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: Brake pedal inspection
Brake Pedal Height Inspection
Verify that the distance from the carpet to the center of the upper surface
of the pedal pad is as specified.
Pedal height (reference value)
Brake Pedal Height Adjustment
1. Loosen locknut B and turn the bolt A until it does not contact the pedal.
2. Loosen l ...
Mazda 6 Owners Manual: Cruise actuator removal/installation
1. Disconnect the negative battery cable.
2. Remove in the order indicated in the table.
3. Install in the reverse order of removal.
Cover Removal Note
Unclamp the clips of the heater hoses at the front of the cover.
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