The power steering pump produces high pressure, by compressing the power steering fluid, in order to reduce the effort required to steer a vehicle. A power steering pump replacement is needed when the power steering pump no longer produces pressure and steering becomes more difficult.
To perform a power steering pump replacement the fan belt is removed along with the hardware securing the power steering pump to the engine. The power steering fluid is removed form the reservoir and the fluid lines are removed from the pump. The old power steering pump is replaced with a new one and the system refilled with fresh fluid. Then the vehicle is driven and the system is checked for leaks.
Most manufacturer factory warranties cover the cost of a power steering pump replacement as long as the failure is due to a manufacturer defect or workmanship. There are some extended auto warranties that will cover the cost of a power steering pump replacement as well.