Wheel Electronics System (Tire Pressure Monitoring System), Siemens

WARNING: This page does not describe the selected car, but rather 9 other vehicles, including the 2018 Audi S6, 2018 Audi A6 Quattro, 2018 Audi A6, 2017 Audi S6, and 2017 Audi A6 Quattro. However, it is still accessible from the selected car via links, so may be relevant.

WARNING:

If tire sealant was used, then the wheel electronics on that particular wheel must be replaced.

The Siemens wheel electronics does not have a microencapsulated screw.
A union nut holds the wheel electronics in place inside the rim
The metal valve body serves as an antenna.
The connection between the metal valve body to the wheel electronics must not get damaged.

WARNING:

Counterhold the metal valve from the back by hand when pressing the wheel electronics into the bed on the rim. The connection between the metal valve to the wheel electronics must not get interrupted or damaged. Damaged wheel electronics must be replaced.

-- Press the wheel electronics into the bed.

-- Tighten the wheel electronics to the metal valve with the union nut