Output Speed Sensor (Secondary Speed Sensor)
WARNING: This page is about a different car, the 2007 Nissan Sentra. However, it is still accessible from the selected car via links, so may be relevant.
The shift pattern is changed in accordance with throttle position when an unexpected signal is sent from the output speed sensor (secondary speed sensor) to the TCM. The overdrive-off mode is inhibited, and the transaxle is put in "D".