I only have the P3200BT and have not installed the Navi on it. Don't know if it'll work for the Navi as well. From wut I've researched, there's an accelerometer in the GPS which knows when the vehicle will go above 10mph, and deactivates certain functions for safety purposes. The accelerometer cannot be turned off via electronic signals. Im not sure how to solve this yet, and i've emailed the avhbypass.com people for help. hopefully they come back w/ an answer soon.