Lighting Upgrades


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Upgrades & Enhancements

Lighting Upgrades

Euro Lights
Auxiliary Lights & High Wattage Bulbs
9004 to 9007 Conversion
Rewiring Headlights w/Relays
Fooling the Autocheck system after Rewiring
Fog Lights
Fog Lights on w/o Headlights
Rear Fog on w/o Front Fogs
Turn Signal Lenses


Let's face it -- Audis sold in the U.S. have crappy lights. The DOT has some pretty stupid rules concerning bulbs and reflectors and lenses, and it seems that VAG decided to give us the worst headlights that the DOT would allow. It's ironic that such a safe car was fitted with these completely useless lamps. The car is a menace to drive at night.

Euro Light Upgrade
The best solution seems to be an upgrade to European lights. They have a MUCH better pattern and look completely OEM. The image at left is a comparison of the low beam pattern of the Euro-lights (left) and the original DOT crap (right). I sort of raided the game on this one, because my Euros have 80W lows, and those DOTs probably had the standard 55W bulbs. That's OK, though, because you can still see the benefit of the Euros over the DOTs -- the pattern.

The Euros have a sharp horizontal cutoff that keeps light directed down at the road rather than up in other drivers' eyes. You can also see how the cutoff of each light angles upward to the right. This throws light onto the side of the road, making it much easier to see street signs, pedestrians, etc. By contrast, the DOT lights cast a poorly defined blob of light in front of the car, with much of it concentrated in a small area, rather than spread evenly across the entire road. Also notice the amount of light on the ground directly in front of the car with Euros, compared to the DOT car. I've found that my fog lights are almost totally redundant now.

There are two options for drop-in euro lights for this car. Both Hella and Bosch (possibly Cibie, too) are OEM for these lights. I give the Hella part numbers just because I have them. Some vendors will only have Bosch available, which is fine. Even though they are different brands, the parts are virtually identical. In fact, things like replacement lenses are compatible between them.

Eddie Dalgado at Wolfsport (800-342-8669) sold me a pair of the H4 lights for $350, which is about what you'll pay in Europe. Wolfsport will even buy back your old DOT lamps -- you ship the lights to them, they examine their condition and make you an offer. If you decline, they ship 'em back to you. You can also get a good price on the Euro lights from Metrix in Canada (800-4-METRIX). Ask for Doug at extension 246. Try Checkered Flag Automotive Components (619-589-0321), for good prices, too.

You will notice that the hole in the headlight housing through which the wires pass is quite large. If left unsealed, it can allow water and/or dirt to get into the housing. Luckily, you can buy the Audi part to seal these holes. It is P/N 447 941 189 and costs about $3.23 (includes two rubber boots).

Aiming Euro Lights
(Sean Douglas)
There are two ways of aiming lights. One, professionals use specialized equipment like the expensive Hella European light aiming machine. These machines are few and far between, only a few dedicated European tuners have them on this side of the Atlantic. The operation is quite simple; the machine is placed in front of the car and is aligned with the center of the headlamp, then the machine is set for a declining gradient (1.2% for cars). The lights are turned on and adjusted until the beam image lines up with the alignment marks in the aiming machine. This is the best method for aiming headlamps, but since it is unlikely that one is available locally, the second option is to aim them yourself.

To aim your headlamps yourself, all that is required is a vertical wall and 25 feet of level ground in front. Park the car next to the wall and mark a line on the wall at the horizontal and vertical centers of the headlamps (black electricianís tape works well). This is the center-point. Next mark a horizontal line 3½ inches below the center mark. Back the car 25 feet straight back and turn on the low beams. Turn the left/right adjusting screw until the bright spot is inline with the vertical center mark. Then turn the up/down adjusting screw until the beam cut-off is inline with the lower horizontal line. Repeat for the other side. Its interesting to note that 3½ inches of vertical drop in 25 feet works out to a 1.2% gradient. If your headlamp unit has the low and high beams integrated, then you're finished. If your car has a separate high beam unit, then they should be aimed as well. Follow the same procedure, cover the low beams with a piece of cardboard (if both illuminate simultaneously), turn on the high beams and turn the adjusting screws until the brightest spot is inline with the center-point mark. Now you're done and you can enjoy your new lights!

(Jim Bush)
It is a good idea to upgrade the wiring when you upgrade to Euro lights. Click Here for the wiring diagram and parts list for a thrifty version. And click Here for a picture of it.
Quad-Round Conversion
Erebuni Corp. sells a conversion kit with 4 round headlights and replacement grille for about $350. It comes with wiring and does not require moving the turn sigs. 2Bennett also sells a quad-round kit (pictured at left) that is apparently better quality. I do not know what type of bulbs are used with these kits, but the quality of lighting is reportedly on par with the Euro lights. 

Auxiliary Lights and Bulb Upgrades
For those who don't want to spend the big bucks on Euro lights or quad-rounds, there are alternatives. You can just buy some high wattage "off-road" bulbs, but the stock wiring will likely melt, and more light just makes the problem worse because the fault is with the reflectors and lenses.  You cancorrect the wiring by following the procedure below, or Competition Ltd. (313-464-1458) sells a 9004 kit and Audi adapters for ~$80, which sounds like it takes care of the wiring problem. This will not only eliminate the risk of frying your light switch and wires, but gives more juice at the bulb for more output.

Hella and PIAA (800-525-7422), among others, make a wide variety of auxiliary driving lights. The big drawback with these is that you have to find someplace to mount the lights where they will be effective, steady, and not disrupt the airflow into the engine/radiator/etc, and you may not like the looks when you are done.

9004 to 9007 Bulb Conversion
(Brent Henry)
For a decent low-cost upgrade, you can convert your 9004 lights to use 9007 bulbs very easily. This will not make a dramatic difference, but most people say that it gives at least a little improvement.

  1. Remove the 9004 bulbs.
  2. Use a long, flat blade screwdriver and a mallet to snap off the two tabs in the bulb sockets located at about 5 o'clock and 8 o'clock. Leave the tab at 12 o'clock to orient the bulbs (same for both 9004 and 9007). This makes the socket compatible for both bulbs.
  3. Pull out the rubber moisture plug from the headlight connectors. Note the position of each colored wire. You will be swaping the positions of the brown and yellow leads. This is a difficult procedure that needs to be done in two steps: First you need to remove a piece (the top quarter) of the plastic casing of the connector itself, as it acts as a place-holder for the wires. Second, insert a very small jeweler's screwdriver into the open end of the connector (opposite from the end from the wires) on the top side (the side that you had to remove the plastic place-holder piece). The wires should pop out easily.
  4. Before you push the wires into their new positions, you should soak down the little rubber moisture plug with WD-40 and pull the 2 wires (and connectors) out through this plug and re-insert them into their new positions, then the plug will go back in nice and neat, otherwise with the wires crossed, it will not go back in very well.
  5. Insert the brown wire where the yellow one was originally, and vice-versa.
  6. Carefully push the moisture plug back in, angling the wires so that it all fits back together.
  7. Plug in the 9007s and go drive really fast at night.
(Bob Rossato)
Like all of the electrical wiring in Audis, the headlight wiring is a bit weak. Below are some instructions and tips for adding relays to power the bulbs directly from the battery or alternator, and just using the stock wires to trip the relays. This will give you more power at the bulbs and less strain on the original low gauge wires and headlight switch. Fooling the Autocheck System
(Igor Kessel)
Once you rewire your lights, the autocheck system will constantly complain about a burnt out bulb (as if you couldn't figure it out yourself!). Here is a procedure for permanently disabling (fooling, actually) the headlight circuit of the autocheck system. It's all done to one suspicious looking relay location.

The unit in question is located in the auxiliary relay panel, under the dash. Middle row, first on the right (position #6), looks like a standard Hella relay. It is not. It's is a logic controller, P/N 443 919 469B, built around a single chip (either a difference amplifier or a comparator, ULX245M a proprietary SOB). The chip listens to the current that flows through two very low reference resistors, comprised out of two 15mm wires no less than 1mm in dia, probably Ag (they are silver colour and have a very low resistance). The circuit listens to the impedances of the low beams filaments and throws a red flag (6v on terminal "K", goes to a thin grey wire, that is connected to the computer) if either of two conditions are met: 1. At least one filament is blown (R=infinity) or 2. R of one filament significantly differs from R of another one.

You want to shunt those calibrated reference wires. You need to connect 56bR to 56bR1 and connect 56bL to 56bL1. To do this without damaging the original controller, take an old (a burnt one is OK too) standard 4 or 5pin relay and gut it out. Then solder it's terminals in pairs so that when plugged in place of the OEM controller, the headlight circuits are complete, and the computer has no signal to cause it to cry. Or you can just pull the logic controller and make two short (3") jumper cables of 14-ga. wire, with a male spade bit (blue code) on each end. Then insert the spade bits into the relay connections to jumper both headlight circuits. Either way, the two smaller jacks in the controller socket, 31 and K, will be unused, so that the computer won't see a red flag on terminal K and be happy.

(I don't have a relay in front of me and don't want to mislead you. You figure it out, either 85+30 and 86+87 or 85+87 and 86+30. BE CAREFUL, try not to screw up here! Use a thick wire for soldering).

The diagram for the relay panel may mention that this relay position is also for oil pressure warning. That is true only for cars without the autocheck computer. If you do have the autocheck computer (and you do, otherwise you wouldn't be reading this section!), the oil pressure signals go straight into the autocheck unit in the instrument cluster, so this modification will not disable any autocheck functions other than the headlight warning.

The original DOT lenses are not replaceable, so if one gets shattered, you have to get a whole new headlight assembly. To keep this from happening, you have a couple of options:

Fog Lights
Stock P/N 895 941 699B & 700B
The stock fogs aren't too bad compared to the headlights. They're well integrated into the spoiler and they throw a decent amount of light through the projector lenses with a well defined upper cutoff. The pattern could be better, but their main disadvantage is price. The fogs on the Coupe Quattro are different from those on the 90 Quattro 20V. The Coupe fogs are similar to those used on the V6 model 90 sedans and the Cabriolet, and the 90Q20V fogs are the same as those used on all the earlier 80/90 cars. The lenses of the CQ fogs are not available separately, and the retail price is close to $200 each from the dealer for the whole fog light! The lenses on the 90Q20V fogs are replaceable (P/Ns 93 941 723B & 724B) but they're still about $100 each. For a better price, try calling Imported Car Parts of Poroco at (860) 693-0228. If you still have the OEM fogs, I highly recommend covering them with some StonGard (800-350-4897) or clear vinyl from Griot's Garage (800-345-5789).

Fog Lights On w/o Headlights
(Bob Nielsen, Hank Nisiewicz)
I've still got the stock fogs, and the biggest problem I had was that you could only turn them on when the headlights were on. The dispersion caused by the poor pattern of the headlights make the car almost undriveable in the thick stuff, with or without fog lights. To get around this all you have to do is remove the fog light relay under the hood  and replace it with a jumper wire.

  1. Remove negative lead from battery. If you have the stock stereo head unit, make sure you have the security code!
  2. The relay is in the main fuse/relay panel under the hood just below the bottom of the windshield on the driver's side. Open the fuse/relay panel cover, remove the first (horn) relay to the left. This allows easier access to the fog light relay directly behind it. Remove the fog light relay, too.
  3. Get a piece (about 1.5" long) of 16 AWG wire then crimp a spade lug on each end (you can find spade lugs that are about the same size as the relay contacts at any auto parts place). For ease of installation, the two spade lugs should be crimped oriented 90 degrees to each other.
  4. Plug the jumper into relay connector terminals #11 & #13 (where #30 and #87 on the relay would plug in), which are top and bottom and whose slots are oriented 90 degrees to each other.
  5. Reinstall the horn relay, reconnect the battery negative cable and test.
DISCLAIMER: Check your local laws. In some places it's illegal to run fogs w/o headlights, and doing so might cost you a steep fine. If you get caught, you didn't hear it from me.

Rear Fog On w/o Front Fogs
(Hank Nisiewicz)
If you use your rear fog light to discourage tailgaters, inform drivers of errant high beams, etc., you may have wished that the rear fog didn't activate the front fogs as well. Here are some instructions for disconnecting the front fogs from the rear fog switch:

  1. Remove negative lead from battery. If you have the stock stereo head unit, make sure you have the security code!
  2. Pry the rear fog switch out of the dash with a small, flat-blade screwdriver. It is usually easier if you remove the stereo head unit, then push the switch out from the back.
  3. You want to disconnect the White/Yellow wire that runs between terminal #4 of E18 (the rear fog light switch) and terminal #6 of E23 (the front fog light switch). You can just cut it, or try to pull it out of the connector, or remove the tab from the back of the switch, or you can open up the switch and disconnect it inside.
  4. Whatever you choose to do, make sure that both ends of that circuit are isolated (e.g., if you cut the wire, put electrical tape or wire nuts on both ends of the exposed wire). This is necessary because the switch side of the wire is live when the switch is on, but the other end of the wire is live when the FRONT fog switch is on.
  5. Reconnect the battery, test out both fog switches, then put it all back together.
Turn Signal Lenses
The standard orange turn signal lenses are about $45 and are shared with the other 80/90 series cars. However, you can get clear lenses that give the H4/H1 wrap-around look. I believe the Hella P/N is 2BA 005 296-801. (I don't know if that's the left or right.)

Christian Long has negotiated a great deal on these with the guy below. He has the InPro equivalents for about $85. Most places I've seen charge more than that much just for one! Just make sure you mention that you're part of the 20V list.

Ken Weidmann
Checkered Flag Automotive Components
(619) 589-0321
5330 Reservoir Dr.
San Diego, CA 92115

See also Door Locks, Body Seals, & Trim

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