LED Tail Lights, home made

[Avanti83]

Thanks to a number of members in previous posts that put me on a track to construct a bright set of LED tail lights.

A couple of thoughts first. I used my old housings but needed to modify then by cutting a slot in one side to accommodate the LED panel. I did a quickie measurement  initially and thought the panels would fit but they were about 1/8" to large and there was no way to file them smaller without getting into the circuits. I'll start with the finished picture as it shows the completed assembly and the parts needed to create same.

I ordered extra 1157 panels to add to my backup lights also. Total cost is under $50.

The bulbs are 1157 Red LED panels from Superbrightleds.com. They were being closed out at less than $3/bulb. Because I have rewired the entire car I wasn't interested in using the bulb base so I removed it. I used the red panels with a 15 degree light angle for the build.

An important point. When you remove the wires from the base it leaves a resistor behind in the plug. The resistor is necessary to reduce the brightness of the tail light portion. I tried to reuse the ones in the base but no joy. They turned out to be about 150 Ohm resistors so bought 20 of them off Ebay for $4. There was room for two panels in each housing so I used clear Gorilla glue to join two panels.

Cut a piece of 1/8" ABS sheet to cover the slot in the housing, grooved it to accept the panel and Gorilla glued it in.

This is the housing modified and painted white.

If you look below you can see I attached the LED panel assembly with clear silicone and a couple of screws. To exit the light assembly I added a bulb socket stripped of it's internals to hold the wires in place with silicone and also added a three wire Weather pack connector to connect directly into my new wiring harness.

Here's a Youtube video of the assembly powered up with a 12 volt battery.

 

[wildfelr]

RQB3263....81 Avanti ...yes very good job...BILL

[WayneC]

Very nice writeup, thanks!

But... which variety of 1157 panel did you choose? Those panels are in the process of being discontinued, so only red 15 degree panels are now available.

Edited January 3, 2018 by WayneC

[Avanti83]

Interesting. When I ordered mine there were 15 and, I think, 100 deg panels. I ordered the 15 deg to maximize the light behind the tail lights as there isn't much exposed from the side of the light and the panels are pretty deep in the housing. IAC, I'm very happy with the brightness.

 

[WayneC]

Just out of curiosity, did you use white or red LED's?

And, how do the LED's go from normal tail light brightness to brake light brightness... a normal stoplight 1157 has 2 filaments, I think (so do only half the LEDs illuminate for tail light and then all for brake light? or is it solely the resistor that accomplishes that by somehow making the LED's glow brighter? Is the current switched to go through the resistor with the stop lights vs no resistor with normal tail light... or what?)

 

This might be a simple yet viable choice:

 

Edited February 9, 2019 by WayneC
replaced photo with lower resolution version to get sme of my posting space back

[Avanti83]

Wayne, the resister is installed on the tail light bulbs to reduce the light output. The full voltage (no resistor) is applied for turn and brake lights. The panel is wired so both tail and brake light wires are in the same spot. The full voltage for turn and brake just drives the same lights brighter.

I used red because IIRC a red lens only passes red light so any other color would not be as bright as other wave lengths of light except the red wavelengths would be filtered out.

I ordered amber 1157 LED bulbs for the front parking lights for the same reason, amber lenses.

Edited January 4, 2018 by Avanti83

[WayneC]

Thanks. Too bad SuperBrightLEDs.com has discontinued the 1156/1157 panels.

I was looking in eBay listings and noticed a number of LED panels configured for internal car lighting, which may lend themselves to tail light applications, except that (1) they are white LED's and (2) they would need to have 1156/1157 bases added (but I'm not certain that would work with LED's that aren't meant to be tail lights, nor do I know what resistance value needs to be added to dim them)

Edited January 5, 2018 by WayneC

[Avanti83]

Wayne

Here are the adapters https://www.amazon.com/Adapters-Sockets-Covert-Wiring-Socket/dp/B007FUF32S

And the resistance is 150 ohms if they are auto brightness panels.

White should work but they may not be as bright as a total red panel. For the price these things go for I'd give it a try. The OEM Avanti lights aren't that bright to start with so it shouldn't be hard to improve on them.

I'll bet some of the panels you are looking at may be brighter than necessary. IDR what my panels were rated for in lumens but I think they were under 100. Just check on the super bright site and search based on those numbers for a start.

Good luck, Bob

[WayneC]

Appreciate the link, Bob....  I assume you also need to add a 150 ohm resistor to change brightness on a panel? Also, how did you address the blinker issue where LED's don't have enough resistance to activate the stock blinker unit?

My interest is mostly academic, hopefully gleaning info for others who read your post... I converted my '71 backup lights to LED tail lights about 8 years back (using LED 1157 bulbs and sockets, and I may have added a resistor for the blinker... not certain because I think I retained the normal 1157 bulbs in the tail lights).

I wasn't satisfied with my conversion, particularly the klutzy wiring, and would like to have even brighter lighting. The backside of the decklid has an unfinished look that I never figured out how to cover. It may be possible to run the wiring through the raised ribbing of the decklid to make things neater.

 

Edited January 5, 2018 by WayneC

[Avanti83]

Wayne

I'll be purchasing the red lenses and adding the same LED panels I used in the tail lights to the backup lights for additional brake and tail lights. 

The 150 OHM resistor is added in the tail light feed line to reduce the voltage so they are not as bright as the turn/brake lights. The LED 1157 bulbs are wired the same way internally.

You can see the 150 OHM resistor in the complete assembly shot in the blue feed line in my post and the current must pass through it.

To use the lights with a standard flasher (non LED) I used a 30 OHM resister added between the brake feed line and the ground line. Think parallel wiring. I added them to all the lights on my 54K. They work fine but what a pain in the arse.

This is the LED flasher I'm using on the Avanti. It works with just one LED light so it should be fine for the car. https://www.ebay.com/itm/LED-No-Load-Electronic-Flasher-12-VOLT-2-WIRE-With-Polarity-Reversing-Adapter/152833558628?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649 Be sure to get the one with the ground wire. Similar ones without the ground wire didn't work in my applications.

Using the LED panel should solve the exposed wiring issue you  have shown, if necessary.

As far as losing the backup lights, I'd rather have the back of the Avanti glow like an amusement park after dark.

Bob

 

Edited January 7, 2018 by Avanti83

[studegary]

Many states have a requirement for working back-up (reversing) lights after a certain year of car.  Small back-up lights could be added below the bumper or next to the license plate.

[wildfelr]

RQB3263  81 AVANTI II ...I have the material and can make you  red lenses for almost nothing ...call me 386-466-6434 if you havent all ready bought them ....bill

[Avanti83]

Bill

Missed you last year but I now have your number in my phone. I'll call you in February and come up and see you. I'll take you up on your offer of the red lenses.

Bob

Edited January 12, 2018 by Avanti83