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:
Tire Pressure Sensor Replacement (USA models)
Removal
notice
Each tire pressure sensor contains a lithium anode battery that is
not removable. The complete tire pressure sensor should be disposed of
according t ...
Valve Body and ATF Strainer Removal (A/T)
Remove the ATF feed pipe (A) from the regulator valve body (B).
Remove the ATF feed pipes (C) (D) from the servo body (E).
Remove the ATF strainer (F) (two bolts).
...