1. Park your Audi TT on a level surface and turn off the engine.
2. Open the hood.
3. Locate the sidelight bulb housing. It is located on the side of the headlight housing, near the front of the car.
4. Turn the sidelight bulb housing counterclockwise to remove it.
5. Remove the old sidelight bulb from the housing.
6. Insert the new sidelight bulb into the housing.
7. Turn the sidelight bulb housing clockwise to secure it in place.
8. Close the hood.
9. Turn on the sidelights to test the new bulb.
