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: No.8 no cool air
When performing an asterisked (*) troubleshooting inspection, shake the
wiring harness and connectors while performing the inspection to discover
whether poor contact points are the cause of any intermittent malfunctions.
If there is a problem, check to make sure connectors, terminals ...
Mazda 6 Service Manual: System Operation
Make sure that the Lane-keep Assist System (LAS) & Lane Departure Warning System
(LDWS) OFF indicator light in the instrument cluster is turned off. When the Lane-keep
Assist System (LAS) & Lane Departure Warning System (LDWS) OFF indicator light is
turned on, press the switch and make ...