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:
iPod®
...
Changing the Engine Oil and Filter
Always change the oil and filter according to the maintenance messages shown
on the information display. The oil and filter collect contaminants that can damage
your engine if they are not removed ...
Warm Up TWC Removal/Installation
NOTE: If the warm up TWC is damaged internally, inspect the under-floor TWC
for debris.
Raise the vehicle on a lift.
Remove the bolts (A).
Lower the vehicle.
...