Cadillac XT4 2019–2022 — technical service bulletin
Bulletin 21NA127 · NHTSA communication 10214208 · issued Jan 21, 2022
Technical service bulletin
communication type
Electrical System
component
2019–2022
model years
11
vehicle entries
Official summary
This technical bulletin provides repair information to correct a customer concern of Head Up Display (HUD) Blank, Non-Responsive to Brightness, Aim, or Page Controls, DTC U1518 Set.
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.