Third Brake Light Cracking

[rennwerkes]

The third brake light lens on my 2013 135i with only 34k on it has started to crack.
I took it into the dealer and asked them if this could be covered under my extended warranty. They were quick to deny my request.
What do you guys think? To me, this is definitely not a wear and tear item and shouldn't exhibit cracks so soon. Or am I wrong?
Thanks!

[Rikx1M]

Originally Posted by rennwerkes

The third brake light lens on my 2013 135i with only 34k on it has started to crack.
I took it into the dealer and asked them if this could be covered under my extended warranty. They were quick to deny my request.
What do you guys think? To me, this is definitely not a wear and tear item and shouldn't exhibit cracks so soon. Or am I wrong?
Thanks!

Do a search for 3rd brake light service bulletin, print it out and take to BMW. There is a well documented problem with these lights....

[NorthernDancer]

This happens to all 1 series. I think your car is too old now to get a free replacement but do search for the bulletin (right here and via google). Mine was replaced once or twice under 1st owner. Mine is cracked now. Stayed that way for years but last year I put a bead of Gorilla glue on it. I also have a new one just in case this cracked one goes really bad.
This 3rd light is unique to the 1 series so eventually new supply will dry up.

[Gangplank]

It depends on what your warranty covers. If it's CPO and bumper to bumper then it might be covered. If it's aftermarket like mine it's probably not covered.

That said the light is pretty inexpensive on Amazon and/or FCP Euro's site. I replaced mine and it was pretty easy to do. $50 for the part and about 30 min of my time.

Here is a thread. On page 2 or 3 there are links to a DIY by Dackel.

Gd.Dam Third Brake Light https://www.1addicts.com/forums/show....php?t=1496808

[rennwerkes]

Thanks everyone for the info.
My warranty is CPO but dealer said no to replacement.

[gjm120]

I was thinking about buying one put in my spares for when mine breaks. Any guidance on whether BMW genuine or aftermarket like Dorman is the way to go? There is about 2x price difference for the BMW genuine.

[rennwerkes]

Is the Dorman part still available?
I can't seem to find it.

[gjm120]

Originally Posted by rennwerkes

Is the Dorman part still available?
I can't seem to find it.

I found it on ebay and at Parts Geek.

[Gangplank]

It's available on Amazonia and other sites. You might even be able to order it at Autozone...

[rennwerkes]

How are you guys searching for it on Amazon?
I've tried and come up with nothing.

[rennwerkes]

LOL! I found it on both Amazon and Ebay.
I was using the BMW part number when I should have done a more generic search.
Thanks!

[Jason G]

Can somebody tell me the size of the 3rd brake light lamp nut? My replacement lamp is oem from ECS and the threading of the post is different from the original. Thanks!

[NorthernDancer]

http://www.realoem.com/bmw/enUS/part...&q=63259128043

M5; it's been on almost every BMW since 1972.

[Horigan]

To improve longevity of the new light, don't crank the nuts all the way down and fully compress the spring. Just compress the spring a little bit so that the perimeter foam creates a seal. I think over torquing the nuts is a major factor in cracking this weak design.

[rennwerkes]

Can someone confirm if installing a new lens requires new nuts? Or can you just reuse the original nuts? I recall someone mentioning that the threading is different.

[dtla1]

Re-use, Not sure where why that one person above said it was different.

[rennwerkes]

Updating this thread.
Bit the bullet and bought a factory lens. Also bought new springs (because most of the DIY's mention that) BUT my springs were already updated. Not sure if it's because my car is a 2013 (late production) or because it's been changed before.
What was even more interesting is that the lens fit perfectly. Others were mentioning that you had to modify the lens to get it to fit. I guess I lucked out with my car so no mods necessary. Pretty straight forward and took very little time. No gotcha's at all.
One interesting observation was that the nuts on the original lens were really tight! To a point where I unscrewed the the mount out of the light. I have no idea why anyone would want to tighten it that much. In fact, I could finger tighten the nuts all the way down to the base and then I back off a bit hoping it'll prevent future cracking. Now I just hope it won't leak.
I did clean the opening of any residual dirt and dust.
Thanks again for all the advice and comments.

[atch417]

Mine is also cracked on a 2011 with 41k miles 🤬

[PCNewman]

Anyone figure out a way to prevent or at least prolong this issue? I thought about hitting it with a heat gun prior to install to help it mold to shape.I'm replacing mine after 16 months. Thinking Doorman or China next time around.

[BMWCCA1]

Originally Posted by rennwerkes

Others were mentioning that you had to modify the lens to get it to fit. I guess I lucked out with my car so no mods necessary.

BMW made modifications to the trunk lid at some point and the "tab" in the brake-light opening was removed. The replacement lamp BMW supplies now won't fit the trunks with the tab. The factory bulletin for replacement instructs to grind off the tab on older cars but I didn't like the idea of introducing rust into an historically vulnerable area on older BMWs when I replaced the light on my wife's '08.

This is what I used which will fit both versions, it is inexpensive, requires no modifications for either version, and cannot be distinguished from the OE part:
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

You can see my post on the thread here. I also replaced the springs, but the nuts worked on the new light perfectly

[rennwerkes]

Originally Posted by PCNewman

Anyone figure out a way to prevent or at least prolong this issue? I thought about hitting it with a heat gun prior to install to help it mold to shape.I'm replacing mine after 16 months. Thinking Doorman or China next time around.

I did notice that the nuts on my original lens were really tight upon removal. So on the install I just snugged the nuts down gently and so far no problems.

[c0bra]

Originally Posted by rennwerkes

One interesting observation was that the nuts on the original lens were really tight! To a point where I unscrewed the the mount out of the light. I have no idea why anyone would want to tighten it that much. In fact, I could finger tighten the nuts all the way down to the base and then I back off a bit hoping it'll prevent future cracking. Now I just hope it won't leak.

Recently replaced mine, and the nuts were on way too tight. I ended up pulling out 2 mounts and couldn't even get the nuts off the mounts, so I was lucky I had replacement nuts. The prior replacement was done at a dealer.

Originally Posted by PCNewman

Anyone figure out a way to prevent or at least prolong this issue? I thought about hitting it with a heat gun prior to install to help it mold to shape.I'm replacing mine after 16 months. Thinking Doorman or China next time around.

Recently installed, so idk how long it's going to last... Hand tightened the nuts from inside out (torque is supposed to be 2.5 Nm), filed down the tab more than it already was (dealer had filed some and used new springs), and used Dremel to remove notch on OEM replacement.

https://www.newtis.info/tisv2/a/en/e...lights/PoMpSk4