There are 2 main parts...the red lense which mounts from outside the trunk lid and the bracket which mounts from inside the trunk lid and positions the red lense for proper placement of the part. The bracket should fit snugy against the inside of the opening.
Third brake light replacement DIY
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when I first noticed the light was broke I went outside and the light was on the ground. So it apparently broke when my friend went into my trunK. So anyways I opened the trunk and took off the liner, the metal bracket seemed to have already been loose or out of place. So that's why I asked how exactly does it go. I know you mentioned the assembly should take place outside the trunk but I don't see how. I tried reaching for the metal bracket from outside the trunk and it's not working. Do I need to completely disassemble the metal bracket. The bolts are still on there...Im just having a hard time trying to figure out how the bracket stays in place...soon frustrating
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Thank you Keyhole.. you are a superstar!! I managed to change the light successfully using your guidance.
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I have 2004 clk 200.
I had received malfunction warning on the dash when my third break light stopped working.
I had received malfunction warning on the dash when my third break light stopped working.
Why? This thread is all about DIY.
1999 R170 SLK 230 Kompressor, 2005 W209 CLK500 AMG-Sport, 2007 GL450
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My recently obtained CLK500 ('05) has the warning light on the dash for 3rd Brake Lamp and is non-functional. This is really a bummer to me because I purchased the vehicle in a private party sale and cannot get the registration and license plates until the problem is fixed. (*Failed my Missouri state safety inspection because the 3rd brake light does not respond to the brake pedal.)
I was able to order a replacement part online and hope to get it next week to install and finish the process of getting my plates. Got the car a week ago but I can't drive it because I need the safety inspection to even get temporary tags in this state! So, I am in a Catch-22...I can't get the light fixed and I can't drive it legally without the light being fixed first! Arrrrggggghhhh!!! I want to drive my car!!! (Hopefully I won't have any trouble with this install...the trunk liner removal was simple and I can see the part - just an awkward angle to work from...
I was able to order a replacement part online and hope to get it next week to install and finish the process of getting my plates. Got the car a week ago but I can't drive it because I need the safety inspection to even get temporary tags in this state! So, I am in a Catch-22...I can't get the light fixed and I can't drive it legally without the light being fixed first! Arrrrggggghhhh!!! I want to drive my car!!! (Hopefully I won't have any trouble with this install...the trunk liner removal was simple and I can see the part - just an awkward angle to work from...
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Really good guide for installing the third brake light, thanks!
I bought a replacement from ebay (from lithuania - $130 AUD delivered to Australia)
Just a minor problem. When I was tightening it up, the Red plastic popped off the grey backing. Oops.
Had to epoxy it back together, wait for it to dry, then reinstall, with gentle tightening....
Just a minor problem. When I was tightening it up, the Red plastic popped off the grey backing. Oops.
Had to epoxy it back together, wait for it to dry, then reinstall, with gentle tightening....
2005 CLK55 AMG Coupe ,CLK320,Former,C180 Kompressor,Jensen Healey,Ford Capri V6,Alfa GTV.
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I also got one via ebay, Lithuania,but it was actually produced in Taiwan. The only difference to an original MB part was that the grey plastic had a few small extrusions that I had to trim off with a sharp knife. It had to be pushed quite hard to fit into the hole correctly,but after that it has been fine.
I would buy the same one again if I had to.,Half the price of genuine.
Some observations...
Having read through all the pages of this thread (wish I had found it before I did the repair on my third brake light!) there are a few points that may be useful to future readers.
It may seem obvious to those whose light has simply failed, but the assembly is a complete unit comprising red lens, white or grey rectangular 'container' and its enclosed circuit board. I think at least one person had the lens detach from the container and was thus confused as to how the unit was to be fitted, as you end up with a lens and a container with a metal bracket attached. The temptation is to take the new unit, attach the bracket, then try to work out how on earth this gets fitted! So, whether your unit broke into two parts or is still one, you need to remove the metal bracket in order to fit the new one - unit goes in from the outside, bracket goes on from the inside.
There have been questions raised about whether the lamp is 'tested' on ignition switch-on. Someone commented that the LEDs take so little current that it probably wasn't. True, the LEDs don't take much, but there are internal resistors across the rails to bump the current drawn up to 250mA, which is then tested by the system on switch-on. Without those resistors, the current drawn is only about 80mA which is probably too little. Wasted power, but only when you have your foot on the brake pedal!
Finally, the problem often starts with a crack in the lens. This allows moisture to enter the unit and that can kill some of the LEDs. I replaced 5 LEDs in my unit because they had gone high-resistance, knocking out half the total. I'm going to need a new unit sooner or later, but at least this gets me back on the road!
Having read through all the pages of this thread (wish I had found it before I did the repair on my third brake light!) there are a few points that may be useful to future readers.
It may seem obvious to those whose light has simply failed, but the assembly is a complete unit comprising red lens, white or grey rectangular 'container' and its enclosed circuit board. I think at least one person had the lens detach from the container and was thus confused as to how the unit was to be fitted, as you end up with a lens and a container with a metal bracket attached. The temptation is to take the new unit, attach the bracket, then try to work out how on earth this gets fitted! So, whether your unit broke into two parts or is still one, you need to remove the metal bracket in order to fit the new one - unit goes in from the outside, bracket goes on from the inside.
There have been questions raised about whether the lamp is 'tested' on ignition switch-on. Someone commented that the LEDs take so little current that it probably wasn't. True, the LEDs don't take much, but there are internal resistors across the rails to bump the current drawn up to 250mA, which is then tested by the system on switch-on. Without those resistors, the current drawn is only about 80mA which is probably too little. Wasted power, but only when you have your foot on the brake pedal!
Finally, the problem often starts with a crack in the lens. This allows moisture to enter the unit and that can kill some of the LEDs. I replaced 5 LEDs in my unit because they had gone high-resistance, knocking out half the total. I'm going to need a new unit sooner or later, but at least this gets me back on the road!
Thanks so much for the installation information I found on this forum. I just ordered the part, now let's see if I can DIY.
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Had this happen Day 1 of ownership. To me, shame on MB for making it so flimsy. I've learned to easily close my trunk lids since though.
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@keyhole: Nice try. But, ours popped out without closing the trunk -- or slamming it shut as you suggested. We were walking away towards a store and heard a "pop!". Turned around and there was the lens in two pieces on the ground. No trunk slamming involved, then or any other time. No need to slam as it closes quite easily. Thanks for the instructions on replacing the light, though.
2005 CLK55 AMG Coupe ,CLK320,Former,C180 Kompressor,Jensen Healey,Ford Capri V6,Alfa GTV.
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There is little doubt that slamming ,,or abruptly and forcibly closing the trunk lid ,,puts additional forces on the plastic ,,which then deteriorates over time , eventually resulting in cracks and fracturing of the lens...
That's not to say that there could be other exceptions after some 15 years of use...
You can close your lid as hard as you like...it's your car..
That's not to say that there could be other exceptions after some 15 years of use...
You can close your lid as hard as you like...it's your car..
Just purchased a 2008 CLK 550 and no more than 30 miles away from the lot the third light warning came on. Ugh. Ordered replacement. The install was easy but a pain. I ended up breaking on strap that holds the plastic cover over the trunk arm. Ugh. But I saved a bunch of money. Hopefully it will last. Thanks for the post and making me believe enough to give it a try. Now I can get it inspected.
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