Mazda Mazda3 2019 Owner's Manual page 261

NOTE
If a vehicle ahead is detected while travelling at a constant speed, the vehicle-ahead

indication is displayed and headway control is performed. Additionally, when a vehicle
ahead is no longer detected, the vehicle-ahead indication turns off and the system
switches back to travel at constant speed.
The lowest possible speed which can be set on the MRCC with Stop & Go function system

is 30 km/h (19 mph).
Headway control is not possible if the vehicle ahead is driving faster than your vehicle's

set speed. Adjust the system to the desired vehicle speed using the accelerator pedal.
How to set the distance-between-vehicles during headway control
The distance-between-vehicles can be set to 4 levels; Long, medium, short, and extremely
short distance.
The distance-between-vehicles is set to a shorter distance by pressing the CANCEL switch
down. The distance-between-vehicles is set to a longer distance by pressing the CANCEL
switch up.
Distance-between-vehicles guide‐
line
(at 80 km/h (50 mph) vehicle
speed)
Long (about 50 m (164 ft))
Medium (about 40 m (131 ft))
Indication on multi-information
display
When Driving
i-ACTIVSENSE
Indication on active driving dis‐
*1
play
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