1. Verify that the joint shaft is not twisted or cracked.
2. Turn the joint shaft by hand and verify that the bearing rotates smoothly and freely.

Drive shaft
Joint shaft removal/installationMazda 6 Service Manual: Wheel hub, hub spindle pre-inspection
Wheel Bearing Play Inspection
1. Position a dial indicator against the wheel hub.
2. Push and pull the wheel hub by hand in the axial direction and measure the
wheel bearing play.
Maximum wheel bearing play
0.05 mm {0.002 in}
3. If the bearing play exceeds the specification, replace a ...
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 ...