Once all the contacts are clean, apply a light film of silicone electrical grease (NOT dielectric, thermal, or chassis; or battery snot, or anti-seize, or conductive grease), then carefully reassemble the switch. It may be necessary to use a piece of paper to ramp the headlight contacts into their slot. Install a screw near the hazard switch first. '92-97 F-series/Broncos use
Motorcraft SW5591.
Upper Connector
Motorcraft WPT-611Lower Connector
Motorcraft WPT-179Electrical Grease (F8AZ-19G208-AA)