2009 Audi S4 Radiator Fan Motor Replacement Cost

The engine in a vehicle gets hot when it is running because of friction caused by its internal moving parts. While the engine oil helps to reduce the friction, the cooling system circulates coolant (also known as antifreeze) through the engine to manage the temperature. Once the coolant leaves the engine, it cycles through the radiator, where wafer-like ribbons, or “fins,” of aluminum absorb the heat and allow it to dissipate in the air that passes through the radiator. The engine’s cooling fan helps to draw a higher volume of air through the radiator, especially when the car is at a standstill, so that the coolant temperature decreases. For the most part, electric cooling fans are controlled by the same computer that controls the engine. However, in some engines, the fans are turned on and off by a temperature-sensitive switch mounted in either the radiator or elsewhere in the cooling system.

If the fan motor does not work, there will not be enough air movement through the radiator to dissipate the heat in the coolant. The symptom usually associated with a faulty fan motor is an overheated engine. Signs include a temperature warning gauge on the dashboard, steam coming from the engine compartment or from under the front of the car, or sluggish engine performance. A check engine light might come on if a cooling fan motor is inoperative. A blown fuse on the fan circuit could indicate a problem with the fan motor as well.