FORD 2011 Focus v.2 - Manual (Page 268)

• Mobile communications systems may harm the operation of your
vehicle, particularly if they are not properly designed for automotive
use.
• To avoid interference with other vehicle functions, such as anti-lock
braking systems, amateur radio users who install radios and antennas
onto their vehicle should not locate the Amateur Radio Antennas in
the area of the driver’s side hood.
• Electrical or electronic accessories or components that are added to
the vehicle by the authorized dealer or the owner may adversely affect
battery performance and durability.
Accessories
268
2011 Focus (foc)
Owners Guide, 2nd Printing
USA (fus)