To use the vanity mirror, lower the sunvisor.
If your vehicle is equipped with a vanity mirror light, it will illuminate when you open the cover.
To prevent the battery from being discharged, the vanity mirror will only illuminate in the tilt range shown in the figure.

Sunvisors
Interior LightsMazda 6 Owners Manual: Front buckle removal/installation
1. Perform the following procedure for vehicles with seat belt warning.
(1) Disconnect the negative battery cable.
(2) Remove the front seat.
(3) Disconnect the buckle switch connector.
2. Perform the following procedure for vehicles without seat belt warning.
(1) Remove the console.
...
Mazda 6 Owners Manual: Relay inspection
Relay Type
Four-terminal
Type A
1. Remove the relay.
2. Inspect for continuity between the relay terminals using an ohmmeter.
If not as specified, replace the relay.
Type B
1. Remove the relay.
2. Inspect for continuity between the relay terminals using an ohmmeter.
If not as ...