What is the black reservoir mounted in left front wheel well on a 1998 cadillac?

The black reservoir mounted in the left front wheel well of a 1998 Cadillac is typically the windshield washer fluid reservoir. This component stores the fluid used to clean the windshield and is connected to the washer pump, which sprays the fluid onto the windshield when activated. Its location is designed for easy access for refilling and to keep it out of the engine bay, reducing the risk of heat exposure.