CorvetteForum - Chevrolet Corvette Forum Discussion

CorvetteForum - Chevrolet Corvette Forum Discussion (https://www.corvetteforum.com/forums/)
-   C4 Tech/Performance (https://www.corvetteforum.com/forums/c4-tech-performance-48/)
-   -   adding a 3rd brake light on a 85 (https://www.corvetteforum.com/forums/c4-tech-performance/2580472-adding-a-3rd-brake-light-on-a-85-a.html)

RJblk85vette 04-24-2010 05:34 PM

adding a 3rd brake light on a 85
 
I have a 85 that I am wanting to add the 3rd brake light. I already have the housing, what I am trying to figure out now is what wires do I tap into, so far the only way I can get it to light up is if I am on the yellow and black or green and black. Problem with that is, when the turn signal is on the 3rd brake light blinks. Anyone know what wires to tap into? Thanks

c4cruiser 04-24-2010 05:49 PM

The 3rd brake light on the 86 and later cars had it's own wire that went to the brake light switch. Later switches had a different connector to accommodate the wire and connector. You will probably have to run a dedicated wire from the existing switch back to the light.

Cruisinfanatic 04-24-2010 05:59 PM


Originally Posted by RJblk85vette (Post 1573865626)
I have a 85 that I am wanting to add the 3rd brake light.

Why would you want to do that?

slickfx3 04-24-2010 06:12 PM

the think it looks great and it is after all 3rd light

HlhnEast 04-25-2010 11:43 AM


Originally Posted by c4cruiser (Post 1573865753)
The 3rd brake light on the 86 and later cars had it's own wire that went to the brake light switch. Later switches had a different connector to accommodate the wire and connector. You will probably have to run a dedicated wire from the existing switch back to the light.

:iagree: I think the idea is in case something happens to your other brake circuit, this one still works. Well that and to have an additional brake light at eye level that hopefully someone will see befor they smash into you. Unfortunately even on the coupe this light aint any higher than most normal brake lights.

I have an '85 too and I will eventually add the third light I got with a trade vette. I will run a dedicated wire to it.

surfer92 04-25-2010 12:36 PM


Originally Posted by slickfx3 (Post 1573865938)
the think it looks great and it is after all 3rd light

WHAT????????? :toetap:


Definitly a safety feature I want, been nailed 3 times in the rear, in the 1st 3 years I owned the car.

856SPEED 04-25-2010 01:59 PM


Originally Posted by slickfx3 (Post 1573865938)
the think it looks great and it is after all 3rd light

:crazy:

what did you "try" to say??

856SPEED 04-25-2010 02:05 PM


Originally Posted by HlhnEast (Post 1573871914)
:iagree: I think the idea is in case something happens to your other brake circuit, this one still works. Well that and to have an additional brake light at eye level that hopefully someone will see befor they smash into you. Unfortunately even on the coupe this light aint any higher than most normal brake lights.

I have an '85 too and I will eventually add the third light I got with a trade vette. I will run a dedicated wire to it.

To each his own......what are the chances both tailights go out and you get rear ended because no one knows you are applying your brakes? might as well add air bags and anti lock brakes too....get it safe.....:willy:

slickfx3 04-25-2010 02:50 PM


Originally Posted by 856SPEED (Post 1573873179)
:crazy:

what did you "try" to say??

I think the 3rd light looks better on the car than without....

and the bonus is the followers can see you better


understand?

LD85 04-25-2010 02:55 PM


Originally Posted by Cruisinfanatic (Post 1573865824)
Why would you want to do that?

:iagree: http://ingunowners.com/forums/images/smilies/dunno.gif

rons85 04-25-2010 05:20 PM

Beyond running a wire to it you also have the problem of actually Mounting the '86 and newer lamp housing onto the '84-85 hatch. The bolting for the housing will interfere with the hatch glass, which was cut out/contoured to clear the 3rd brake light when it was added to the cars in 1986.

It was done to My '85 by the PO (or he had it done..), and done poorly by basically epoxy-ing studs onto the housing further forward than they should be so that they could go into holes drilled into the hatch hinge plate and miss the glass. Poor answer, one which I ultimately had to fix by flame cutting a mounting plate and thereby getting something a bit better.

The "right" answer, of course, would be to change out the hatch for an '86 or newer..

383vett 04-25-2010 10:56 PM


Originally Posted by rons85 (Post 1573875010)
Beyond running a wire to it you also have the problem of actually Mounting the '86 and newer lamp housing onto the '84-85 hatch. The bolting for the housing will interfere with the hatch glass, which was cut out/contoured to clear the 3rd brake light when it was added to the cars in 1986.

It was done to My '85 by the PO (or he had it done..), and done poorly by basically epoxy-ing studs onto the housing further forward than they should be so that they could go into holes drilled into the hatch hinge plate and miss the glass. Poor answer, one which I ultimately had to fix by flame cutting a mounting plate and thereby getting something a bit better.

The "right" answer, of course, would be to change out the hatch for an '86 or newer..

Absolutely wrong. The hatch is the same for an 84 and 85 as it is for an 86 on. I added a third brake light years ago on my 84 and it fit perfectly. Just have to measure and drill carefully, 2 holes for the studs and one for the wires. I did use a module that used to be available so that the light wouldn't blink when the signal lights were turned on. Kragens had it at the time. I'm not sure if it is still available.
I removed mine a couple of years ago when I changed to a different rear bumper but still used the module for the in bumper mounted 3rd brake light.

http://i539.photobucket.com/albums/f...o/5-28-08d.jpg

HlhnEast 04-25-2010 11:18 PM

383, I think folks would have a hard time catching you, much less actually getting close enough to hit ya!! :lol: Did you tap into the wiring at the back of the car? You shouldnt have a problem with it if its a dedicated line.

I have seen plenty of cars that the third light was the only thing working and it saved em from having my GMC truck impaled in their azz. Remember I live in Bama, no vehicle inspections here and honestly the third light is enough legally, only one required here. :rolleyes:

rons85 04-26-2010 05:12 AM


The hatch is the same for an 84 and 85 as it is for an 86 on. I added a third brake light years ago on my 84 and it fit perfectly.
Then whoever did the install on mine botched it completely. I don't see how it could work, however - the stock stud location on the brake lamp didn't look to Me like it would allow the assembly to be mounted far enough back to allow the hatch to open, not unless the holes were drilled through the glass.

Apparently the installer had the same thought, which is why he cut the stock studs off and used epoxy to attach them differently. Which worked, for a couple of years at least.

Or Something.. All I know for sure is that I had to futz around with the thing to cobble up a better solution, one which Still isn't "stock", but works.

RJblk85vette 04-26-2010 08:34 AM


Originally Posted by rons85 (Post 1573875010)
Beyond running a wire to it you also have the problem of actually Mounting the '86 and newer lamp housing onto the '84-85 hatch. The bolting for the housing will interfere with the hatch glass, which was cut out/contoured to clear the 3rd brake light when it was added to the cars in 1986.

It was done to My '85 by the PO (or he had it done..), and done poorly by basically epoxy-ing studs onto the housing further forward than they should be so that they could go into holes drilled into the hatch hinge plate and miss the glass. Poor answer, one which I ultimately had to fix by flame cutting a mounting plate and thereby getting something a bit better.

The "right" answer, of course, would be to change out the hatch for an '86 or newer..

I am not using the roof mounted stop lamp. I have one that came off a 95 that went in the rear bumper. I have the newer style rear bumper so IMO it looks goofy with out having the brake light there. I am not sure if I am going to do that now. I dont know if I want to cut the bumper, after all its a fiberglass one.

AGENT 86 04-26-2010 09:10 AM


Originally Posted by c4cruiser (Post 1573865753)
You will probably have to run a dedicated wire from the existing switch back to the light.

:iagree:

383vett 04-26-2010 10:10 AM


Originally Posted by HlhnEast (Post 1573878900)
383, I think folks would have a hard time catching you, much less actually getting close enough to hit ya!! :lol: Did you tap into the wiring at the back of the car? You shouldnt have a problem with it if its a dedicated line.

I have seen plenty of cars that the third light was the only thing working and it saved em from having my GMC truck impaled in their azz. Remember I live in Bama, no vehicle inspections here and honestly the third light is enough legally, only one required here. :rolleyes:

The module allowed tapping into both brake light wires in the back and eliminated blinking when the turn signals were applied. A dedicated wire from the brake switch would also work.

little98dime 04-26-2010 09:26 PM

I installed one on my 85. I ended up routing from the brake switch to the rear of the car. the main problem you will run into, is the glass on the rear hatch overlaps where the mounting holes need to be drilled. because of this, you have to attach 2 bolts (i used high strength epoxy) roughly 1" back from the original mounting holes. this way, you can drill through the hatch, missing the glass entirely. I can post pics if needed.

RJblk85vette 04-27-2010 02:09 AM

thanks for all of the input. I still cant decide if it is going to be worth all of the trouble...lol I have one of each of the 3rd brake light housings, one for the roof and one for the bumper. I have never been a fan of the looks of the one on the roof so IF I do add it I will use the one that goes in the bumper. Thanks again

Hot Rod Roy 04-29-2010 02:16 AM

There's already a wire in your harness for the third brake light, that comes directly from the brake light switch. This wire is light blue, and goes to the connector for the rear body wiring, pin B of a 15 pin connector. There is no wire at pin B in the rear body wiring harness. I think this connector is located below the right side rear compartment courtesy light.

This wire was used for European 'vette's that had amber rear turn signals and dedicated brake lights, rather than the dual purpose brake/turn USA style lights.

:flag:


All times are GMT -4. The time now is 12:21 PM.


© 2024 MH Sub I, LLC dba Internet Brands