Mazda 6 Service Manual: No.22 vibration concerns (engine)

No.21 engine noise

No.23 a/c does not work sufficiently

Other materials:

Mazda 6 Service Manual: Ignition switch inspection
1. Disconnect the negative battery cable. 2. Remove the column cover. (See COLUMN COVER REMOVAL/INSTALLATION) 3. Disconnect the ignition switch connectors. 4. Inspect for continuity between the ignition switch terminals using an ohmmeter. If not as specified, replace the ignition switch. ...

Mazda 6 Service Manual: Immobilizer System
The immobilizer system allows the engine to start only with a key the system recognizes. If someone attempts to start the engine with an unrecognized key, the engine will not start, thereby helping to prevent vehicle theft. If you have a problem with the immobilizer system or the key, consult ...