Key Switch And Ignition Knob Switch
WARNING: This page is about a different car, the 2008 Infiniti FX45 and 2008 Infiniti FX35. However, it is still accessible from the selected car via links, so may be relevant.
Check continuity between terminals 3 and 4.
3 - 4
When key is inserted to ignition key cylinder : Continuity should exist.
When key is removed from ignition key cylinder : Continuity should not exist.