Graco has been a leader in baby products ever since the company was founded in the early 1950s. It produces everything from monitors to car seats, with portable Pack 'n Plays (also called play yards or portable bassinets) being some of the most popular items. The problem with these Pack 'n' Plays is that some of them rely on batteries in order to operate vibrate and mobile features. These need to be changed, but the basic assembly manuals released by Graco don't really show how to do this.
Make sure that the mobile or vibration feature is turned off on the pack 'n play.
Locate the screws that are holding the battery compartment lid in place. Usually there are just one or two of these depending on the model.
Unscrew the screws and lift off the battery compartment lid.
Pull out the dead battery or batteries used by your specific model and replace them with the new ones.
Position the battery compartment lid back in place over the new batteries. Fasten the screws and make sure the lid is secure.