Operating Check
WARNING: This page is about a different car, the 2004 Infiniti M45 and 2003 Infiniti M45. However, it is still accessible from the selected car via links, so may be relevant.
Depress brake pedal several times with engine off, ensuring pedal stroke does not change. Depress brake pedal, and then start engine. If pedal goes down slightly, operation is normal. If pedal does not go down slightly, check for vacuum leak between vacuum source and booster.