Power Mirror Position Sensors
WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2017 Honda Odyssey, 2016 Honda Odyssey, 2015 Honda Odyssey, 2014 Honda Odyssey, and 2013 Honda Odyssey. However, it is still accessible from the selected car via links, so may be relevant.
Using a tilt position sensor and a swing position sensor, the power mirror control circuit in the power mirror control unit detects the voltage changes created by the mirrors moving. These voltage changes are stored in memory, and the power mirror positions are memorized for each stored driving position.