1. Gather your tools and materials. You will need a Philips head screwdriver, a flat-head screwdriver, and a replacement interior light bulb.
2. Turn off the power. Before you begin working on the interior lights, turn off the power to the car by turning the ignition switch to the "Off" position.
3. Locate the interior light fixture. The interior light fixtures in a 1999 Toyota Corolla are located in the center of the ceiling, above the rearview mirror.
4. Remove the old light bulb. Use the flat-head screwdriver to pry open the lens cover of the light fixture. Once the lens cover is open, you will see the old light bulb. Use the Phillips head screwdriver to loosen the bulb and remove it from the socket.
5. Install the new light bulb. Take the new light bulb and insert it into the socket. Hand-tighten the bulb until it is secure.
6. Replace the lens cover. Replace the lens cover of the light fixture and press it firmly until it snaps into place.
7. Test the light. Turn on the power to the car and turn on the interior lights to make sure that the new bulb is working properly.
That's it! You have now successfully replaced the interior lights in your 1999 Toyota Corolla.
