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Discussion Starter #1
I've been searching for a while for the best way to illuminate the rear reflectors on my 2014 Volt. I have ruined 3 reflectors trying to take them apart and add LED strips. It is not only very difficult to do, but it doesn't match the brightness of the OEM tail lights very well.

So, I eventually found what I think is the easiest and best-matching way to get tail/brake lights to the reflectors.

You don't have to take the reflectors apart. Just remove them from the car and drill a 7/8" hole into the middle of the back of the lens, in the middle of the three little holes that are in the back side of the reflector. You are essentially making that middle hole into a 7/8" hole. The only tricky part is setting up the hole saw so that the pilot bit is just barely (1/8" or less) sticking out beyond the saw. Then drill through the back slowly, check where you are, and then keep drilling through the red lens, but no further. Take your time check where you are frequently. The hole saw goes through the plastic very easily, so no real force is needed. When you are done, chip away the edges of the holes, especially the red lens hole, with a little screw driver or a probe, to clean up the cut. Then take a vacuum and hold it to the hole while you shake the reflector around. This gets all the chips out. You can see any chips you missed through the front of the lens. Keep shaking and vacuuming until there are no bits left in the lens.

The light to use is Phillips 3157 LED. It is a very bright red LED stop/tail light. It needs to be modified for our purpose. What you do is cut of the top round section of the bulb. It doesn't do anything, it's just a hunk of plastic. Cut it off flush as close to the little notch as possible (see photo). Then sand it smooth, apply a blob of RTV to the flat surface, and stick the bulb into the hole you made in the reflector. Align the bulb so that the base is vertical, up and down, NOT horizontal. The LEDs are at an angle in this bulb, and shine down onto the reflective surface inside the reflector, which is what makes the light look so close to OEM. There will be a gap between the bulb and the hole, which I covered with reflective aluminum tape.

You will also have to drill a 7/8" hole through the hatch where each reflector mounts. Again, easy to do, but make a template of your modified reflector so you get the hole in exactly the right place.

The 3157 has separate running light / brake light, both 12V, so it is easy to wire. Use a 12V source to identify the 4 pins on the bulb base. 2 of them are marked +, so the other two are grounds - touch the +12V to each of the 2 + pins and you will find which is the brake and which is the tail light. Mark the brake light + with a sharpie or something. The grounds don't matter - they will be connected together anyway. You could buy a 3157 bulb socket for ease of wiring, but I just soldered my wires directly to the bulb pins.

Install the reflectors back on the car.

Now connect the 2 brake lights from the reflectors together and the 2 tail light wires together, and run a single brake light wire and the single tail light wire to the plug in the left side trunk compartment. Ground the wires from the bulb grounds at the hatch latch plug connector black wire.

There are lots of threads here about how to run the wiring and where the brake light and tail light wire connections are, so I won't go into those details.

Some photos of the result:







[video]https://i.imgur.com/06W2c6U.mp4[/video]

Best Regards,

e
 

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I've always felt they should be illuminated. Sounds like you found a relatively easy way to do it. Any chance we can get some pics in darker conditions to see how it would look while driving? Is the lighting fairly even across the reflector surface?
 

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yeah you are gonna have to post a multitude of pics to back up what you did but mostly some night time pics with running lights, brake lights and signal lights illuminated so we can see how they really look. daytime pics do absolutely nothing for the mod.
 

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Very cool!

I noticed that when the brake is not depressed, there appears to be some pulsing or varying intensity in the outer (normally lit) light. I'm guessing that bulb is lit with pulse-width-modulation .... ? And there's a slight sync difference between the pulsing and the camera?
 

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NICE WORK! I totally want to do this with the side reflectors as well.
Do you have photos or a template of your modified reflector so I get the hole in exactly the right place?
Thank you
 

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Any chance we can get some pics in darker conditions to see how it would look while driving? Is the lighting fairly even across the reflector surface?
+1

(SUBSCRIBED)

I remember a bazillion years ago a neon letter on the front of the movie theatre where I worked was replaced. It looked good until night when you could see it was definitely not as bright as the other 5 letters.
 

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Makes sense, better the posterior drill then "cooking" the reflectors... Can we have a PIC of the final product in the dark ?. I do not like to see the individual led lights like a Xmas tree...LOL
 

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Interesting idea, but we need pictures of the process.
 

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That is a nice mod. I stumbled across a guy on YouTube that has this and sells it as a kit you bolt on, no drilling. He has a good video of the whole install and how it looks at night. A possible alternative for those who want an easier route, although more expensive, too. I don't have the link, but I assume it is easy to find.

I personally am not into appearance mods. Why go to all that trouble to please the person stuck behind me in traffic? Not something I worry about, and they probably don't care, either.
 

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Would love photos of the process and of the connectors before I rip into my Volt.
Is it possible the side reflectors are the same and could do the same mod?
Any idea what the center bar connections are?
 

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Thanks!

Parts ordered and I already have an appt on Tues for other work on my Volt. Going to see if they can squeeze this in as well.

I'm hoping the relay wiring isn't needed since it's just a couple more LED's. We'll see what the installer thinks.
 

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Discussion Starter #14
You don't need a relay. The the bulb has 2 leads - one for brake light and one for tail lights. So you just need to run one wire to the brake light and one wire to the running lights.

It really bothers me that the prototype Volt had these illuminated, but the production cars don't. Also. much more visible at night.

I will post more photos of the process and the results soon.

Best Regards,

e
 

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Discussion Starter #15
Yeah. Well, there's already a bunch of holes through the hatch behind the reflectors, probably where the wires would go on the OEM illuminated reflectors, if they had been included. One more doesn't hurt anything, and you'll never see it. By the way, the metal is ultra-thin and easy to cut through. You will drill through two layers of metal.

Best Regards,

e
 

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Discussion Starter #16 (Edited)
Here are some more images. Cut off the top of the Phillips 3157 bulb and sand or file smooth. You want to see the LED connectors on the top, but DON'T sand through them, or the bulb won't work. Stop sanding when you can see all of the connectors, as in the photo; they are encased in clear epoxy, so you will see them long before you sand through them. (These are NOT LEDs, they are copper strips that connect the two banks of LEDs together. If you sand completely through them only one bank of LEDs will work. Ask me how I know.)

Also you can see how I marked the Brake light pin and soldered wires directly to the pins of the bulb.

The yellow arrow shows where to drill the 7/8" hole with a hole saw - center it with the middle of the three holes in the back of the reflector. Notice how the hole goes through the back of the reflector, the red transparent part, and does not go any further.

The modified bulb is glued with RTV solidly into the hole, flush with the front surface, and aligned vertically. I marked the brake light pin in red so I can hook it up correctly. The white tape on either side of the bulb is reflective aluminum on the other side, so it helps with directing the light into the reflector. I also covered the exposed wires with clear RTV so there wouldn't be any unintended shorts - and surrounded the bulb with RTV where it sticks out of the hole, so it is very secure. The bulb is good for tens of thousands of hours, but if it needs to be replaced it comes out pretty easily, and you can install a new bulb and solder the wires and re-RTV it.

The video shows the lights at night. They look pretty good, IMO.







[video]https://i.imgur.com/gIcgBZI.mp4[/video]

Best Regards,

e
 

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Thanks, those pictures will help. Do you have some showing how you routed the wires from the reflector to the brake and running light splice?
 

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Discussion Starter #18 (Edited)
Anthony Vigil has an entire series on YouTube on how to install the rear reflectors, including how to remove the trim, and where to find the brake/tail connector. He also sells kits for the modification. You have to take the trim off of the hatch, which is pretty straightforward and easy, and find the connector inside the left (driver's side) compartment in the trunk.

This connector has several wires, the ones you want are the yellow wire, which is the brake, and the thicker white wire w/ yellow stripe, which are the running lights. Use Posi-Tap connectors - they are easy and work every time, and you don't have to cut the wires to tap into them. Don't use Scotch-Lok taps - they don't work 50% of the time. For my method, you do not need diodes or a relay, just wiring. A drawing is below.



Best Regards,

e
 

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The link after the pics in post 16 shows a night video. Looks good, Just wish there was a longer demonstration of the brake brightness. Toward the end of the video the lights do increase in brightness, in what appears to be caused by a door lock/unlock command being sent but the flashes are a bit too quick to really get the full effect.
 
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