The mirror defoggers defrost the outside mirrors.
The mirror defoggers operate in conjunction with the rear window defogger.
To turn on the mirror defoggers, switch the ignition ON and press the rear window defogger switch.
Manual Climate Control

Fully Automatic Climate Control

Rear Window Defogger
HornMazda 6 Owners Manual: Radar Sensors (Rear) (Some models)
Your vehicle is equipped with radar sensors (rear). The following systems also
use the radar sensors (rear).
Blind Spot Monitoring system (BSM)
Rear Cross Traffic Alert (RCTA)
The radar sensors (rear) function by detecting the radio waves reflected off
a vehicle approaching from the rea ...
Mazda 6 Owners Manual: Dtc c1955, c1956
Caution
When attaching the tester lead to the DSC HU/CM connector the SST
(49 G066 004) must be used.
Diagnostic procedure
...