Cadillac CT4 2020–2021 — technical service bulletin
Bulletin 21-NA-130 · NHTSA communication 11011711 · issued Nov 8, 2024
Technical service bulletin
communication type
Engine
component
2020–2021
model years
4
vehicle entries
Official summary
This service bulletin provides a repair procedure to correct a customer concern of Malfunction Indicator Lamp (MIL) Illuminated, DTC P31E8, P31DB, P31D4 and/or P31E2 Set.
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.