Cracked Trunk-Mounted Brake Light

Tomko · #1 (**permalink**) 10-25-09, 07:45 PM

Wow, this is a new one on me.

I just put my DTS away for the winter today. In so doing, I closed the trunk lid a little more forcefully than I normally do. I always use the grab handle inside the lid, but this time I swung it down with a little more effort than usual.

When the lid slammed down there was this big crack sound, and now I have two cracks on the centre top of my CHMSL lens.

Anyone ever hear of this before?

I wonder if Cadillac will replace it under warranty...

Superjim · #2 (**permalink**) 10-25-09, 07:50 PM

Quote:

Originally Posted by Tomko

Wow, this is a new one on me.

I just put my DTS away for the winter today. In so doing, I closed the trunk lid a little more forcefully than I normally do. I always use the grab handle inside the lid, but this time I swung it down with a little more effort than usual.

When the lid slammed down there was this big crack sound, and now I have two cracks on the centre top of my CHMSL lens.

Anyone ever hear of this before?

I wonder if Cadillac will replace it under warranty...

Mo 2006 cracked about a year after I bought it.
It was replaced under warranty.

Jim

z06bigbird · #3 (**permalink**) 10-26-09, 02:05 PM

Be nice to service writer and service manager week!! I suspect that if you have a good relationship with service people, and ask them for their help with this problem, they might just cough up a new light. It all depends on your approach and how much prior business you have done with them.

What I mean is: The above will help.

hazcaddy · #4 (**permalink**) 10-26-09, 04:50 PM

There was a thread in this forum about 4 years ago on this subject. Cracked centre-mount brake lights, tail lights, and reversing lights. My '03 DHS came with a pre-cracked reversing light.

It has to do with the type of plastic GM uses - I'm surprised to hear that they haven't fixed the problem yet.

DevilleDeeman · #5 (**permalink**) 10-29-09, 04:54 PM

I replaced my LED trunk mounted brake light it cracked as well. It cracked where the mounting bolts are attached. Also found out that 3 LED's on each side were burnt out...so I replaced the whole light. I ordered it from NewGMParts.com online, cost me $120.00.

DTSdude · #6 (**permalink**) 11-01-09, 03:25 AM

The trunk mounted center brake light on my 2006 DTS has been replaced twice under warranty (before I owned the car). Not sure whats causing it but I have 4 theories at the moment,

1) The previous owner was slamming the trunk shut and the downward inertia causes the plastic brake lens to crack. The cracks are thicker at the bottom than the top which supports that theory.

2) The previous owner was shutting the trunk by pushing down on the brake lens. Very easy to do since it's right on the edge of the trunk. This is my favorite theory at the moment.

3) the lens is not curved the same as the trunk indent that it fits in. When the lens is installed the attaching nuts(bolts) are "bending" the lens into shape. Eventually, the lens starts the crack. Has anyone changed one of these on their own? Does the lens distort somewhat when the nuts(bolts) are being tightened.

4) heat/cold stress. Perhaps the heat or UV from the sunlight is degrading the lens plastic, plus I live in a cold climate (-30 C in winter). Sometimes it's freezing in the morning and +20 C and sunny during the day. That back and forth can't be good. But, why aren't the left and right lenses cracking the same way?

Anyone else have any theories or received an explanation from the dealer? I don't see any TSBs on this issue. My dealer denies it's an issue yet the 2 used DTSs he has on the lot both have the same problem. Most of the DTSs I saw when I was shopping around had the problem too (approx 6 other DTSs).

Thanks...............Ron

cubldr · #7 (**permalink**) 11-02-09, 03:12 PM

This was a routine warranty repair as I had the same problem of multiple cracks in the lens. Dealer service writer indicated this is a recognized problem

DevilleDeeman · #8 (**permalink**) 11-03-09, 05:15 PM

I noticed the new light I recently purchased curved a little more than the broken one I removed, it fit a lot snugger to the trunk lid.

DTSdude · #9 (**permalink**) 11-04-09, 12:34 AM

That's good news Deville Deeman. I just had a new one installed so hopefully that's the fix. In the mean time I don't slam the trunk shut or touch the brake light when closing it.

Thanks...........DTSdude

DevilleDeeman · #10 (**permalink**) 11-09-09, 05:22 PM

Quote:

Originally Posted by DTSdude

That's good news Deville Deeman. I just had a new one installed so hopefully that's the fix. In the mean time I don't slam the trunk shut or touch the brake light when closing it.

Thanks...........DTSdude

Just make sure they didn't over-tighten the nuts. They should be hand tightened and turned once with a socket wrench. I suspect the over-tightening will result in a cracked lens over time, it puts alot of stress on the plastic.