WARNING: This page is about a different car, the 2003 Infiniti I35. However, it is still accessible from the selected car via links, so may be relevant.
Check resistance between terminals 1 (R/Y), 2 (PU) and 3 (B).
Fig 1: Checking Resistance Between Terminals 1 (R/Y), 2 (Pu) And 3 (B)