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:
Driving
Manual Transmission
Automatic Transmission
● Shift to P and depress the brake pedal when starting the engine.
Shifting
Park
Turn off or start the engine.
Transmission is locked.
R ...
Reporting Safety Defects
In the U.S.
If you believe that your vehicle has a defect which could cause a crash or
could cause injury or death, you
should immediately inform the National Highway Traffic Safety Administration ...
Drive Belt Auto-Tensioner Pulley Replacement
Remove the auto-tensioner.
Remove the tensioner pulley.
Install the tensioner pulley in the reverse order of removal.
Install the auto-tensioner.
...