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: Installation of radio system
If a radio system is installed improperly or if a high-powered type is used, the CIS and other systems may be affected. When the vehicle is to be equipped with a radio, observe the following precautions: Install the antenna at the farthest point from control modules. Install the antenna fe ...

Mazda 6 Service Manual: Shift-Lock Override
If the selector lever will not move from P using the proper shift procedure, continue to hold down the brake pedal. 1. Remove the shift-lock override cover using a cloth-wrapped flat head screwdriver. 2. Insert a screwdriver and push it down. 3. Press and hold the lock-release button. 4. Mov ...