The direction the vehicle is moving is displayed while the vehicle is being driven.

Cruise Control Set Vehicle Speed Display (Some models)
Warning (Display Indication)Mazda 6 Owners Manual: Contact Authorized Mazda Dealer and Have Vehicle Inspected
If any of the following warning lights or the indicator light turns on/flashes,
the system may have a malfunction. Contact an Authorized Mazda Dealer to have your
vehicle inspected.
...
Mazda 6 Owners Manual: To Resume Cruising Speed at More Than 25 km/h (16 mph)
If some other method besides the OFF/ CANCEL switch was used to cancel cruising
speed (such as applying the brake pedal) and the system is still activated, the
most recent set speed will automatically resume when the RESUME/
switch is pressed.
If vehicle speed is below 25 km/h (16 mph), incre ...