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: Instrument cluster inspection
Speedometer Using the input/output check mode Inspect the speedometer by setting it in the input/output check mode DTC 12. Using a speedometer tester 1. Adjust the tire air pressure to the specification. 2. Using a speedometer tester, verify that the speedometer indication is within the allow ...

Mazda 6 Service Manual: Solenoid valve removal/installation
1. Disconnect the negative battery cable. 2. Remove the under cover. 3. Remove the control valve body. (See CONTROL VALVE BODY REMOVAL.) 4. Remove the solenoid valve(s). 5. Apply ATF to a new O-ring and install it on the solenoid valve. 6. Install the solenoid valve in the control valve body. ...