1. Park your car in a safe location and turn off the engine.
2. Open the trunk of your car.
3. Locate the brake light assembly on the side of the trunk that contains the malfunctioning bulb.
4. Remove the trunk liner. Use the trunk pull handle and gently pull down to remove the liner.
5. Remove the two screws holding the brake light assembly in place.
6. Once the screws are removed, gently pry the brake light assembly out of its housing.
7. Remove the old brake light bulb by turning it counterclockwise.
8. Insert the new brake light bulb by turning it clockwise until it is secure.
9. Reinstall the brake light assembly by inserting it into its housing and replacing the two screws that you removed earlier.
10. Replace the trunk liner.
11. Close the trunk of your car.
12. Test the brake light to make sure it is working properly.
Here are some additional tips for replacing brake light bulbs on an Audi A4 2003:
* Use the correct type of brake light bulb for your car. The owner's manual for your vehicle will specify the correct type of bulb to use.
* Be careful not to drop the brake light bulb. If the bulb breaks, it can create sharp glass shards that can cause injury.
* If you are uncomfortable replacing the brake light bulb yourself, you can take your car to a mechanic to have the bulb replaced.
