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

Taking Action
Message Indicated on DisplayMazda 6 Owners Manual: Power brake unit removal/installation
1. Remove the master cylinder. (See MASTER CYLINDER REMOVAL/INSTALLATION.)
2. Remove the wiper arm. (See WINDSHIELD WIPER ARM AND BLADE
REMOVAL/INSTALLATION.)
3. Remove the cowl grille. (See COWL GRILLE REMOVAL/INSTALLATION.)
4. Remove the wiper motor. (See WINDSHIELD WIPER MOTOR REMOVAL/INSTAL ...
Mazda 6 Owners Manual: Seat warmer switch inspection
1. Remove the seat warmer switch.
2. Inspect for continuity between the seat warmer switch terminals using an
ohmmeter.
If not as specified, replace the seat warmer switch.
Drivers side
Passengers side
...