IPDM E/R
WARNING: This page is about a different car, the 2012 Infiniti QX56. However, it is still accessible from the selected car via links, so may be relevant.
IPDM E/R has steering lock relay, starter relay and starter control relay inside. Steering lock relay is used for the steering lock/unlock function. Starter relay and starter control relay are used for the engine starting function. IPDM E/R controls these relays while communicating with BCM.