To be sure, you'll likely need to:
* Consult your owner's manual: This is the best source for the precise location in your specific vehicle.
* Check online forums: Search for "1991 Buick Park Avenue inertia switch location" on forums dedicated to Buick or classic car repair. Owners often post pictures and detailed instructions.
* Look carefully under the passenger-side dash: Feel around for a small, usually square, box-like component. It might be attached to the underside of the dash or in a nearby area. You may need a flashlight.
Remember to be cautious when looking under the dashboard; avoid disconnecting anything unnecessarily.