Mazda CX-3 Owner's Manual page 277

NOTE
In the following cases, the Blind Spot Monitoring (BSM) warning indication/warning
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light turns on and operation of the system is stopped. If the Blind Spot Monitoring
(BSM) warning indication/warning light remains illuminated, have the vehicle
inspected at an Authorised Mazda Dealer as soon as possible.
Some problem with the system including the Blind Spot Monitoring (BSM) warning
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indicator lights has occurred.
A large deviation in the installation position of a radar sensor (rear) on the vehicle
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has occurred.
There is a large accumulation of snow or ice on the rear bumper near a radar sensor
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(rear).
Driving on snow-covered roads for long periods.
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The temperature near the radar sensors becomes extremely hot due to driving for
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long periods on slopes during the summer.
The battery voltage has decreased.
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When Driving
i-ACTIVSENSE
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