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: Camera and Sensors
Forward Sensing Camera (FSC)
The Forward Sensing Camera (FSC) detects lane indications and recognizes headlights,
taillights and city lights during nighttime driving. In addition, it also detects
the vehicle ahead, pedestrians, or obstructions. The following systems also use
the Forward Sensi ...
Mazda 6 Service Manual: Starting the Engine
WARNING
Radio waves from the key may affect medical devices such as pacemakers:
Before using the key near people who use medical devices, ask the medical device
manufacturer or your physician if radio waves from the key will affect the device.
NOTE
The key must be carried because the key c ...