Depending on the length of time the power was interrupted, your system may require GPS initialization.

If initialization is not necessary, the system proceeds directly to the Startup Confirmation screen.
If the system fails to locate a sufficient number of satellites to locate your position within 10 minutes, the following screen is displayed.

If you are experiencing GPS reception problems:
During Route Guidance
During route guidance, route information is displayed on the map/guidance
screen.
Press the MAP/GUIDE button to display the guidance screen. ...
Accessories and Modifications
WARNING
Improper accessories or modifications can
affect your vehicle’s handling, stability, and
performance, and cause a crash in which
you can be seriously hurt or killed.
Follow all instru ...
Adjusting the Mirrors
Keep the inside and outside mirrors clean and
adjusted for best visibility.
Adjust the mirrors before you start driving. ...