To find it:
1. Locate the underhood fuse box: It's usually a black plastic box near the battery.
2. Open the fuse box: There should be a cover with a diagram showing the fuse layout and what each fuse controls.
3. Consult the diagram: Carefully examine the diagram to identify the fuse related to interior lamps or courtesy lamps. The amperage rating might be printed on the fuse itself, and on the diagram.
4. Check the fuse: Visually inspect the fuse for a blown filament (a broken wire inside).
If you can't find it easily using the diagram, you might need to refer to your owner's manual for a more detailed fuse box diagram. It's also possible that a relay or a switch could be the problem, if the fuse itself isn't blown.