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: Woofer inspection
1. Inspect for continuity between the audio amplifier connector terminals and woofer connector terminals using an ohmmeter. If not as specified, replace the related wiring harnesses. 2. Verify that there is battery positive voltage at the woofer connector terminal A (4SD) or C (5HB) u ...

Mazda 6 Service Manual: Automatic Transaxle Controls
Various Lockouts: Indicates that you must depress the brake pedal and hold in the lock-release button to shift (The ignition must be switched ON). Indicates the shift lever can be shifted freely into any position. Indicates that you must hold in the lock-release button to shift. N ...