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: Curtain Air Bags
The curtain air bags are mounted in the front and rear window pillars, and the roof edge along both sides. When the air bag crash sensors detect a side impact of greater than moderate force, the curtain air bag inflates quickly and helps to reduce injury mainly to the rear outboard passenger' ...

Mazda 6 Service 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. ...