1999.5-2001 Audi A4 (B5) HID conversion installation instructions

1. Take the kit out of the box and lay everything out. You can install either the ballasts or bulbs first but typically it is easier to install the bulbs first.
2. There are 3 T27 torx screws holding the headlight on. The 2 on top are visible in this picture.
3. with the 2 screws removed.
4. The third screw is shown here. A long extension is needed to get to it and an extendable magnet is helpful to retrieve the screw (or bit if it falls).
5. Disconnect the headlight and turn signal connectors and remove the headlight by pulling it toward the outside of the car and toward you.
6. Drill a 1” hole in the center of the cap as shown. If you use a hole saw that will be all you need. If you use the small drill bit you will need to use your dremel to cut a 1" hole. You may want to use some sand paper just to smooth the edges you have cut.
7. Some of the bulbs come with adaptors that some other cars require. The Audi installation does not require them. Take your pliers and cut them off. This will allow you to remove the base of the bulb case later on.
8. Feed the AMP connector ends of the bulbs through the hole from the inside out and seat as shown. Seal the provided 1" gasket in the hole you have made. You should have two connectors coming out of the same side as the bulb that will eventually connect to the OEM harness - these will be connected later. Leave the bulb in the case for now.
9. Now mount the ballast to the underside of the headlight housing with the double-sided tape provided. The square opening is perfect to mount the ballast to but other locations are possible also. There will be extra wiring so try to tie it up out of the way.
10. Take the headlight over to your car so you can reconnect the wiring. Plug the connector coming out of the outside of the cap to the ballast connectors. Plug in the black and red wires coming out of the inside of the cap to the OEM bulb harness. It should not matter which wire connects to which in the case of the H7 connectors, but I connected the red wire to the purple wire side and the black to the brown wire side of the OEM harness. See below for troubleshooting if one or both do not light up.
11. Now reinstall the headlight in the reverse order you uninstalled it and turn them on to make sure they light up properly.

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