If your vehicle rapidly closes in on the vehicle ahead because the vehicle applies the brakes suddenly while you are traveling in headway control, the warning sound activates and the brake warning is indicated in the display. Always verify the safety of the surrounding area and depress the brake pedal while keeping a safer distance from the vehicle ahead.
Additionally, always keep a safer distance from the vehicles behind you.

Mazda Radar Cruise Control (MRCC) Display Indication
Setting the SystemMazda 6 Owners Manual: Mounting the Spare Tire
1. Remove dirt and grime from the mounting surfaces of the wheel and hub, including
the hub bolts, with a cloth.
WARNING
Make sure the mounting surfaces of the wheel, hub and lug nuts are clean
before changing or replacing tires: When changing or replacing a tire, not
removing dirt and gri ...
Mazda 6 Owners Manual: Replacing a Tire
WARNING
Always use tires that are in good condition: Driving with worn tires
is dangerous. Reduced braking, steering, and traction could result in an accident.
Replace all four tires at the same time: Replacing just one tire
is dangerous. It could cause poor handling and poor braking resulting ...