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: Rear door speaker inspection
1. Inspect for resistance between the rear door speaker terminals using an ohmmeter. If not as specified, replace the rear door speaker. 2. To verify that the rear door speaker outputs sound, apply voltage to the rear door speaker and release using a 1.5-V battery. If not outputs ...

Mazda 6 Service Manual: Filament inspection
1. Turn the ignition switch to ON position. 2. Turn the rear window defroster switch on. Caution Directly touching the rear window defroster filament with the lead of the voltmeter will damage it. Wrap aluminum foil around the end of the lead and test the filament by touching it with the ...