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:
Map Update
INFO button
►Map Update
Update the map database.
When you order a map update, it is mailed to
you on a USB flash drive. ...
Auxiliary Input Jack
U.S. Sport and all Canadian models
The auxiliary input jack is underneath the accessory power socket in the center
pocket. The system will accept auxiliary input from standard audio accessories.
...
Inspection
Install the flange nut on the damper shaft end, and set the socket wrench
and T-handle on the nut.
Compress the damper assembly by hand, and check for smooth operation
through ...