WARNING: This page is about a different car, the 2023 Audi SQ8, 2023 Audi RS Q8, and 2023 Audi Q8. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Removing Inner Insulation
Courtesy of AUDI
-- Push the antenna wire -2- in the mount -1- all the way into the tool head.