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: Multiplex communication system
Outline
In case the controller area network (CAN) system is malfunctioning, read
the DTCs of the following modules, using the SST (WDS or equivalent) to
determine the malfunctioning system.
- PCM
- DSC HU/CM (with DSC)
- ABS (ABS/TCS) HU/CM (with ABS (ABS/TCS)
- Instrument clus ...
Mazda 6 Service Manual: Interior
Front
Rear
...