On a 2001 Toyota Avalon How can you stop a squeaking noise while turning steering wheel?

The most common cause for a squeaking noise when turning the steering wheel on any vehicle, including a 2001 Toyota Avalon, is the belt that runs the Power Steering pump. If the belt is fairly new, a small drop of any dish soap on the belt while the car is running will clear up the noise. If the belt is worn, it needs to be replaced.