This feature prevents all power windows from operating, except the driver's power window. Keep this switch in the locked position while children are in the vehicle.
Locked position (button depressed):
Only the driver's power window can be operated.
Unlocked position (button not depressed):
All power windows on each door can be operated.

NOTE
When the power window lock switch is in the locked position, the light on each power window switch, except for the driver's power window switch, turns off. The light may be difficult to see depending on the surrounding brightness.
Operating the Power Windows
Moonroof (Some models)Mazda 6 Owners Manual: Distance Recognition Support System (DRSS) (Some models)
The Distance Recognition Support System (DRSS) measures the distance between
your vehicle and a vehicle ahead using a radar sensor (front) while the vehicle
speed is about 30 km/h (19 mph) or faster, and if your vehicle approaches a vehicle
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Mazda 6 Owners Manual: Wheel hub, steering knuckle removal/installation
Caution
Performing the following procedures without first removing the ABS
wheel-speed sensor may possibly cause an open circuit in the harness if it
is pulled by mistake. Before performing the following procedures, remove the
ABS wheel-speed sensor (axle side) and fix it to an appropri ...