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

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Mazda 6 Service Manual: Service cautions
HANDLING INSUFFICIENT REFRIGERANT LEVEL If an insufficient refrigerant level is detected at troubleshooting, do not charge (add) the refrigerant. Because an accurate amount of refrigerant cannot be determined from the pressure indicated on the manifold gauge, never charge the refrigeran ...

Mazda 6 Service Manual: Electrical troubleshooting tools
Jumper wire A jumper wire is used to create a temporary circuit. Connect the jumper wire between the terminals of a circuit to bypass a switch. Caution Do not connect a jumper wire from the power source line to a body ground. This may cause burning or other damage to wiring harnesse ...