How To: Adding a third taillight, the easy 'n cheap way!

[Shep]

I looked at all the other tutorials posted here for third tailights, and everyone seems to make the entire procedure way too complicated. They mention things like adding relays and fuses, removing trim pieces, getting behind the seats, connecting new wires to the battery, all kinds of very involved work, even though DeLoreans already have built-in brake lights! Strangely, it seemed no one had simply tapped into this preexisting function without reinventing the wheel. So I decided to do it myself, and took plenty of pictures along the way. I spent less than $25 on the entire process, including the cost of the third taillight, and it takes less than an hour once you have all the parts handy. Unfortunately, it is much too long to post here (I couldn't get below the 5,000 character limit without removing important information), so I have posted it on my website.

Total cost: < $25 (your mileage may vary)
Total time: 30 to 60 minutes (plus acquiring parts)

[Link to tutorial]

Questions and comments are welcome!

[Nicholas R]

How does the wire run from the light off of the louvers? Is it glued? Taped?

This is what I'm curious about:

[Shep]

How does the wire run from the light off of the louvers? Is it glued? Taped?

If you mean the third taillight itself, it's stuck on with outdoor rated velcro. If you mean the wire itself, it's held on by a binder clip as seen in Step 14, where it freely hangs over the edge as seen in Step 23, where it then hangs on another binder clip attached to the bottom of the strut support and runs down the C-pilliar as seen in Step 15 (click the first image for full size -- easier to see zoomed in). It's not hidden or anything, but at some point I plan on redoing the wiring so it's a bit more hidden. When I do, I'll probably route it straight forward, into the slotted vents at the top of the rear window, across to the left, then down the C-pillar.

[Nicholas R]

Oh I thought the binder clips were just to hold it during install. I'd want something more secure and aesthetically pleasing than that. The wiring is actually one of the biggest reasons I do not like 3rd brake lights. No matter what it just never looks right to me. Still, if anything I recommend getting some adhesive backed cable time mounts that you can hook the to the underside of the louver you're actually mounted to and ditch the binder clips all together. If you ever want to remove the brake light you can just cut the zip tie leaving the mount in place, then replace the zip tie when you put it back.
Something like this:


I actually used these on my frame to hold my starter wires out of the way of my headers with my old engine. They work really well!

[SS Spoiler]

For your information it is possible to feed wires through the upper SS fold at the top of the rear pontoon window.

Paul Cerny
37lb. SS spoiler

[Shep]

Oh I thought the binder clips were just to hold it during install. I'd want something more secure and aesthetically pleasing than that. The wiring is actually one of the biggest reasons I do not like 3rd brake lights. No matter what it just never looks right to me. Still, if anything I recommend getting some adhesive backed cable time mounts that you can hook the to the underside of the louver you're actually mounted to and ditch the binder clips all together. If you ever want to remove the brake light you can just cut the zip tie leaving the mount in place, then replace the zip tie when you put it back.
Something like this:
[image]
I actually used these on my frame to hold my starter wires out of the way of my headers with my old engine. They work really well!

Should have clarified better: the binder clips are temporary, but I haven't replaced them as of yet. Still need to find a suitable plug for easy rear fascia removal. The third brake light comes with a plug built in to allow for easy replacement/removal (also why I used Velcro), but it's somewhat difficult to take the plug from there and work it all the way down to the rear fascia where I routed it.

If those come in smaller sizes, I'll probably use a few for the C-pillar. Thanks for the suggestion!

For your information it is possible to feed wires through the upper SS fold at the top of the rear pontoon window.

Is this the part you're talking about? (#24 on the 8-3-0 diagram here.) If so, I was toying around with that idea for when I rewire it at some point to add the rear fascia removal plug. I wasn't sure if there was anything there I should be concerned about, so it's good to know it'll work. Thanks!

[SS Spoiler]

If you run your wires to the passenger side of the car by the upper louver hinge you can feed wires through the SS fold above the side pontoon window. This will get you close to the wiring for the brake lights. Do yourself a favor and put some disconnects to enable removal of the louver.

[Shep]

If you run your wires to the passenger side of the car by the upper louver hinge you can feed wires through the SS fold above the side pontoon window. This will get you close to the wiring for the brake lights. Do yourself a favor and put some disconnects to enable removal of the louver.

Thanks for the tip! This should work for someone reading my tutorial, but unfortunately it won't work for me for two reasons: 1) my passenger side window has a crapton of residential window putty around it, and it's practically impossible to work around that, and 2) the wire is already attached (and zip-tied) to the driver's side wiring, so I would need to do a lot of extra work to reverse that. I did notice however that when the wires are black, they're basically unnoticeable when they're wedged between the pontoon and the rear quarterpanel. You can see them if you're trying to find it, but if done right, it honestly looks like some sort of molding, unnoticeable even to a DeLorean fanatic. When I get to rewiring everything, I'll have to grab some black shrink-wrap and figure out how to keep the wire there.

EDIT: one other note: the reason I put the binder clip at the frontward part of the second louver is because when the louvers are open, it's hidden by the topmost louver. The only part of the wiring you can see is the part on the C-pillar when everything's being "shown off", but going a bit forward into the rear screen upper finisher, to the side, then bordering the rear quarterpanel hides it there too.

[EdR5150]

Nice work on the 3rd light. That's a lot like the one I made, no complicated electronics: http://www.16908.info/?p=1161

[Shep]

Nice work on the 3rd light. That's a lot like the one I made, no complicated electronics: http://www.16908.info/?p=1161

Indeed, it does look similar! I had a feeling someone else had done it this way before considering it's been 30 years since they started (and ended) production, and this was an idea that came to me within weeks of buying it that I got done before I even had it for one month. Now I see what SS Spoiler was talking about when he mentioned the stainless steel fold. Might be worth switching the routing to the passenger side if there's no such fold on the driver's side.

Good note on the rear screen upper finisher being too small for the plug. I'll have to find a wide and flat plug that'll fit through the slots. Also a good note on why an inline fuse is perhaps a better idea than I originally thought. Never thought about how a short would render the brake lights useless. Probably a good investment compared to the repair bill for getting rear ended.