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: Tire Chains
Check local regulations before using tire chains. CAUTION Chains may affect handling. Do not go faster than 50 km/h (30 mph) or the chain manufacturer's recommended limit, whichever is lower. Drive carefully and avoid bumps, holes, and sharp turns. Avoid locked-wheel braking. Do not ...

Mazda 6 Service Manual: Warning Indication/Warning Lights
These lights turn on or flash to notify the user of the system operation status or a system malfunction. *1 The light turns on when the ignition is switched on for an operation check, and turns off a few seconds later or when the engine is started. If the light does not turn on or remai ...