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: Mazda Radar Cruise Control (MRCC) (Some models)
The Mazda Radar Cruise Control (MRCC) system is designed to maintain headway
control*1 according to the vehicle speed using a radar sensor (front) to detect
the distance to a vehicle ahead, and by presetting the vehicle speed between 30
km/h (19 mph) and 145 km/h (90 mph), the driver is freed ...
Mazda 6 Service Manual: Advisory messages
You'll find several Warnings, Cautions, Notes, Specifications and Upper
and Lower Limits in this manual.
Warning
A Warning indicates a situation in which serious injury or death
could result if the warning is ignored.
Caution
A Caution indicates a situation in which damage to ...