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Strange tail light wiring

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rlandrum

rlandrum

Jedi Trainee
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I'm rewiring the lights to the rear of the TR3A, and I noticed that the wiring harness seems to indicate that the turn signal lights were the "outside" lights, while the "inside" lights were used for brake lights.

This conflicts with what I see in the wiring diagram. The inside lights are for the turn signals, and the outside lights were for the brake lights.

Is my wiring diagram correct? Or should I rewire exactly as it was?

Also, how were these lights grounded. I've got grounding leads soldered onto all of my tail lights, but I don't know if they were each grounded seperately or if there was 1 master ground run to all of them. Nothing is left of the original grounds for me to examine.
 
It might be overkill but during my entire car rewire I could not get all the rear bulbs to function. Finally
I soldered a seperate ground wire to each bulb. I then
installed grounding blocks on either side of the rear
trunk sides and ran the ground wires into the 2 blocks.

Then I connected the two blocks with another ground wire.
Finally I ran a ground wire from the rear grounding block
on the driver's side back up front thru the firewall to
the engine block.

After that, all my rear lights finally function.

Every light bulb in my TR6 now has a seperate ground wire going to a grounding block.

On my TR6- brake lights are red, turns are yellow and reverse are white. Running side lights are yellow.
 
And Dale, you neglected to show him your rear lights
that you fashioned while awaiting proper parts to come.
Do you remember that post and those pics?
I think it would be appropriate to revisit that one
more time right here.
 
It's been a long time since I owned a TR3, but on mine, the outer lights were the brake lights, and the bulbs were grounded through the receptacles, with no external ground needed.
However, age takes its toll, and external grounds may now be the way to go, if you dont want to take the time to make sure that the receptacles have an acceptable ground to the body.
Jeff
 
Bugeye58 said:
the bulbs were grounded through the receptacles, with no external ground needed.
However, age takes its toll, and external grounds may now be the way to goJeff
Click to expand...

Jeff exactly the problem with my car. Loose fitting bulb holders.

Heres one of my front lights ground bar. Also a photo of
after market designer tail lights for the 1969 TR6.

grounds.jpg


AMOS2-1.jpg
 
rlandrum said:
I'm rewiring the lights to the rear of the TR3A, and I noticed that the wiring harness seems to indicate that the turn signal lights were the "outside" lights, while the "inside" lights were used for brake lights....Is my wiring diagram correct?...
Click to expand...
Correct? Yes...and no. The TR2 and TR3 models had turn signals on the "outboard" lights and a single, center-mounted, combination brake/license plate lamp. That's apparently what your wiring diagram shows. Late TR3s and all TR3A and TR3B models had stop/tail lamps (L549) outboard, flasher lamps (L594) inboard, and a license-plate-only lamp (L467) in the middle.

Hopefully Randall will be along soon to elaborate, but I believe there are some late editions of the Owner's Handbook with a correct wiring diagram for the later cars. Meanwhile, you might find this diagram from Dan Masters to be of some help.
 
Ah... So whoever did the original restoration on this car replaced the wiring harness with one designed for a TR2 or TR3, rather than the TR3A. I wonder if there's anything else out of the ordinary with this car.

I ran ground wires to the receptacles because I wasn't confident that the receptacles would ground sufficiently. I suspect however that that is how they were originally grounded.

I think I'll run a wire for each to a grounding block which I'll locate in the trunk.
 
There were actually quite a few different wiring diagrams; I don't have all of them yet. But if you'll PM me your email addy, I'll send along one that should be pretty close for your 59 (depending on your exact commission number). It's even been somewhat doctored for LHD connections (although the gauges are still shown in the wrong places, as original).

Andy is right (as usual) about the correct light configuration for your car ... although some people have opted to add more brake light filaments either by using the stop/license lamp assembly from an earlier TR2-3 or by using dual filament fixtures for the turn lamps.

The original grounds were through the receptacles, sheet metal screws and J-nuts. Far from secure, IMO, especially where the nuts slip over the body sheet metal. I made up a harness to daisy-chain all 5 lamps, and run around the floor of the trunk to one of the gas tank holddown bolts.
 
I just drilled a small hole near the rear, and put a stainless steel screw through it. Everything seems to work, except I think I have a short running from the green-purple at the rear to the front somewhere.

If I try to light the brake lights (by touching a negative battery lead to the bullet connector) from the the right side, only the right side lights up. If I do it on the left, both light up, but the right is dimmer than the left, even though it's connected to the high intensity side of the bulb.

The wiring diagram I've been working from has been pretty good, up until this weirdness on the rear lights. I think I may need to pick up a new marker light, since I have two different styles; one with two leads (i.e. brake and marker) and one with one lead (i.e. just marker).
 
I had the same problem but my right side was dimmer.
The problem was faulty grounds. I tore out everything, rewired with individual ground wires and ground blocks with a ground wire running to the engine block.

No more dim lights after that.



d
 
Andrew Mace said:
...Odds are the previous owner mixed up the lamp bases front and rear...
Click to expand...

Or had to source a replacement back in the day when junkyards were still the place to go for parts, and just got a front one instead of rear.

I picked up a set of the double-filament to convert the 2 tuen signal lights to also be auxilliary brake lights. Hard to imagine having too much brake light. If oyu want to to this you're already half way there.
 
Geo Hahn said:
I picked up a set of the double-filament to convert the 2 tuen signal lights to also be auxilliary brake lights. Hard to imagine having too much brake light. ...
Click to expand...
I realize this might have been discussed before, but exactly how do you plan to wire these lights? i.e. which filament ends up being which? Seems to me that a combination brake/flasher lamp is going to be a bit too much of a compromise, as one or the other will then have to be on the weaker of the two filaments?
 
What I did was to make the brake filament be the weaker; so the turn signals could still be seen with the brakes on. Yes, that leaves the brakes rather dimmer than I would like, but since the original bright filaments are still there (and I also used amber lenses for the turn signals), I still felt it was better than the original setup.

Another option would be to use relays to make a single filament do double-duty as brake/turn (as many American cars do). I think you can buy the setup pre-packaged as a "5-wire to 4-wire converter" for trailers but I've not looked into any details.
https://www.discountmarinesupplies.com/Tr..._CONVERTER.html
 
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