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Discussion Starter #1 (Edited)
I'm sure some of you Cobra owner's have concerns about your 3rd LED brake light may have the possibility of failing at some point in time... (especially if you daily drive the car).

Is there any repair info available online for the 94/95 specific Cobra 3rd brake light? How can it be repaired if 1-2 (or more) LED's are not functioning when the brake light is "on"?

I just noticed that (1) of the internal LED's on mine (towards the center of the light) is not functioning...

I thought that LED's do not wear or blow out (like a standard light bulb)?

My guess is that at the location of that particular LED, there may be an issue with the actual circuit board. ?
 

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Well, LEDs do wear out eventually, just no where near as fast as an incandescent.

I think there's a service panel under the wing (I can't remember). If so, you'll just need to get some similar LEDs, remove the old ones, and re-solder in the new ones.

That may seem a little simplified, but you can Google "LED install" and "LED circuit" to get the general concepts down. Hopefully, all you'll have to do is replace the LED itself and none of the other stuff.

Sorry that doesn't help you more.
 

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Phil, just remove the wing and take off the service panel. LED's are usually good for 100,000 hours. My 95 has a bad solder joint on one LED and it flickers.
 

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None of mine work, any idea of where to get an LED to swap in?
 

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There was some talk about this a while back. IIRC, a fellow on here even repaired his. I'm sure a search would bring it up.

Jason
 

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I've repaired mine before. The tricky part is that the LEDs that are in there are not regular old LEDs, they are something called "flux LEDs" They are very small, very bright, and each one is mounted to a small circuit board.

Heres how I did it. It was a pain in the you know what by the way:

-remove wing
-remove panel covering LED bar
-remove LED bar and pull wiring with it.

-the LED bar is sealed. You have to cut it open. I used a moto-tool with a thin cutting disc attachment to slice a line all the way around the grey plastic, making sure I left enough space to seal it back shut later. Try not to go too deep and damage the LEDs on the inside.

-At the time, I had no idea what those flux LEDs were, so I put regular ones in there that I got off ebay. You can get a GREAT deal on LEDs straight from the manufacturer in HongKong on ebay. Note, it takes like 2-3 weeks to get them shipped. They are very good quality. Just make sure you get the brightest ones you can find.

-I forget how the LEDs are attached on the inside, but you can remove them all. Go ahead and remove them.

-Now, the new LEDs I used are larger than those small flux LEDs. Using the moto-tool again, this time with a pointed attachment, I enlarger the holes just big enough to fit the normal LEDs in snugly.

-Put a dab of superglue on each LED to hold it. Now, wire in each one.

-seal the case back up. I used silicone sealer.

-Anotehr tricky little thing. When I plugged it back into the car, the LEDs werent lighting up. I'm gonna share a little morsel with you here. There is a resistor in the wire going to the LED bar. I just replaced the whole length of wire with some speaker wire I had laying around and presto, works like a charm.

-Now, it isn't EXACTLY right, because of that whole resistor thing. The LED bar is on all the time but pretty dim. I actually love the way it looks. And it is very bright when you press the brakes.

-You could put a different resistor in there to make it just like the stock LED bar, but I like it just the way it is. Would take a little experimenting with different resistor values. Trust me, it looks good.

If anyone has any questions, email me (ni.kruse at gmail dot com)
 

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There is a resistor in the wire going to the LED bar. I just replaced the whole length of wire with some speaker wire I had laying around and presto, works like a charm.

-Now, it isn't EXACTLY right, because of that whole resistor thing. The LED bar is on all the time but pretty dim. I actually love the way it looks. And it is very bright when you press the brakes.

-You could put a different resistor in there to make it just like the stock LED bar, but I like it just the way it is. Would take a little experimenting with different resistor values. Trust me, it looks good.
or just use a multimeter and measure the total resistance of that one wire. head to Radio Shack and see if they've got a resistor close to that value, cut the old one out, solder and heatshrink the new one in place and Presto!, you're done.
 

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or just use a multimeter and measure the total resistance of that one wire. head to Radio Shack and see if they've got a resistor close to that value, cut the old one out, solder and heatshrink the new one in place and Presto!, you're done.
Well, if that was the case, you could just leave the original resistor/wire in place. What I am saying is that the new LEDs I used come with resistors to run on 12v. The flux LEDs run off a different voltage. So you need to use a different rated resistor to match the exact brightness of the flux LEDs
 

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Well all of mine work, turns out 1 of the 2 harness wires was cut and had electrical tape around it, like something was spliced in long ago, no idea why. :rolleyes:
 

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Well I haven't be able to find a working third brake light for the crab claw... So I broke down and cut the light open, and I have been brain storming on what to cheaply do to fix this. Here are some pictures for other people like me thinking about cutting into this. I think I might just wire up some incandesent bulbs from a rope light that I have laying in the shed. Pictures included are the routing of the wires, which I cut into a little... side profile, and shot of the board and the flux style LED lights.
 

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sublimobile, do you know what voltage was presented to the LEDs?

mckchr67, send me dimensions, schematics, better pics, and maybe I can help with a fix.
 

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sublimobile, do you know what voltage was presented to the LEDs?

mckchr67, send me dimensions, schematics, better pics, and maybe I can help with a fix.
Not sure I understand what you are asking. I am not sure what voltage was running to the original 3rd tail light or the resistance. If mckchr67 can put a voltmeter on the red wire and check, that would be the easiest.
 

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Well I haven't be able to find a working third brake light for the crab claw... So I broke down and cut the light open, and I have been brain storming on what to cheaply do to fix this. Here are some pictures for other people like me thinking about cutting into this. I think I might just wire up some incandesent bulbs from a rope light that I have laying in the shed. Pictures included are the routing of the wires, which I cut into a little... side profile, and shot of the board and the flux style LED lights.
You won't be happy with the rope light. It wont be nearly bright enough. If you pull out the strip of FLUX LEDs, you will be left with the reflector and the silver backing. Each LED has its own little hole. It is very easy to drill them out and snugly fit an normal LED in place.Also, use a dot of superglue for good measure. Not too much though, cus you might need to pull it out later.

The LEDs can be bought very cheaply on ebay. Just look for 5mm, as bright as you can find. You can get a set of 100 pieces with 100 resistors (designed to work with 12v) for around $20. Takes a few weeks as they ship from Hong Kong but they are a steal. Then you just wire up each LED with a resistor and you're on your way. Its time-consuming, but not difficult.

I wish I took a picture while I was doing it. Have to make sure it all fits back inside the case when you are done.
 

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sublime: any links?

Your info is very helpful. With your install, you said that the leds are always on?

(LOL, I wonder if kids today pronounce it L-E-D Zeppelin?)
 

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sublime: any links?

Your info is very helpful. With your install, you said that the leds are always on?

(LOL, I wonder if kids today pronounce it L-E-D Zeppelin?)
sorry, no links. I did it from scratch and I didnt take any pictures. I wish I did, cus it came out so nice. Hard process to describe but it's really not that difficult to do if you have ever wired up LEDs before. Lots of soldering.

Yes, with mine, the LEDs come on when I turn the car on. Let me try to explain more clearly.

Original setup has Flux LEDs, with no resistors on the flux LEDs. There was however a resistor in the power line running to the 3rd brake light.

With my setup, I use normal LEDs, with a resistor on each LED. I originally plugged it in and didnt understand why it didnt work. After much thought, I started measuring voltages. I noticed the voltage at the third brake light was less than the voltage where the wire plugs in to the harness. So I concluded that there is a resistor in the line. Sure enough, I cut off the plug and wired it onto the 3rd brake light with seperate wire and plugged the whole unit back in. Worked.

However, the light is now always on because my resistors did not equal the resistor in the original wire. But the voltage was safe for my LEDs and I like how it looks, so I was fine with it. The 3rd brake light is very dim normally. When I step on the brake it is noticeably very much brighter. You really only notice the dim lighting at night.

Here is what confuses people I think. Because I was running a different kind of LED (and at the time I didnt understand that there was a resistor in the original wire), I wired up each individual LED with a resistor. You may not actually need to use resistors with your LEDs, but in that case you need to compare the voltage into the 3rd brake light with the voltage that is proper for the LEDs you are using.
 

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I am on my phone at work, but what I meant with the rope light was cutting it apart and using the individual light bulls on a parallel type wiring in the individual holes in the light housing. So that would be just as bright as what the flux LEDs were if not brighter. So less soldering compared to LEDs with resistors on each light. My board was also fried from water exposure I could assume. So I have no power going through the board, I tested the individual flux LEDs and only 4 of them worked. I was planning on going to a hobby shop to look for led strips that have the same spacing as the original board.
 

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Alright I have been playing around with the light set up for the last three hours. To start with the dimensions. The board that the factory LED's are on is 5/16" wide, 12-5/16" long, depth is 1/4" from flat of LED to tip of pig tail out the back of the board. The LED spacing is 5/8" center to center. The resistor that is in line on the wiring harness appears to be a 720 ohm resistor for 20 flux LED's. I did a really quick wiring of the incandescent lights from rope light also, and they were surprisingly bright. All I did was strip single speaker wires and make a parallel set up with taping it to the leads on the lights for a quick mock up. Even if i would have soldered and did this neatly, I don't think it would have fit back in the case. Here are some pictures.

resistor cut open, the label was hard to read but with calculations I could believe that it is a 720 ohm



light bulbs pulled out of rope light with leads connected in series.


spoiler off


with incandescent lights from my wifes stupid rope light from her dorm in college... with no resistor just on 12v in parrallel wiring.
 

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This way of fixing is for the cheap lazy person I guess, but it at least gives some insight for those wanting a weekend project. If I can find friend with a good soldering iron, and decide I have the time this winter... I will go the LED route, but I still don't know how this is going to fit back under the back of the cover.... Have fun guys.
 

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The light output from your rope light looks great! You don't need all the wiring to fit inside, you just need to seek it so water can't get inside and ruin your nice, new lights.

Good luck, throw up some pics of the assembly once it is together.
 
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