Porsche Cayenne 2021–2023 — technical service bulletin
Bulletin No. 155-21-4 · NHTSA communication 10227388 · issued Nov 28, 2022
Technical service bulletin
communication type
Equipment
component
2021–2023
model years
6
vehicle entries
Official summary
Technical information for WML0 - retrofitting loudspeaker booster
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.