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Texas Twister
01-10-2014, 09:47 AM
Many on the early D's had the brake light wire kluged in at the factory with an inline fuse because there was an error in the wiring harness. The dead wire is just hanging there. Does anyone know where this wire goes? It would be nice to connect it to the fuse box and get rid of the inline fuse.

Dracula
01-10-2014, 03:43 PM
I'm not sure how the wiring works or when the cut-off was before they changed it, but there's an easy way to tell if your car has the early setup. With the car off and the key out of the ignition, apply the brakes. If your rear lights come on, then you have the early wiring setup where the brake lights are connected directly to the battery and use the switch as the only intermediary.

The only particular advantage to this setup is that, if you want to install a 3rd brake light (not something I ever plan to do, as I don't like the looks of the darn things) that you have a direct battery connection via the brake switch and you won't see a voltage drop with the addition of a non-LED bulb, as in the later variant.

Bitsyncmaster
01-10-2014, 04:13 PM
Many on the early D's had the brake light wire kluged in at the factory with an inline fuse because there was an error in the wiring harness. The dead wire is just hanging there. Does anyone know where this wire goes? It would be nice to connect it to the fuse box and get rid of the inline fuse.

I think mine (has the inline fuse) did not have that wire in the fuse area. I wondered if it was just a missing wire in the early harness. I don't recall seeing any extra wires when I did my new fuse block.

Texas Twister
01-10-2014, 04:25 PM
What I'm trying to find out is where does the dead wire by the brake light switch (green) go? Dracula, I am using about 12" of edge light red LEDs on either side of the center spine on the rear louver. It is virtually invisible when unlit. I have also added a brake light strobe that flashes 4 times fast, 4 slow then solid on. The module is attached to the right taillight circuit board and wired in using 4-40 screws and nuts. There are no unreversible connections. I have noticed they pay a little more attention now.

Greasy DeLorean Mechanic
01-10-2014, 07:08 PM
#2508 is still torn all to pieces, so I should be able to trace that wire out for you after the rain ends.

Bill Robertson
#5939

Bitsyncmaster
01-10-2014, 07:32 PM
What I'm trying to find out is where does the dead wire by the brake light switch (green) go? Dracula, I am using about 12" of edge light red LEDs on either side of the center spine on the rear louver. It is virtually invisible when unlit. I have also added a brake light strobe that flashes 4 times fast, 4 slow then solid on. The module is attached to the right taillight circuit board and wired in using 4-40 screws and nuts. There are no unreversible connections. I have noticed they pay a little more attention now.

Ah....the extra green wire at the brake switch. I do remember that but never investigated what it was for.

Dracula
01-10-2014, 07:33 PM
I have nothing against third brake lights; I just don't care to add one to my car. It's a matter of personal taste, I suppose, just like how I don't care for the side stripe, either.

Greasy DeLorean Mechanic
01-12-2014, 05:16 PM
#2508's brake light wiring:

- Green wire from Fuse #1, ganged with another Green wire into a female quick connect hanging loose next to the brake pedal switch (can't tell if it passes through the Green junction on the drivers side of the console or the Green junction on the passenger side of the console because both junctions have continuity between them while soldered together. Note that there is also a Green junction under the dashboard -- didn't try ringing it out).

- Green wire scotch locked onto Brown/Red, next to a steering column harness connector, from the main power bulkhead connection next to the coil. Green wire passes through an inline glass fuse, then to the brake pedal switch.

- Green/Purple from the brake pedal switch to the Black bulkhead connector.

Nothing in Fuse #18 position in the fuse box.

Bill Robertson
#5939

Boglin
01-12-2014, 09:35 PM
Third brake light will definitely be something i add soon. Does anyone sell a kit?

Dracula
01-13-2014, 03:46 AM
I find it amusing that those who most loudly profess the advantages of the 3rd brake light; going so far as to say that the cars are "unsafe without them" and that it's "something all owners MUST do and would be MAD to ignore" drive their cars less in a year than I drive mine to work in a given summer week.

BABIS
01-13-2014, 08:09 AM
Third brake light will definitely be something i add soon. Does anyone sell a kit?

yes DPNW http://www.delorean-parts.com/Merchant2/merchant.mvc?Screen=PROD&Store_Code=DPNW&Product_Code=K3002DP-A&Category_Code=9450

Texas Twister
01-13-2014, 08:48 AM
Bill,
I'm confused, the green wire with the female connector on it that you mention, you indicate it is tied in with the other greens, so fuses 1, 3, 4 or 5, so it should be hot when the ignition is on. Mine is never hot.
Dracula, to each his own. I don't like the big third stop lights either that's why I waited till I found the edge mount LEDs. My car is a daily driver with over 200k on it. I notice that when people are tailgating to take a picture they slow a little quicker when I hit the brakes. I like that. It's hard to prove a negative. Of course I know

Texas Twister
01-13-2014, 08:56 AM
People that still don't believe in seat belts either. Enough said.

I bought my parts from Superbright LEDs. The module was three or four bucks, the LED strips are actually close in price to those at Autozone. I did get some connectors that let me unplug the lights at the louver and at the tail light. If anyone is interested I can take some pictures and make a parts list.

Greasy DeLorean Mechanic
01-13-2014, 10:55 AM
Bill,
I'm confused...

Apologies -- I wasn't thinking clearly (must have been that football game -- now I know how Saints fans must feel). As long as there are light bulbs and other resistive devices in place, circuits will of course ring continuity between themselves. You'd have to pull all the devices out to isolate wiring between them. Fuse #1 was just the first fuse I tested -- never even tried #3-#5 (some/all of them should have rung out as well).

Looking at the wiring diagram and comparing it to the car:

The Green junction right next to the central HVAC plenum appears to be the Green junction pictured below the fuel gauge on the wiring diagram (fed by Fuse #5). On closer inspection neither of the Green wires ganged into my loose quick connect takes off from that junction.

Green junction at the back of the driver's side of the console is the Green junction pictured above the fuel pump on the wiring diagram (takes off from Fuse #1). None of the wires in/out of that junction continue forward in the car -- 3 of them return to the relay compartment and 2 go to the ECU compartment.

There is one Green wire going up the driver's side of the console that takes off from Fuse #3. If the wiring diagram is correct, this is the windshield wiper motor.

3 Green wires go up the passenger side of the console: 2 from the Green junction at the rear of the passenger side of the console, and 1 from Fuse #4. Again, if the wiring diagram is correct, the lone wire from Fuse #4 should be turn signals (via the hazard switch -- nuance of DeLorean wiring: remove the hazard switch and you lose turn signals too). Process of elimination would make the Green junction at the rear of the passenger side of the console the junction pictured below Fuse #5 on the wiring diagram, albeit with 2 wires going to the front of the car rather than just one....

So, I'm still not sure where the two ganged wires in my loose quick connect come from/go to. They are bundled with Green/Purple, so they would appear to be part of some discarded brake light circuitry. They ring out to all the Green fuses, they definitely aren't cut off inside the harness (there are other wires here & there that are...).

Hope that helps. Fuse #18 slot in #2508 is empty, so if your car is similar you could simply wire it up and run your own power supply for the brake lights. I use it to power the dash switch in my modified headlight circuit (from the factory the headlight switch internal illumination bulb is not protected).

Bill Robertson
#5939

Greasy DeLorean Mechanic
01-13-2014, 11:23 AM
Just did some more poking: Green wire into the hazard switch does not come from the passenger side console harness, but runs over from the driver side footwell.

There are 5 wires in the rejoined harness bundle in the driver footwell. Four of these come from the back of the car:
- Windshield wipers (direct from Fuse #3)
- Two wires from the rear passenger side console junction (fed by Fuse #5), apparently instrument cluster
- Turn signals (direct from Fuse #4)

5th Green wire in the driver footwell does not come from the back of the car. It appears the loose quick connect with two Green wires next to the brake light switch is also a junction: wire in from Fuse #4, wire out to the hazard switch. Perhaps after lunch I will cut it off to make sure (hazard switch should then be dead).

Bill Robertson
#5939

Texas Twister
01-13-2014, 11:25 AM
Bill,
Thanks for the investigation.

Greasy DeLorean Mechanic
01-13-2014, 11:34 AM
Oh what the hell -- why not hack up your wiring harness on a beautiful sunny morning:

Loose quick connect definitely feeds the hazard switch. Just cut it off and my switch now is dead.

All Green wiring to the front of the car can be accounted for. There are only 4 Green wires in/out of the junction next to the central HVAC plenum, so the second Green wire running up the passenger side of the console from the junction at the rear (Fuse #5) feeds something pictured under the instrument cluster on the wiring diagram, most likely the Lambda counter.

I'll make a Green only diagram later tonight.

Bill Robertson
#5939

Farrar
01-13-2014, 03:26 PM
The "dead" green wire by the brake switch is definitely "hot when key on" in my car. I connected it to my headlight switch's illumination wire so that the button is lit even when the lights aren't on. (It's an LED so the added power draw is negligible.) #2613 has some characteristics of "early VIN" vehicles, but not others. Your mileage may vary...

Texas Twister
01-13-2014, 05:00 PM
My error, you guys are correct, it is hot with the key on. Thanks.

Greasy DeLorean Mechanic
01-13-2014, 05:18 PM
The "dead" green wire by the brake switch is definitely "hot when key on" in my car.

Whose dead are you referring to: mine or Ian's? My wires were never dead -- it was the hazard switch that died when I cut the quick connect off. I'm 99.9997% certain that one wire into that quick connect comes straight from Fuse #4, and the other one definitely continues to the hazard switch because I rang it out while loose.

Bill Robertson
#5939

Farrar
01-13-2014, 05:41 PM
Whose dead are you referring to: mine or Ian's?

This one:


The dead wire is just hanging there.

Greasy DeLorean Mechanic
01-13-2014, 05:49 PM
There are only two reasons I can think of for DMC to have made the scotch lock/inline fuse mod (take that everyone who poo poos scotch locks and inline fuses -- DMC did it at the factory):

1) So brake lights work even with the key off
2) To reduce amperage load through Fuse #4

1) seems much more likely than 2).

Bill Robertson
#5939

Bitsyncmaster
01-13-2014, 07:58 PM
There are only two reasons I can think of for DMC to have made the scotch lock/inline fuse mod (take that everyone who poo poos scotch locks and inline fuses -- DMC did it at the factory):

1) So brake lights work even with the key off
2) To reduce amperage load through Fuse #4

1) seems much more likely than 2).

Bill Robertson
#5939

Those four 25 watt bulbs are quite a load. Think your guess is correct.