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: Indication/Indicator Lights
These lights turn on or flash to notify the user of the system operation status
or a system malfunction.
*Some models.
*1 The light turns on when the ignition is switched on for an operation check,
and turns off a few seconds later or when the engine is started. If the light does
not t ...
Mazda 6 Service Manual: No.6 windshield fogged
When performing an asterisked (*) troubleshooting inspection, shake the
wiring harness and connectors while doing 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 and wir ...