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■ Objects which the system may not properly detect 
The shape of the object may prevent the sensor from detecting it. Pay partic- 
ular attention to the following objects: 
● Wires, fences, ropes, etc. 
● Cotton, snow and other materials that absorb sound waves 
● Sharply-angled objects 
● Low objects 
● Tall objects with upper sections projecting outwards in the direction of your 
vehicle 
■ Situations in which the system may not operate properly 
Certain vehicle conditions and the surrounding environment may affect the 
ability of a sensor to correctly detect objects. Particular instances where this 
may occur are listed below. 
● There is dirt, snow, water drops or ice on a sensor. (Cleaning the sensors 
will resolve this problem.) 
● A sensor is frozen. (Thawing the area will resolve this problem.) In espe- 
cially cold weather, if a sensor is frozen the sensor display may be displayed
abnormally, or objects, such as a wall, may not be detected. 
● On an extremely bumpy road, on an incline, on gravel, or on grass. 
● When vehicle horns, vehicle detectors, motorcycle engines, air brakes of 
large vehicles, the clearance sonar of ot her vehicles or other devices which 
produce ultrasonic waves are near the vehicle 
● A sensor is coated with a sheet of spray or heavy rain. 
● If objects draw too close to the sensor. 
● When a pedestrian is wearing clothing that does not reflect ultrasonic waves 
(ex. skirts with gathers or frills). 
● When objects that are not perpendicular to the ground, not perpendicular to 
the vehicle traveling direction, uneven, or waving are in the detection range. 
● Strong wind is blowing 
● When driving in inclement weather such as fog, snow or a sandstorm 
● When an object that cannot be detected is between the vehicle and a 
detected object 
● If an object such as a vehicle, motorcycle, bicycle or pedestrian cuts in front 
of the vehicle or runs out from the side of the vehicle 
● When a sensor or the area around a 
sensor is extremely hot or cold. 
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● When vehicle horns, vehicle detectors, motorcycle engines, air brakes of 
large vehicles, the clearance sonar of ot her vehicles or other devices which 
produce ultrasonic waves are near the vehicle 
● If the front of the vehicle is raised or lowered due to the carried load 
● If the orientation of a sensor has been changed due to a collision or other 
impact 
● Driving close to columns (H-shaped steel beams, etc.) in multi-story parking 
garages, construction sites, etc. 
● If the vehicle cannot be driven in a stable manner, such as when the vehicle 
has been in an accident or is malfunctioning 
● When tire chains, a compact spare tire or an emergency tire puncture repair 
kit are used. 
● On an extremely bumpy road, on an 
incline, on gravel, or on grass