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: Variable intake-air system (vis) control solenoid valve inspection (l3)
1. Remove the VIS control solenoid valve. (See INTAKE-AIR SYSTEM
REMOVAL/INSTALLATION.)
2. Inspect airflow between the ports under the following conditions.
If not as specified, replace the VIS control solenoid valve.
If as specified, carry out the Circuit Open/Short Inspection.
Circ ...
Mazda 6 Service Manual: Installation of radio system
If a radio system is installed improperly or if a high-powered type is used,
the CIS and other systems may be affected. When the vehicle is to be equipped
with a radio, observe the following precautions:
Install the antenna at the farthest point from control modules.
Install the antenna fe ...