I don't think it had to do with the tires the power steering pump is electric so it hums when you turn the wheel. While the car is just sitting still you should see some fluid movement when you look at the pump.
There is a few wires that are attached to the pump bracket the bracket has a edge on it and might of cut one of the wires this was a known issue. Take a look at all the wires that go,to the pump for chaffing
There is a few wires that are attached to the pump bracket the bracket has a edge on it and might of cut one of the wires this was a known issue. Take a look at all the wires that go,to the pump for chaffing