Just look at the door jamb. The switch is a small black oval with a black plastic pin sticking out, held in by one screw. It is in the front of the door jamb, near the bottom.
Take the screw (Philips) out, fish out the switch, the wire unplugs. Clean up the metal base with some sandpaper, scotch-brite, small wire brush, or what ever. Clean the door jamb are under the switch, clean the screw. Put a little white grease (or corrosion preventitave of your choice) and reassemble in reverse order. Light will work right for at least 6 more months. then, just do it again
