Operating Check
WARNING: This page is about a different car, the 2007 Nissan Sentra. However, it is still accessible from the selected car via links, so may be relevant.
With the engine stopped, change the vacuum to the atmospheric pressure by depressing brake pedal several times at intervals of 5 seconds.
Then with brake pedal fully depressed, start engine and when the vacuum pressure reaches the standard, make sure that the clearance between brake pedal and floor panel decreases.