You need to disconnect the cable from the battery's negative terminal. To remove the battery, if you're working on a Pathfinder with a 3.5L V6, it will be easier to get to the pump. In case you're dealing with a Pathfinder with a 3.3L V6 engine, raise the front of the vehicle and secure it firmly on jack stands. Take off the under-vehicle splash shield. On a Frontier or Xterra having four-cylinder engine, remove air filter housing and air intake duct above radiator. Remove the drive belt. You should detach the pressure line and return hose from pump. Get rid of sealing washers from either side of pressure line banjo fitting; new ones must be used during installation afterward. Block hoses in order to keep out contaminants. Unscrew mounting fasteners and take pump out of vehicle without spilling any fluid onto painted surfaces around it carefully. NB: On models which have holes in pulley, access for front mounting bolts is through pulley holes. Position pump in mounting bracket and fit mounting fasteners into place. Tighten fasteners until torque is achieved. Attach pressure line and return hose to pump as well as ensure that new sealing washers are used on pressure line fitting then tighten banjo bolt onto it up to torque specifications given by manufacturers of this vehicle component alone. Put back drivebelt and adjust its tension accordingly. The rest of the installation is just like dismounting but backwards process instead.Fill power-steering reservoir with prescribed fluid and purge system per next down mentioned steps.