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:
Disassembly
Compress the damper spring, then remove the nut (A) while holding the
damper shaft with a hex wrench (B). Do not compress the damper spring more
than necessary to remove the nut.
...
Transmission End Cover Transmission Fluid Pressure Switch Replacement (A/T)
Remove the transmission fluid pressure switch A (2nd clutch) (A).
Make sure there is no water, oil, dust, or foreign particles inside the
connector.
Install the new tr ...
Accessory Power Socket Test/Replacement
NOTE: If the accessory power socket does not work, check the No. 13 (20 A) fuse
in the under-dash fuse/relay box and ground (G502) first.
Remove the dashboard center lower trim.
...