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: Dual proportioning valve inspection (without abs)
1. Connect the SSTs to the brake pipes as shown in the figure.
2. Bleed the air from the brake system.
3. Measure the fluid pressure of the master cylinder and the rear brake.
If not within the specification, replace the dual proportioning valve.
Fluid pressure
...
Mazda 6 Service Manual: Cruise actuator inspection
1. Disconnect the cruise actuator connector.
2. Measure the voltage, continuity and resistance at the cruise actuator
terminals as indicated below.
If not as specified, inspect the parts listed under Action.
If the parts and wiring harnesses are okay but the system still does not
work pr ...