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:
Engine Block Drain Bolt/Sealing Bolt Installation
NOTE:
When installing the drain bolt (A), always use a new washer.
When installing the sealing bolt(s) (B), always use a new bolt(s) and
washer(s) (C).
...
Changing a Flat Tire
If you have a flat tire while driving, stop in a safe place to change it.
Drive slowly along the shoulder until you get to an exit or an area to stop that
is far away from the traffic lanes.
The ...
DOT Tire Quality Grading (U.S. Vehicles)
The tires on your vehicle meet all U.S. Federal Safety Requirements. All
tires are
also graded for treadwear, traction, and temperature performance according
to Department of Transportation (DOT) ...