Mazda 3 2018 Owner's Manual page 233

In the following cases, it may be difficult to view the illumination/flashing of the Blind

Spot Monitoring (BSM) warning indicator lights equipped on the door mirrors.
Snow or ice adheres to the door mirrors.

The front door glass is fogged or covered in snow, frost or dirt.

Turn off the RCTA system while pulling a trailer or while an accessory such as a bicycle

carrier is installed to the rear of the vehicle. Otherwise, the radio waves emitted by the
radar will be blocked causing the system to not operate normally.
Mazda3_8GE4-EA-17F_Edition1
When Driving
i-ACTIVSENSE
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2017-4-7 11:59:21