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:
Precautions for Opening/Closing the Tailgate
Always make sure individuals and objects are clear of the tailgate before
opening or
closing it.
■ Opening the tailgate
• Open the tailgate all the way.
►If it is not fully opened, ...
System Initialization
The navigation system must be initialized if
power to the navigation system is
interrupted for any reason (e.g., the
battery was disconnected). ...
Rocker Arm Assembly Installation
If the rocker arm assembly is disassembled, reassemble the rocker arm
assembly.
Apply engine oil to the end of the valve stem.
Install the rocker arm assembly.
...