Take the appropriate action and verify that the warning light turns off.

Taking Action
Message Indicated on DisplayMazda 6 Owners Manual: Seat Belt Extender
If your seat belt is not long enough, even when fully extended, a seat belt extender
may be available to you at no charge from your Authorized Mazda Dealer.
This extender will be only for you and for the particular vehicle and seat. Even
if it plugs into other seat belts, it may not hold in the ...
Mazda 6 Owners Manual: Tire Inflation Pressure
WARNING
Always inflate the tires to the correct pressure: Overinflation or
underinflation of tires is dangerous. Adverse handling or unexpected tire failure
could result in a serious accident.
Use only a Mazda-genuine tire valve cap: Use of a non-genuine part
is dangerous as the correct tire ...