[glhs#116]

This is just a short writeup of what I did to rectify the differences between what classic American car lighting is and what is legally required in the UK for my 1971 Trans Am. This is the short version:

In front:
US classic
amber lights are solid as "daylight running lights" and flash as indicators

UK requirement
white lights for daylight running lights
amber flashing indicators

In rear:
US classic
red tail lights that go bright red as brake lights and flash bright red as indicators

UK requirement
red tail lights that go bright red as brake lights
amber indicators
brake and indicators can't interfere with each other's function
also required is separate bright red "fog" lamps that can be set on with an illuminated switch from the drivers seat


So, for the front part I was pretty pleased to find that you can buy these 1157 LED bulbs that are "switchback LEDs" that are white when on "dim" mode and amber when on "bright" mode. Since my Trans Am has clear front indicator lenses (relying on an amber bulb) the only thing I needed for the front to conform is a pair of these switchback white/amber LEDs.

Oh yeah. You'll also need to stick in some resistors or the flash will be too rapid. The flasher callibrates of the bulb resistance. I put in "LED flasher" units and it still didn't work right until I added the resistors.

The back is more of a challenge. Last time on my old Shelby I went the easy route and just hung extra trailer lights off the rear bumper. But I really didn't want to hack the TA and I definitely didn't want extra lights hanging off or too much wiring butchery.

So, all my challenges are at the back of the car.

My first problem is the need for amber turn signals that aren't brake lights and red brake lights that aren't turn indicators all whilst keeping the original cluster. And my first breakthrough finding was that single colour LEDs have very strong light colour. An amber LED behind an old GM red lens still shines amber! So red/amber switchback LEDs will give me amber indicators but still red taillights. Since I have four taillights I decided the outers should be indicators and the inners should be brake.

The next challenge is wiring (which I'm allergic to by nature anyway). I really wanted to resist much change to the wiring and certainly preferred something clean and reversible. What I decided to do was leave the tail light harness as it was but attach two new bulb holders for the new "brake only" lights. There is an orange and white set of wires going to the brake pedal switch. The orange is power and the white is signal (powered when the pedal is down). I opted to cut this and add weatherpack connectors to it so that it could be reconnected if desired. I then added a new wire from here to the back and ran it into the "high" wire on the two new holders. The "low" and ground wires on the holders I just teed into the existing harness wires for "lights on" and "ground".

Here's the wiring changes. The blue wire is the new one.

This is where I tapped into the brake switch up front


Here's the lefthand new socket with the blue wire coming in for brake and then going over to the other side. The low bulb and earth are teed from the original socket


And here's the righthand side doing pretty much the same

[glhs#116]

So, here's what it all looks like now.

Lights on normally


Lights on with indicators


Brakes on with indicators


Brakes on lights off


Now, what are the problems with this setup? Long term, I'll have to wait and see. I'm still waiting to be able to get the car legally on the road so I haven't been able to actually drive anywhere. But by far the biggest issue is that these are "gimmick" LED bulbs. That means you can't buy them from anyone reputable, only no-name Chinese companies. As such there are probably potential safety and long-term durability concerns. But one of the biggest practical concerns even if everything works as it should is that being "gimmick" bulbs they are far too bright in the normal "dim" mode. The photos don't do a good job of showing this but a normal signal/brake/tail bulb is MUCH brighter when on "high" than "low". It's 21watt versus 5watt. So over four times the power when you hit the brake or indicator. The LEDs are pretty bright on "high" but they are also far too bright on "low". This means that my tail lights may be annoying and that the brake lights may be less obvious when my lights are already on. That's one of the things I expect I will find out by driving.

There's still one bit missing. I need to add some rear "fog" lights (bright red lights) at the rear. For this I plan to install a switch and fuse and another wire. I'm going to take the reverse lamp sockets and replace them with dual filament type. Then I'm going to install red/white switchback LEDs. The white will get the normal reverse light signal. The "high" (red) will go to the new switch. This way my reverse lights can be my fog lamps (you never need both functions at the same time). For this it actually works out well that these bulbs are equally bright in both modes..

Don't know if anyone else has attempted something like this but I'd love to hear of any different approaches.

Sam

[OG68]

I did something similar to this many years ago when I had to fix my brake lights on an old Mercury after getting a CHP fixit ticket.

I used the back up lights as turn signals by cutting the brake/signal wire at the tail lights and then splicing each signal wire into the back up light sockets using a single filament amber bulb.
I then ran a single wire direct from the brake light switch and spliced it into the previously cut wires at the tail lights. Passed CHP inspection

A few years ago I had a 72 VW Beetle that I added Hella Fog lights to. Hella sells a rear fog light that bolts to the rear bumper bracket. Brighter than the brake lights.
Utilized the factory rear defogger switch and relay which not only let me splice into the disconnected wiring going to the rear window but also gave me a dash light indication.

[Geoff]

Sam,

I think you have been misinformed about LED lights. Good quality LEDs are much more reliable than conventional tungsten filament lamps, which eventually fatigue & fail.

Also, not all LED lamps are Chinese. I bought LED lamps from superbrightleds.com in the US for my GTO. They had different brightness levels available & different colours. Very pleased with them.

[glhs#116]

Geoff,

Nah, read my message again. I have a lovely pair of Sylvania red 1157 tail lamp bulbs that act just like an incandescent and I have no doubt would work well in every situation for years. But companies like Sylvania and GE with real engineers that meet real regulations about how the bulbs should work don’t make the “switchback” LEDs necessary for this all to work.

You will note that my two brake lights don’t need switchback bulbs because the requirement there is red/red. I still couldn’t use the Sylvania bulbs there because they go much dimmer on low filament than on high, like a real incandescent bulb, and it would have looked odd next to the two red/amber switchback bulbs that don’t. So I still had to use no name red bulbs there for it to look consistent.

I have seen brighter tail lights on some newer cars. I guess I will just have to see if it looks weird and/or anyone stops me.

When it is finally back on the road that is.

To be clear, this whole project is not about “going LED” because of something great about LEDs. It’s about trying to meet the UK legal lighting requirements without cutting up the car or hanging extra lights.

Sam

[Stuart]

One other thing about UK light requirements is the low beam headlights need to have the correct light pattern for driving on the other side of the road from the US.

[Mickey_London]

What I have on my Firebird is :-
Both inside and outside rear are side lights and brakes when braking. Would rather people see when I am braking :-)
The reversing lights are now indicators, so I have no reversing lights
I do not have any fogs lights
Mick

If your car is built or registered after April 1980 then it needs Fog Lights for a MOT

[glhs#116]

Originally Posted by Stuart

One other thing about UK light requirements is the low beam headlights need to have the correct light pattern for driving on the other side of the road from the US.

Fortunately I have some Hella H4 conversion headlamps which are DOT spec. The UK spec would kick up at the left. The Euro spec would kick up at the right. The DOT spec has pretty much a flat cutoff. It doesn't illuminate the hedgerow as nicely but there's also no need to change it if I drive abroad. It should pass UK spec.

Sam

[glhs#116]

Originally Posted by Mickey_London

What I have on my Firebird is :-
Both inside and outside rear are side lights and brakes when braking. Would rather people see when I am braking :-)
The reversing lights are now indicators, so I have no reversing lights
I do not have any fogs lights
Mick

If your car is built or registered after April 1980 then it needs Fog Lights for a MOT

I also don't like giving up two of the four brake lamps. But I like the idea of having just about all the correct lighting functions in what looks like the correct places. I thought about just leaving the flashing red indicators in back but I'd also not like to give the excuse in an accident that the other driver didn't know I was indicating...

This is pretty much all for my satisfaction and amusement, really. As the car is 1971 it is (or will be when I eventually get my logbook) registered as historic. So no MOT to pass. It also means that when I do finally get it registered I can run those sweet sweet black and silver plates..

Sam

[Mickey_London]

I was toying with the idea of having the lights as original as possible, ie side lights and separate brake lights, but then when I see the brakes light all lit up I had an Epiphany haha
Mick
Where in the UK are you, I am in Kent

[glhs#116]

I am up in Country Durham. A bit far from you. How long did it take to get yours registered? I have been at this since April. Are you on the POC-UK Facebook page?

San

[Mickey_London]

I bought mine 3 years ago up near you. Newton Aycliffe.
Mine is a 1970 and been in the UK since 1971 so it was already registered. I don't have a Facebook account
Mick

[glhs#116]

Originally Posted by Mickey_London

I bought mine 3 years ago up near you. Newton Aycliffe.
Mine is a 1970 and been in the UK since 1971 so it was already registered. I don't have a Facebook account
Mick

You, sir, are a wise man. But I found that POC-UK’s forum has pretty much died the death and the only responses you can get are on the Facebook page. May it never happen here!

I would love to see your car some day.

Sam

[Mickey_London]

If you ever venture down this way, you will be more than welcome
Mick