'97 high-mount brake light "rebuild"

'97 high-mount brake light "rebuild" FINALLY DONE!

EDIT: Adding the details to the first post now that the project is finished.

OK, I finally got tired of trying to figure out this stupid 21" neon high-mount brake light problem, and in the process ended up with two lamp assemblies. So, after searching for the best fix, I finally decided to gut one of the assemblies, and build by own LED array to put inside it. Here is what I did ....

• After removing the assembly from the truck, and the lamp from the assembly, I baked the lamp in the oven at about 200-250 for 15-20 minutes, or just long enough to be able to "peal" off the lens. After doing that, removing the neon lamp, and cleaning it up, here is what I had.

• Here is the assembly after being baked, and cleaned up, and the neon lamp removed, with some measurements shown:

• Next, I had to find some LEDs. I finally found some that would work and purchased them from Super Bright LEDs:

http://www.superbrightleds.com/​

• I ended up settling on the 8 candella RED (RL5-R8030), but after seeing it all done, I'd probably go with the 12 candella if I did it again (RL5-R12008), as they are brighter, and have a sharper viewing angle. You can always tone down the brightness if it is too bright, and although I could brighten mine up a bit, it would mean less protection for the LEDs.

• Next I found a piece of breadboard to mount the LEDs to. You can probably find something at Radio Shack, but you might have to make a two piece array, depending on the size you get, and how long you actually want your array to be. Notice in the image above that the assembly is about 3/4" tall, but since the back of the housing is curved, the array needs to be thinner than that so that it can fit comfortably down inside, so the lens does not hit the LEDs.

• I cut the breadboard so that it would fit inside the housing. When doing this, measure carefully so that the breadboard will fit down inside the housing, otherwise the LEDs will touch the lens and you'll have trouble putting it back together. Learn from me - I had to do a lot of fine tuning to get everything assembled.

• After determining how many LEDs I wanted, and how far apart they should be, I placed the leads through the breadboard and glued them in place. Be sure they are pushed down all the way, and are flat, or your LEDs won't line up perfectly, which is easy to see with these small viewing angle LEDs.

• Next, I soldered the LEDs and resistors to make the arrays. I have 3 arrays of 5 LEDs each. You can use this link to help determine the resistor size needed for each array:

http://led.linear1.org/led.wiz​

• Here is the LED array in progress. This was the dry run, before cutting the breadboard and glueing the LEDs.

• After cutting, glueing, soldering, and wiring up the array, I was ready for the fine tuning, and fitting into the housing. Sorry, I forgot to take a picture of that, but you get the idea.

• I searched high and low for just the right glue to use, but in the end I just used hot glue on the array, and clear RTV to glue the array into the housing, seal any extra holes (I brought both wires out a single hole), and glue the lens back on. I also used electrical tape to hold stuff together while it was drying. I did it in stages and let everything fully dry before I put the lens back on.

• Here is a BAD picture of the array finished, and everything dry fit.

• And finally, with everything glued and dry, I took the plug off the old ballast and used that on the new LED array. Make sure you feed the wires through the hole in the tailgate before placing the plug on the wires (I had to go back and cut mine off again )

• After reinstalling on my truck, here is what it looks like.

I hope this helps. Let me know if there are any questions.

 

[rizzjc]

That's pretty weird. Would love to know the technical reason behind that. Not that I doubt you. I had completely disconnected the other lights though, and verified 12 volts going to the balast, and the lamp still didn't work. Figuring out if it was the balast or the lamp was going to cost to much either way, so I took care of it for good. Glad you got yours working easily.

 

[YellowEdge4x4]

Thank-You for all your work RIZZJC. My inspection guy let me slide on the brake light because he knew I would fix it. Went to the dealer today to get a ballast ($150). Hooked it up and the light still didn't work. Went back inside, returned the ballast and bought the light ($245). Got home and it didn't work either. After lots of testing with a voltmeter it started working. New light, old light, doesn't matter. New light goes back Monday. Did you get a final measurement on the width of the bread board? I was looking at the 9 bulb bread boards at SuperBright. They are .5" x 4.5". Do you think 3 or 4 of those would fit?

 

[rizzjc]

The boards at superbright are too wide I think. And they told me they are "not rated for marker lights" whatever that means. I would recommend just getting your own perf board (Radio Shack or somewhere), cut it down, and mount a pile of the brightest LEDs they've got. Amazing how much the lens diffusses the light.

I've heard others claim that a "minor" short somewhere in the wiring harness for the taillights/trailer harness, can cause the 3rd brake lamp not to work. I disconnected the whole harness and it made no difference, so I went this route.

 

[N182NS]

Thanks for your info on the third brake light. I used the P/N K-69-01-C2 from J.C. Whitney $14.99 and took the leds and put them in the housing. They fit
perfect. To make it look really good use two or three of them. They are 6 inches long. Beats $400. Nick

 

[rizzjc]

Good deal! I might look at that. I've thought about making another one sometime (I still have a housing) with more LEDs in it than I have now. Once you put the lens over it there is no fear of it being TOO bright.

 

[YellowEdge4x4]

I bought 4 of the "Universal LED PCB" boards and 36 LEDs (RL5-R12008) from SuperBright. Put them together with 330 ohm resistors. They were a perfect fit inside the housing. No cutting/trimming necessary.

 

[1996xlt]

Would something like this work?: http://cgi.ebay.com/2p-12-w-30pcs-P...4QQihZ020QQcategoryZ26207QQrdZ1QQcmdZViewItem

 

[rizzjc]

Looks like it would, but you'd have to know how thick it is (i.e. top to bottom, so it'll fit inside the housing). Also, you would probably want to know what type of LED. If it is a really wide vewing angle, and low mcd, then you won't be able to see it very well once the lens is on top of it. But definitely let us know. Always easier to buy something pre-build. I couldn't find anything like that when I did it.

 

[makena]

OK, I tested my old ballast and found 0VDC output, moved the probes on the meter a lot and still got 0VDC, so bought a replacement ballast from an online junkyard. Installed it, light worked, and I was happy.

2 days later it was off again. I thought perhaps there is something wrong with my lamp and it is blowing ballasts. Next day went to take apart and light was working again.

Now I find it works intermittently. I don't get why.
I want to get access to where the wires come out of the lamp unit and see if there is a short.

But to do this I have to drill rivets out? That seems pretty extreme. There is no way to get access to pull the lamp unit out without drilling out the rivets?

And if you don't replace them, then what holds the whole thing in place?

 

[rizzjc]

You have to remove the rivets to REMOVE the lamp, but you might be able to get to the wire. I'm confused though - if you got to the ballast output, then you got to the wires going to the lamp. As for the rivets, there are also two studs and snap nuts on the ends. I've had my rivets out for over a year, and nothing has gone anywhere. The window glass does rub on it when you open and close, and that causes the corners of the metal trim to tear slightly, but not other problems.

 

[makena]

Thanks for the reply. Yes I can see the part of the wires behind the ballast but can't see beyond the hole. I can reach with my finger and feel where the wire must go into the light but can't see it. I'm looking for perhaps some insulation worn off the wire? Maybe I'm grasping at straws.

I'm going to try something else next. Put a rod or broom or something on the brake pedal so it is on all the time, then go back and try moving the wires and see if I can get the light to go on and off, to try to figure out which wire it is or where the connect/disconnect is happening. The connectors are tight, I don't think it is them. Yesterday it was working, then stopped. I opened the tailgate and just hit the trim where the ballast is with my fist, then went and pressed the brake and it started working again.

I guess the other possibility is that the replacement ballast I got from the junkyard online is flaky. Pretty bad luck to have that happen so soon after another similar problem in the same area.

 

[rizzjc]

If you pull the rubber plug on the other side, you might be able to pull the wires out more. I can't remember exactly. Not much in there to short them out, but anything is possible. It's a '96, just take the drill to it!

 

[chuck_gardner]

I bought 4 of the "Universal LED PCB" boards and 36 LEDs (RL5-R12008) from SuperBright. Put them together with 330 ohm resistors. They were a perfect fit inside the housing. No cutting/trimming necessary.

Had the same problem on my 1995 Explorer and found this thread with a search. It was a huge help in diagnosing the problem and getting the thing apart. What the heck was Ford thinking when they designed this thing?

Tube looks OK but Ballast out measured 0V. Dealer wanted $160 for the replacement ballast. I've ordered the PCB and LEDs recommended above and am currently looking for the resistors.

As I understand it there are 9 LEDs per board and three resistors. Does that mean three LEDs are wired in series per resistor on the board?

How do you determine the value for the resistor should be 330 ohm?

Chuck Gardner
Manassas, VA

 

[rizzjc]

Depends on the specs of your LEDs. I think I calculated mine for 13.8V DC.

Check this link from the first post:
http://led.linear1.org/led.wiz

You can calculate for different scenarios of LEDs. I think I did 3 banks of 5 LEDs, if I recall correctly. You could do it differently, and different LEDs would have different values. I would recommend getting the absolute brightest, most direct beam you can find in a 12V LED. The lens really takes a lot away from it. I wish mine were brighter, but it does the job.

 

[YellowEdge4x4]

Yes, 3 LEDs are wired in series on those boards. I got my LED info from teh page rizzjc mentioned and this page http://www.cardomain.com/ride/296394/13. The LEDs I bought are bright enough. The lens definately makes a bigger difference than you would think.

Wish I had taken a picture for you, but I didn't. Connect the boards together end to end. I used the ends I cut off the resistors after they were soldered in place. Make sure you watch the polarity on the boards, + to +, - to -. Pay attention to the polarity of the LEDs when you solder them in also. If you turn one around that series of 3 won't work. Connect 2 wires to one end of the strip. I used Clear RTV to hold the LED strip in the housing, then sealed the lens on with more RTV.

 

[chuck_gardner]

Thanks for the replies...

Thanks for the replies. Aside the 101 experiment breadboard kit I had in the 6th grade I really haven't messed around with building circuits but do keep a soldering iron handy for the odd repair and should be able to muddle thorough this project and get the beast through inspection.

Chuck Gardner

Yes, 3 LEDs are wired in series on those boards. I got my LED info from teh page rizzjc mentioned and this page http://www.cardomain.com/ride/296394/13. The LEDs I bought are bright enough. The lens definately makes a bigger difference than you would think.

Wish I had taken a picture for you, but I didn't. Connect the boards together end to end. I used the ends I cut off the resistors after they were soldered in place. Make sure you watch the polarity on the boards, + to +, - to -. Pay attention to the polarity of the LEDs when you solder them in also. If you turn one around that series of 3 won't work. Connect 2 wires to one end of the strip. I used Clear RTV to hold the LED strip in the housing, then sealed the lens on with more RTV.

 

[rizzjc]

A $5 third brake lamp from Harbor Freight, stuck to the inside window will get you through inspection. That's what I did. Then had time for the bigger project.

 

[chuck_gardner]

Finished....

I got the LEDs and boards in the mail today and in a couple of hours managed to get it all put together. When getting the resistors at RatShack I also picked up a clamp stand with magnifier for the soldering which simplified the task. The four boards linked together were a perfect fit inside the silver reflector.

Thanks again for posting this idea...

Chuck Gardner

 

[rizzjc]

:ttiwwp:

OK, this THREAD has pics, but I'd still love to see the finished results from other people.

 

[MYIBRAHIM]

Small Change

I did like your ideia but i got lead strip from http://stores.ebay.com/KIML-LED-Lighting-Company

$1.45 + $5.00 s&h and i used zip tie to tie it to the neon bulbs and vowala it works very good