Where might a cabin air filter be located aside from under the dashboard?

A cabin air filter is designed to clean the air that enters the vehicle's interior through the heating, ventilation, and air conditioning (HVAC) system. In addition to being located under the dashboard, it can often be found inside the engine compartment. This location allows it to filter air before it enters the passenger area, effectively trapping dust, pollen, and other airborne particles, thus enhancing the air quality within the vehicle.

While the other locations mentioned—such as the headliner above the passenger's seat, under the rear seat, or under the vehicle—are not typical for the placement of cabin air filters. The headliner does not facilitate airflow from the outside; under the rear seat and under the vehicle do not connect to the HVAC system, making them unsuitable locations for a filter intended to purify the air entering the cabin.