Visual Characteristics Of Ceramic Brake Rotors
WARNING: This page does not describe the selected car, but rather 9 other vehicles, including the 2015 Audi S7, 2015 Audi RS 7, 2015 Audi A7 Quattro, 2014 Audi S7, and 2014 Audi RS 7. However, it is still accessible from the selected car via links, so may be relevant.
Checking threaded connectors on the brake rotor ring and brake rotor cup:
WARNING:
The brake rotor ring and the brake disc cup are attached to each other and must never be separated. Never loosen the threaded connector on the brake rotor cup.
The friction surface on a new brake rotor already has stress cracks made during the production process. These stress cracks are all different.
NOTE:
Stress cracks do not mean the ceramic brake rotor is faulty.
The stress cracks are somewhat visible and can be different from each other in strength.