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

Taking Action
Message Indicated on DisplayMazda 6 Owners Manual: Locking, Unlocking with Door- Lock Knob
Operation from inside
To lock any door from the inside, press the door-lock knob.
To unlock, pull it outward. This does not operate the other door locks.
NOTE
The red indication can be seen when the door-lock knob is unlocked.
Operation from outside
To lock the rear and front passenger doo ...
Mazda 6 Owners Manual: Crash zone sensor removal/installation
Warning
Handling the crash zone sensor improperly can accidentally deploy the air bag
module and pre-tensioner seat belt, which may seriously injure you. Read AIR BAG
SYSTEM SERVICE WARNINGS before handling the crash zone sensor. (See SERVICE
WARNINGS.)
1. Turn the ignition switch to LO ...