UrS4 /A6 headlight conversion

[UrS4Eben]

Hi guys as some of you UrS4 drivers will know, our headlights in standard form has a very finite life before the reflector starts melting and make a mess inside the headlight units.
It has happened to both mine now and after some searching on here and advice, I decided to retrofit to, supposedly better engineered A6 units.

First of all lets look at the differences:
1. S4 unit has 2 sockets at the back whereas the A6 only has one with more pins
2. The Design of the glass lens is different with the A6 unit having a more slanted angled part. The S4 glass will fit on the A6 housing but the A6 glass will foul with the S4 reflector if you try and swap it that way.
3. The rubber surround is different.
4. Newer design lever motor but seems to use the same plug.

Here is a comparison between the two units with the S4 on top and the A6 on the bottom

Here is the glass S4 on the top and A6 below

This is the A6 unit from the back before work started. Notice only 1 connection for the lights as opposed to 2 for an S4 unit.

Here I carefully drilled the hole in the stock S4 location to swap over the connector

Disconnected the leads to the bulbs and cut the ground and park light leads with a little left

This is the A6 connector that is not being used again

Back of the A6 unit with the S4 connectors retrofitted and wiring redone.

Of course I also swapped the S4 glass and rubber and also made sure not to touch the reflective surfaces and get all the drillings out with a hoover without damaging anything.

One left to go now then I'll fit them to see if there is any problems. I'll update the topic in case anything interesting comes up

PS let me know if anyone is in need of individual parts from the leftovers.

Also I plan to convert to HID at some stage which should fix the heat issue once and for all.

[UrS4Eben]

Just fitted the first one during lunchbreak..
Works perfectly. Only other mod needed is the breaking off of a thin piece of plastic so that the indicator housing can lock on to the headlight housing.

one down one to go .....

[andrewd]

That's a great write-up! Thanks!

The headlights on my S4 are holding up okay, but it's great to know there's an alternative to scouring the scrap yards for S4 items if and when they do start melting.

How do they look fitted? Is the curve of the A6 item very visible through the S4 lense?

[quattro20v]

I also made an extra hole to the back of the plastic, for letting the heat out. I made it to the cover that you take out when you change the bulbs. No moisture has come to the glass.

How do they look fitted? Is the curve of the A6 item very visible through the S4 lense

There is no difference to the original, becouse you will put the old glass back to the new plastic housing.

How much was the hella parts?

[UrS4Eben]

Thanks Andrew.
The shape of the silver part looks exactly the same when you look from the front its only if you look from the top that you see an indentation made because of the different shaped A6 glass but as you will see you cannot spot the difference.

quattro: I didn't buy the parts from hella. I bought 2 complete A6 units from Ebay for £30 each all I used from the S4 units is the glass, rubbers and electricla plugs.

Tested them tonight and they look NICE

As I said before if anyone needs A6 shaped rubber gasket, glass or internal parts from the S4 units let me know cos I dont want to throw them away.

[S2central.net]

Looks like they grew there... Nice upgrade !

[UrS4Eben]

Thanks S2

Just drove about 1500 miles on the longweekend and I reckon this mod, even with standard bulbs, provide better illumination than the original S4 units....

[quattro20v]

I also recommend to add relays to the lights. More power and it will save the light swicht not to burn. Just need to mod the autocheck not to alarm of the front lights.

Just measure the voltage from the bulbs, mine is now 14,28v

[UrS4Eben]

OK a little update:
I bought this HID(6000K) kit: http://cgi.ebay.com/ebaymotors/HID-C...spagenameZWDVW
£38 shipped.
Very good communication from seller, goods sent with tracking code and is sent as gift.

I installed them today. A kid could do it. Drill a hole just big enough for bulb and grommit. install lamp wire up using existing connectors, close up, place and plug in ballast and bob's your uncle... No Autocheck either.
Here is some before (1st one one halogen, one HID and second both HID)
Only unknown is how long it will last but things are looking good and quality seems fantastic for the price.