Your Honda Civic tail lights may burn out over time, and this is normal. However, sometimes there are other issues with the tail lights that are not related to the bulbs. Before replacing any components, you should thoroughly troubleshoot the tail lights. Fortunately, there are only a few components that can go wrong on your Civic's brake light system.
Open the fuse panel under the steering wheel and check the fuse for the tail lights. Pull the fuse using the fuse pullers in the fuse panel. Check the metal strip inside the fuse to make sure that it is not burnt out or broken. If it is, then you must replace it with a fuse of the same amperage.
Check the brake light switch. Press down on the brake pedal. Listen for a "click" as you press down on the brake pedal. If you do not hear this single "click," then your brake light relay switch is broken and needs to be replaced.
Press on the brake lights and have an assistant check the lights. If they do not light up, you need to replace the bulbs in the tail light housing.
For specific information about your model year Honda Civic tail lights, consult the particular vehicle's manual. (See Resources)