This air door actuator directly replaces the original actuator on specific vehicle years, makes, models, configurations and positions to restore proper HVAC operation. Please note that many vehicles have several different air door actuators, which are designed for specific positions and functions in the vehicle. To ensure you have what you need, carefully review the application notes for this part to verify it matches the position and function of the actuator you need to replace. In some online ordering systems, you may need to enter your vehicle information first to see the application notes for your vehicle. If you don't know which actuator position you need to replace, consult a qualified service technician. This part is compatible with the following vehicles. Before purchasing, enter your vehicle trim in the garage tool to confirm fitment. [Cadillac STS: 2005, 2006, 2007, 2008, 2009, 2010, 2011]