Hi Keith, I'm glad to assist you. The cooling fan module plays a crucial role in the vehicle's cooling system by controlling the operation of the cooling fans based on the engine's temperature and other inputs. It helps maintain the optimal engine temperature, prevent overheating, and ensure efficient engine performance. The part that controls the blower motor fan speed is the blower motor resistor. For us to check carefully and be accurate on the part you need, please provide the complete details of your vehicle (year, make, model, submodel, 2WD/4WD, and engine size). The VIN would be helpful. You can also call our parts specialist (for real-time live & immediate assistance) on our toll-free number, 1-866-529-0412 (Mon to Sun).