1. Open the trunk by pressing the button in the driver's door.
2. Look for the tail light bulb housings on the inside rear quarters.
3. Grasp the black plastic retainer ring and turn counterclockwise to release it.
4. Pull back on the retainer ring and remove the bulb from the housing.
5. Check the metal contacts in the bulb housing and gently wipe them with a cloth or cotton swab to remove any debris or corrosion.
6. Insert the new bulb into the housing and turn it gently until it locks in place.
7. Replace the bulb housing retainer ring by turning it clockwise until it clicks into place.
8. Repeat steps 3-7 to replace the tail light bulb on the opposite side of the vehicle.
9. Close the trunk.
That's it! The new tail light bulbs should now be functional in your VW Passat. Please note that it's important to use the correct bulb type specified for your vehicle to avoid any fitment or performance issues. If you have any difficulty or are not confident in performing the task, consult with a qualified mechanic.