A4 Coding for A3 Sportback Rear Lights

aristides

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Hello there fellas.

A friend of mine is trying to code his Tail Lights to make them look like the old A4 Lights

I searched through this forum and couldn`t find anything usefull

What I mean?
The Tail Lights in an A4 use both outer lights + the fog lights dimmed at about 24 (?) % when the running lights are on, and when the brakes are applied the outer unit glows at 100%, while the fog lamps still remain at 24%

I hope you get what i mean :)

Is this possible?
I have seen it for sure from a German bloke!

Cheers
 
Urrm I think I was discussing this with 1wheelonly the other day, could be different thing but worth a try, try setting it to 0% & see what happens.

If this works then cant take credit for overall as was him who advised me about this on the phone, but I'll take thanks for the memory kicking in today, lol
 
As i can see the US Cars got this coding as standard, but nobody in Europe has a clue about how it can be done!

N. which one should i set to 0%?

Got this from openbd.org

Byte 07 Extra Function: Turn Signal Front left/right as Parking Light Front left/right (USA and Canada)
Byte 08 Extra Function: Low Beam left/right as Daytime Running Light - Scandinavia (Standard: 0%)
Byte 09 Extra Function: Brake Light left/right Rear as Parking Light (Standard: 18%)
Byte 10 Extra Function: Rear Fog Light left/right as Parking Light (Standard: 12%)
Byte 11 Extra Function: Front Parking Light left/right (Standard: 0%)
Byte 12 Extra Function: Rear Parking Light left/right (Standard: 0%)
Byte 13 Replacement Function: Front Side Turn Signal left/right as Front Parking Light (Standard: 0%)
Byte 14 Replacement Function: Front Parking Light left/right as Side Turn Signals left/right (Standard: 0%)
Byte 15 Replacement Function: Rear Light left/right as Side Turn Signals left/right (Standard: 0%)
Byte 16 Replacement Function: Front Fog Lights left/right as Low Beam Headlight left/right (Standard: 0%)
 
Can you be more specific in your original post as to how the old A4 works so we can give correct info & I know exactly what you're trying to achieve overall mate please, then maybe can be more specific to what can try, also just try each individual one & remember original setting then test & change back if doesnt help.
 
Well good point, i didn`t explain it that good

Lets see...
Each side of the Sportback has 2 Tail lights. The outer part (2 bulbs included) and the inner part -fogs- (1 bulb)
I want all 3 of them (on each side) to work at 24% with the running lights on, and when the brakes are applied to work at 100%

I guess you know how the old coding works?
if not, then you should know that with running lights work only the outer tail lights (2+2 bulbs to be exact) at 24%, and when the brakes are ON they glow 100%.

The fogs work only when they are selected from the inner light switch.
 
If im understanding right I did what your asking on my sportback a few years ago.
This is copied form a post I made on VWvortex a few years ago about coding the lights.
Dandle said:
OOOO-A3 said:
Can you give me some taillight information in return?


See the picture below. Not counting the backup lights and turn signals, the A3 has three bulbs as labeled 1, 2, and 3 in the picture.


I'd like to know how these are configured by default on European A3s.


Position 1:
Tail light only?
Brake light only?
Both tail and brake (tail gets brighter for brake)?

Position 2:
Tail light only?
Brake light only?
Both tail and brake (tail gets brighter for brake)?

Position 3:
Rear fog only?
Tail + rear fog?
Brake + rear fog?
Tail + brake + rear fog?

On the American models:
- all three are on as tail lights
- all three get brighter for brake lights
- '3' can also get brighter for rear fog (left, or left+right) only with a Euro switch and programming, but is not set up that way from the dealer.

Thanks.

light-positions.jpg

Sorry to drag such an old thread back up. Im really trying to find out how to get the inner lights on the tail gate working(they are just fogs at the moment). Both 1 and 2 come on as tail lights and position 1 also work as brake lights. I would like to know how to code the lights so all three work as tail lights with 1&2 being brake lights and making position 3 tail and fog lights. Ive searched everywhere(even asked Ross-tech) and cant find an answer but I know that American cars have position 3 as tails so it must be possible.

Thanks for any help.


And heres the reply.
OOOO-A3 said:
Your complete answer can be found here: http://oooo-a3.blogspot.com/20....html

The short answer is in Central Electronics, set Byte 10 to '18'

Hope that helps.
 
You`re the boss mate

Awesome, thanks 10000 times!

Will try it and tell you the results!
 
Hmmmmm...

I just received my European (LHD) spec headlight switch this weekend, and when I plugged it in, I had the VAG-COM ready to start digging in to the coding.

However, the ****** thing just worked perfectly from plugging it in (this is a US-Spec 20008 model with an 11/07 build date) WITHOUT any reprogramming. -I understand that most US-spec A3's were NOT like this, but certainly I can confirm that at least SOME (mine included) were delivered from the dealer already coded that way.

What I get is 1, 2 & 3 all on dimly (~5-Watt) as tail lights, all three go to full (21-Watt) power when the brakes are applied. When the rear-fogs are turned on, number 3 goes full-brightness, but 1 & 2 remain unchanged.

I believe that under UK law governing 'rear lights for low visibility situations' or however it's legally termed, rear fogs must NOT be used for any other purpose (such as brake-light 'reinforcement', or tail-light 'reinforcement').

I know that I read the regulations a year or two ago and they were quite clear about that; it's now a question of whether any policeman who happens to be behind you is as well-read!

(if I can find the relevant section, I'll post a link.)

Keith
 
Νο worries Keith, i found a PDF including everything that i needed thanks to Dandle

Now I know what each byte does in long coding, so i can start making some tests!

Thanks!!!
 
Thats whats good about forums, sorted now then mate?
 
Yeah!

I got a great PDF telling me everything that i need :)

If anyone needs it pm me!

Thanks all for the help
 
Good stuff matey.

-Actually I just noticed that you were in Greece, so that stuff I mentioned earlier about UK lighting regulations plainly doesn't apply to you... -Sorry! (I'd just assumed you were in Britain).

But since I was thinking about it, it did get me to realise... the American coding would in fact be completely illegal in the British Isles.

Here's the link to the VOSA regulations:
http://www.opsi.gov.uk/si/si1989/Uksi_19891796_en_16.htm#nsch11

wherein it states:
No rear fog lamp shall be fitted to any vehicle so that it can be illuminated by the application of any braking system on the vehicle
Personally, I don't see any incontrovertible reason for prohibiting using the fogs as a "double-up" brakelight when not in use as a fog light, but apparently the same prohibition is NOT in effect in the US. While we don't really get much fog in my particular area at all, we DO get torrential downpours where you can't see the car in front through the spray. -In these circumstances, having rear fogs makes a noticeable difference between being seen and not being seen. I have NO idea why they're not required in the US.

Keith