Some variance occurs between the actual road and the displayed road. Such variance in distance perspective could lead to an accident. Note the following conditions that may cause a variance in distance perspective.
When the vehicle is tilted due to the weight of passengers and load
When the vehicle rear is lowered, the object displayed on the screen appears farther than the actual distance.

When there is a steep grade behind the vehicle
When there is a steep upgrade (downgrade) behind the vehicle, the object displayed on the screen appears farther (downgrade: closer) than the actual distance.

Three-dimensional object on vehicle rear
Because the distance guide lines are displayed based on a flat surface, the distance to the three-dimensional object displayed on the screen is different from the actual distance.

Rear View Monitor Operation
Picture Quality AdjustmentMazda 6 Owners Manual: Dsc on-board diagnosis
On-Board Diagnostic (OBD) Test Description
(See ABS (ABS/TCS) ON-BOARD DIAGNOSIS)
DTC Table
PID/DATA Monitor Table
Active Command Modes Table
...
Mazda 6 Owners Manual: Plastic Part Maintenance
When cleaning the plastic lenses of the lights, do not use gasoline, kerosene,
rectified spirit, paint, thinner, highly acidic detergents, or strongly alkaline
detergents. Otherwise, these chemical agents can discolor or damage the surfaces
resulting in a significant loss in functionalit ...