Caution
Turn the collar while applying force in the axial direction.

Clutch disc inspection
FlywheelMazda 6 Service Manual: Dtc c1955, c1956
Caution
When attaching the tester lead to the DSC HU/CM connector the SST
(49 G066 004) must be used.
Diagnostic procedure
...
Mazda 6 Service Manual: Driver-side air bag module removal/installation
Warning
Handling the air bag module improperly can accidentally deploy the
air bag module, which may seriously injure you. Read AIR BAG SYSTEM SERVICE
WARNINGS before handling the air bag module. (See SERVICE WARNINGS.)
Due to the adoption of 2-step deployment control in both the
driv ...