Mazda 6 Service Manual: No.20 noise occurs at idle when vehicle is stopped in all positions/ranges

No.19 excessive shift shock on torque converter clutch (tcc)

No.21 noise occurs at idle when vehicle is stopped in d, s, l ranges, or in r position

Other materials:

Mazda 6 Service Manual: Front combination light removal/installation
Caution Incorrect servicing of the discharge headlights could result in electrical shock. Before servicing the discharge headlights, always refer to the Discharge headlight service warnings. (See DISCHARGE HEADLIGHT SERVICE WARNINGS) Note When the ignition switch is turned to ON, ...

Mazda 6 Service Manual: Direct Mode
Direct mode can be used for temporarily switching gears by operating the steering shift switch while the vehicle is being driven with the selector lever in the D range. While in direct mode, the D and M indication illuminate and the gear position in use is illuminated. Direct mode is canceled ...