Ford Fiesta Owner's Manual page 205

WARNING: Keep batteries out of reach of children. Batteries
contain sulfuric acid. Avoid contact with skin, eyes or clothing.
Shield your eyes when working near the battery to protect against
possible splashing of acid solution. In case of acid contact with skin or
eyes, flush immediately with water for a minimum of 15 minutes and
get prompt medical attention. If acid is swallowed, call a physician
immediately.
WARNING: Battery posts, terminals and related accessories
contain lead and lead compounds. Wash hands after handling.
Your vehicle is equipped with a Motorcraft maintenance-free battery
which normally does not require additional water during its life of
service.
Note: If your battery has a cover/shield, make sure it is reinstalled after
the battery has been cleaned or replaced.
For longer, trouble-free operation, keep the top of the battery clean and
dry. Also, make certain the battery cables are always tightly fastened to
the battery terminals.
If you see any corrosion on the battery or terminals, remove the cables
from the terminals and clean with a wire brush. You can neutralize the
acid with a solution of baking soda and water.
It is recommended that the negative battery cable terminal be
disconnected from the battery if you plan to store your vehicle for an
extended period of time.
Battery relearn
Because your vehicle's engine is electronically controlled by a computer,
some control conditions are maintained by power from the battery. When
the battery is disconnected or a new battery is installed, the engine must
relearn its idle and fuel trim strategy for optimum driveability and
performance. To begin this process:
1. With the vehicle at a complete stop, set the parking brake.
2. Put the gearshift in P (Park) (automatic transmission) or the neutral
position (manual transmission), turn off all accessories and start the
engine.
2013 Fiesta (fie)
Owners Guide gf, 1st Printing
USA (fus)
Maintenance 205