I have been waiting a long time for someone to release a navigation unit that is affordable and integrates well in our cars. The Pioneer AVIC-D3 fits the bill. This double DIN unit is feature rich, having almost everything that you would want including optional full Ipod control, traffic, optional digital radio, Bluetooth, DVD player, etc... (see Pioneer site for full detail). What did it for me was the user selectable button illumination color. The end result is shown in the following pictures.

As you can see the red buttons matches our interior lighting very well.

Now for the actual installation.
Adaptors/connectors needed:

Description: Volkswagen 1980-2005 Wire Harness
Cat #: 70-1784
Note: Use this if you are going to use the AVIC to lay you own wire to the back speakers. Does not include the 20-pin connector

Description: VW AUDI amplified Wire Harness
Cat #: 70-1787
Note:Use this if you want to use the built in rear speaker amplifier with stock wiring, or if you have the Bose unit. This has both the dual 8-pin as well as the 20-pin connectors

Description: VW/AUDI/European vehicle antenna adapter cable
Cat #: 40-VW54
Note: The stock Symphony unit antenna connector feed power to the antenna amplifier but the Pioneer does not so we need this adapter

Description: AUDI A4 2000-01 dash kit
Cat #: 99-9105
Note: Dash trim kit for the 2000-2001 A4, includes dash plate and mounting brackets, I ended not using the dash plate

Block III, Metra dual 8-pin Speed sensor, use spare wire from harness
Symphony Pin # 1, GA
Metra harness black/white (I inserted)
AVIC power harness pink

Block III, Metra dual 8-pin Switched + 12 V
Symphony Pin # 4, S
Metra harness red
AVIC power harness red

Block III, Metra dual 8-pin Illumination
Symphony Pin # 6, I
Metra harness orange/white
AVIC power harness orange/white

Block III, Metra dual 8-pin Battery , always powered +12 V
Symphony Pin # 7, +
Metra harness yellow
AVIC power harness yellow

Block III, Metra dual 8-pin Ground
Symphony Pin # 8, -
Metra harness black
AVIC power harness black

Block II, Metra dual 8-pin Right front speaker +
Symphony Pin # 3, RF +
Metra harness gray
AVIC power harness gray

Block II, Metra dual 8-pin Right front speaker -
Symphony Pin # 4, RF -
Metra harness gray/blue
AVIC power harness gray/blue

Block II, Metra dual 8-pin Left front speaker +
Symphony Pin # 5, LF +
Metra harness white
AVIC power harness white

Block II, Metra dual 8-pin Left front speaker -
Symphony Pin # 6, LF -
Metra harness white/blue
AVIC power harness white/blue

Here we use the AVIC line output to feed to the rear powered speakers

Block I, Metra 20-pin Left rear +
Symphony Pin # 1, LR
Metra harness LR white RCA
AIC audio harness white RCA connector

Block I, Metra 20-pin Right rear
Symphony Pin # 2, RR
Metra harness RR red RCA
AIC audio harness red RCA connector

Block I, Metra 20-pin Common
Symphony Pin # 3, COM
Metra harness already in RCA
AIC audio harness already in RCA

Block I, Metra 20-pin Amp. control signal
Symphony Pin # 6,
Metra harness pos 6 wire
AIC audio harness blue/white

The reserve signal must be connected so that he AVIC knows when the vehicle is moving in reverse. The violet/white wire on the AVIC power harness must be connected to the blue/white wire on the brown connector using the provided crimp connector as shown on the following picture. This can be found behind the kick panel which is located on the driver side, left to the clutch pedal area. The panel is retained by two screws. The picture does not show the white strip on the blue wire, but it's there. If you are unsure use a voltmeter to find the wire that register +12V when the car is put into reverse (you can switch the key to on but not start the engine to test).

Since I didn't feel like hunting the parking brake wire down, I decided to implement the AVIC-D3 hack which permits all functions to be accessible even when the vehicle is moving. Obviously, use you own judgment when driving, keep your attention on the road.

Basically you will need to move the yellow/black (mute function) wire on the AVIC audio harness from the original location to an adjacent position as shown in the avic411 forum. Then ground this and the parking brake wire (light green wire on the AVIC power harness).

The antenna amplifier is powered through the Metra antenna adaptor by connecting it to the blue wire on the AVIC power harness.

The GPS antenna can be placed at various locations. I understand that GPS equipped Audis used to have the antenna on the rear deck nearby the right speaker. You can route it there if you want but for convenience, I opted to put the AVIC GPS antenna on the front dash as shown in this picture. The reception from the GPS satellites seems to be more than adequate. The antenna has a magnetic base and has to be placed atop a square metallic plate that is supplied by Pioneer. The antenna wire can be tucked between the dash and the bottom of the windshield.

I fed the antenna wire through the base of the passenger A pillar and ran it above the glove box to the center consol. I used some the supplied adhesive wire holder to keep it in place and tied the extra length to the right of the glove box as shown below.

In the end you end up with a lot of wire that must be stuffed behind the Pioneer unit. Fortunately, there is sufficient room.

The most difficult part for me was to mount the Pioneer unit in the spot where the Symphony radio occupied. You can use the Metra dash kit for this but I found that while the front plate does fit our car well, it does not fit the AVIC-D3 at all. There is an unacceptably large gap between the plastic trim piece and the screen. However, I did use the Metra mounting brackets that screw onto the side of the AVIC in order to provide support for the back of the unit. I shimmed the AVIC vertically by using some plastic pieces secured by double sided tape at the bottom as seen in this picture. The unit was then secured using custom L-brackets made from metal strips. I also used plastic pieces as spacer as seen in the following picture. There are some extra mounting holes on to the side of the AVIC for screwing the brackets. I took advantage of the two hex head screws that were nearby to secure the brackets to the center console. Adjusting the length of the L-brackets was by trial and error and took the most time.

Once the unit is secured, I took some measurements and fabricated a trim piece from 1/8” polycarbonate plastic I had. The main rough cuts were made using a hack saw, metal cutting blade work well. I recommend cutting the external sides first then cut the internal rectangular hole. I finished the edges using a file.

Painting was a pain for me. I had to redo the paint job several times. Finally after the third attempt, I obtained the result I wanted. The steps are:

1) sand surface, very fine, wash & dry
2) thin primer coat
3) sand, very fine, extra fine, super fine to get good smooth surface, clean and dry
4) first coats of semi gloss black, very light layer, dry
5) light sanding, super fine, wash & dry
6) repeat steps 3-4 twice more, obviously don't sand after the final coat

Letting dry for one day between each operation is critical to get a good finish. I also found that warming the spray can in some hot water helped provide a more uniform layer.

The trim piece was attached to the center console by using some strong little rare earth magnets. The top magnet was secured by double sided tape, the bottom smaller ones simply stuck on the screw already present. On the trim piece I attached small blocks of ½” thick plastic onto which I taped holes which were later populated by #4-40 flat head steel screws. This allowed me to adjust the position of the trim plate to be flushed with the rest of the center console.

In the end, I am pleased with the unit. The navigation is very accurate and the sound from this system is significantly better than the stock radio. In addition, as you can see from above, custom background pictures can be uploaded to the unit from a CD-R.