areas that vehicles can be detected in are outlined below TOYOTA AVALON 2021 Owners Manual (in English)

2644-5. Using the driving support systems
The BSM function uses radar sensors to detect vehicles that are trav-
eling in an adjacent lane in the area that is usually not reflected in the
outside rear view mirror (the blind spot), and advises the driver of the
vehicles existence via the outside rear view mirror indicator.
The areas that vehicles can be detected in are outlined below.
The range of the detection area is:
Approximately 1.6 ft. (0.5 m) to 11.5 ft. (3.5 m) from either side of
the vehicle
The area between the side of the vehicle and 1.6 ft. (0.5 m) from the side
of the vehicle cannot be detected.
Approximately 3.3 ft. (1 m) forward of the rear bumper
Approximately 9.8 ft. (3 m) from the rear bumper
Approximately 9.8 ft. (3 m) to 197 ft. (60 m) from the rear bumper
The greater the difference in speed between your vehicle and the
detected vehicle is, the farther away the vehicle will be detected,
causing the outside rear view mirror indicator to illuminate or flash.
BSM function
BSM function detection areas
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2694-5. Using the driving support systems
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Driving
The areas that vehicles can be detected in are outlined below.
To give the driver a more consistent time to react, the buzzer can alert
for faster vehicles from farther away.
Example:
■The RCTA function is operational when
●The RCTA function is turned on.
●The shift lever is in R.
●Vehicle speed is less than approximately 5 mph (8 km/h).
●Approaching vehicle speed is between approximately 5 mph (8 km/h) and
18 mph (28 km/h).
RCTA function detection areas
Approaching vehicleSpeedApproximate
alert distance
Fast18 mph (28 km/h)65 ft. (20 m)
Slow5 mph (8 km/h)18 ft. (5.5 m)
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