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: Fuel pump unit inspection
Caution
It is normal to hear the fuel pump operating when the ignition
switch is turned to the ON position.
Note
To improve startability, the fuel pump control operates the fuel
pump unit when the ignition switch is turned to the ON position. Due to
this, fuel pressure is rapidly ...
Mazda 6 Owners Manual: Inspection of dtcs for operation mode
Note
The cruise set indicator light will illuminate for 3 seconds? when
operation mode is on.
If the cruise set indicator light does not illuminate for 3
seconds (Operation mode is not on)? the following may be the cause of the
malfunction:
- Cruise actuator ignition power suppl ...