Toyota Corolla Instruction Manual page 253

 Sensor detection information
 Certain vehicle conditions and the surrounding environment may affect the
ability of the sensor to correctly detect obstacles. Particular instances where
this may occur are listed below.
• There is dirt, snow or ice on the sensor.
• A sensor is frozen.
• A sensor is covered in any way.
• The vehicle is leaning considerably to one side.
• On an extremely bumpy road, on an incline, on gravel, or on grass.
• The vicinity of the vehicle is noisy due to vehicle horns, motorcycle
engines, air brakes of large vehicles, or other loud noises producing ultra-
sonic waves.
• There is another vehicle equipped with parking assist sensors in the
vicinity.
• A sensor is coated with a sheet of spray or heavy rain.
• The vehicle is equipped with a fender pole or wireless antenna.
• Towing eyelet is installed.
• A bumper or sensor receives a strong impact.
• The vehicle is approaching a tall or curved curb.
• In harsh sunlight or intense cold weather.
• A non-genuine Toyota suspension (lowered suspension etc.) is installed.
In addition to the examples above, there are instances in which, because of
their shapes, signs and other objects may be judged by the sensor to be
closer than they are.
The shape of the obstacle may prevent the sensor from detecting it. Pay

particular attention to the following obstacles:
• Wires, fences, ropes, etc.
• Cotton, snow and other materials that absorb sound waves
• Sharply-angled objects
• Low obstacles
• Tall obstacles with upper sections projecting outwards in the direction of
your vehicle
If a message is displayed
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P. 508
Corolla_TMMT_EE (OM12F04E)
4-5. Using the driving support systems
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