The headlamp switch is located in the instrument panel, outboard of the steering column. It closes a path to ground for the instrument cluster chime warning circuitry when the park or head lamps are on and the driver door jamb switch is closed (driver door is open). The headlamp switch opens the ground path when the headlamp switch is turned off.
The headlamp switch cannot be repaired and, if faulty or damaged, it must be replaced. Refer to Group 8E - Instrument Panel Systems for the service procedures.