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

Taking Action
Message Indicated on DisplayMazda 6 Owners Manual: Generator inspection
Generator Warning Light
1. Verify that the battery is fully charged.
Charge if necessary.
2. Verify that the drive belt deflection/tension is correct. (See DRIVE BELT
INSPECTION.)
If not as specified, replace the drive belt.
3. Turn the ignition switch to ON and verify that the gene ...
Mazda 6 Owners Manual: Generator removal/installation
Warning
When the battery cables are connected, touching the vehicle body with
generator terminal B will generate sparks. This can cause personal injury, fire,
and damage to the electrical components. Always disconnect the battery negative
cables before performing the following operation.
...