Which component is responsible for circulating air through the cabin?

• A. Indicator Lights
• B. Blower Motor Operation
• C. Windshield Wipers
• D. Cab Lubrication Points

Answer: (B)

Circulating air through the cabin is driven by the blower motor, the fan in the vehicle’s HVAC system. When it operates, it pushes air through the heater core or evaporator and out through the dash, floor, or defrost vents, moving it into and around the cabin. The speed control adjusts how much air is moved. The other items listed don’t move air: indicator lights show system status, windshield wipers sweep the windshield, and lubrication points relate to maintaining moving parts. So the blower motor operation is what actually circulates air inside the cabin.