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: Limitations to SRS Air Bag
In severe collisions such as those described previously in "SRS Air Bag Deployment Criteria", the applicable SRS air bag equipment will deploy. However, in some accidents, the equipment may not deploy depending on the type of collision and its severity. Limitations to front/near front collision ...

Mazda 6 Service Manual: Electrical parts
Battery cable Before disconnecting connectors or removing electrical parts, disconnect the negative battery cable. Wiring Harness To remove the wiring harness from the clip in the engine room, pry up the hook of the clip using a flathead screwdriver. ...