Lincoln 2011 MKZ Hybrid - Manual (Page 241)

The CTA system detects vehicles approaching up to 45 feet (14 meters)
away (approximately the width of five parking spaces). Coverage
decreases when vehicles and objects in close proximity block the CTA
sensors (refer to figure for approximate zone coverage areas [sensor
obstructed to vehicle on left]). Backing slowly from the parking spot
in these situations helps to increase the sensor coverage and
effectiveness.
CTA coverage also decreases when parking at shallow angles (refer to
figure for approximate zone coverage areas [sensor obstructed to
vehicle on left]).
Driving
241
2011 MKZ Hybrid (hkz)
Owners Guide, 1st Printing
USA (fus)