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:
Emissions Controls
The burning of gasoline in your vehicle’s engine produces several byproducts.
Some of these are carbon monoxide (CO), oxides of nitrogen (NOx), and hydrocarbons
(HC).
Gasoline evaporating from t ...
Command Input
If the system does not understand a command or you wait too long to give a
command, it responds with “Pardon? No command was heard. Please press the talk
button and say a command.”
When you giv ...
Rear Brake Shoe Replacement
caution
Frequent inhalation of brake pad dust, regardless of material composition,
could be hazardous to your health.
Avoid breathing dust particles.
...