1. Safety First:
* Park on a level surface and engage the parking brake.
* Turn off the ignition and let the car cool down. Working on a hot bulb can cause burns.
* Wear safety glasses. Broken glass can be a hazard.
2. Accessing the Brake Light:
* Open the tailgate/rear hatch.
* Locate the brake light assembly. It's usually a unit containing both the brake light and the turn signal. You may need to remove the interior trim panel (covering the light) to access the bulbs. This usually involves unsnapping or removing clips. Consult your owner's manual or an online repair guide specific to your Audi A4 Avant's year for detailed instructions on removing the trim panel. Some models might require removing the entire taillight assembly.
3. Removing the Old Bulb:
* Once you've accessed the bulb holder, carefully remove it. This usually involves a quarter-turn or pulling it straight out. Be gentle; the bulb socket is often fragile.
* Carefully remove the old brake light bulb. Avoid touching the glass part of the bulb with your fingers – use a clean cloth or paper towel.
4. Installing the New Bulb:
* Check the bulb type. Your owner's manual or a parts store should specify the correct bulb type. Common types include 1156, 1157, or 3157.
* Insert the new bulb into the socket, ensuring it's properly seated.
* Push the bulb holder back into place and secure it.
5. Testing and Reassembly:
* Close the tailgate and test the brake light. Turn on the brake lights and check if the new bulb is working.
* Reassemble the interior trim panel if necessary.
Important Considerations:
* Owner's Manual: Your owner's manual is your best resource. It will have diagrams and specific instructions for your model year.
* Online Repair Guides: Websites like YouTube and repair manuals (e.g., Haynes, Chilton) often have videos and detailed guides specific to Audi A4 Avants. Search for your year and model.
* Bulb Type: Get the correct bulb type. Using an incorrect bulb can cause issues with fit, brightness, and even damage to the electrical system.
* If the brake light still doesn't work: Check the fuse, the wiring, or potentially consult a professional mechanic if you're not comfortable troubleshooting further.
Disclaimer: This is general guidance. Procedures can vary depending on the model year and specific trim level of your Audi A4 Avant. Always refer to your owner's manual or a reliable repair guide for detailed, year-specific instructions before attempting any repairs. Improperly replacing the bulb could damage your vehicle's electrical system.
