Audi A4 2017–2018 — technical service bulletin
Bulletin DC_91CD · NHTSA communication 10217919 · issued Aug 9, 2022
Technical service bulletin
communication type
Equipment
component
2017–2018
model years
12
vehicle entries
Official summary
3G Turndown (91CD) Activation Support
Vehicles covered
What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.