Circuit/System Description
WARNING: This page is about a different car, the 2020 Cadillac CT4. However, it is still accessible from the selected car via links, so may be relevant.
The K73 Telematic Control Module receives information from the Cellular/GPS antenna element which is part of the T4P High Frequency Antenna located on the outside of the vehicle. The Cellular/GPS antenna element is connected to the K73 Telematic Control Module via a shielded coaxial cable. The K73 Telematic Control Module supplies 5 V through the coax cable to power the internal antenna amplifier.