DTC B210A: Steering Lock Condition Switch: Description
WARNING: This page is about a different car, the 2008 Infiniti EX35. However, it is still accessible from the selected car via links, so may be relevant.
There are 2 switches in the steering unit. IPDM E/R compares those 2 switches conditions to judge the present steering status and transmit the result to BCM via CAN communication.