a bit and the trim did not match up to the trunk anymore.

Changed the rubber and ever sins no more problems

[bigvettefreak]

It is raining today so I opened the trunk and I could see the water running in behind the lights. I looked at the original lights and they have a gasket that fits against the body that the new ones did not have. I call my INDY & he is going to fix it. May have to buy the rubber moulding tape you use around windows and make a gasket.

[Edwin NL]

Gaskets can be bought from the dealer

[bigvettefreak]

Thanks, I will stop there Monday.

[TestShoot]

Man this is common, I have condensation inside my aftermarket tails, also had it in the OEMs, also on the right side.

[bigvettefreak]

I called the dealer and ordered the gaskets for both sides, they were $22.00 and change each.

I am also going to check the seal of the lens against the main body as well and use some sealer if I find anything I don't like.

I will also use silicone grease on the rubber gasket (body contact side) to assure a nice tight seal.

Thanks for the great info Edwin

[Rhein Amacher]

I am going to try to install the OEM gaskets on my aftermarket to eliminate the water/condensation going into the left tail light housing. It turned off my radio/navigation unit again today and screwed up the left/right turn signal in my cluster. Hate that the aftermarket LEDs have no gaskets or insulation from water seeping through.

[aom7]

My LED celis had a huge/thick foam pad that (once screwed down) completely sealed itself against all the holes. Are you saying that yours had no foam or gasket at all?

[Rhein Amacher]

Mine has a foam gasket, but unfortunately I do not live in sunny and water drought So Cal. I live in rainy and cold Portland, Oregon where it rains half of the year. Water is still getting into the ibus connection and causing a short in the left tail light housing. I might try to put the old gaskets on there to see if that changes anything. I don't know which one is the ibus connection back there so I can clean it and get all the moisture out.

[Rhein Amacher]

Will the OEM gasket work as a sealant for the LED tails? I want to replace the crappy foam sealant that the LED tails came with.

[740iSport303]

If they have the same ridge as the OEM tails and you can mount the gasket properly, then yes it should work.