Service bulletins for the 2021 Cadillac XT4
A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.
684 on file from NHTSA, as of 2026-10-19.
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Only bulletins with component: Evaporative emissions are shown. Show all
| 21NA124 | 2021-07-19. Service bulletin. FUEL SYSTEM, GASOLINE:STORAGE:EVAPORATIVE EMISSIONS:CANISTER. This service bulletin provides diagnostic tips/steps on testing for possible EVAP leaks in the system to correct a customer concern of an MIL Illuminated with DTCs P0442 and/or P0455 Set. |
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The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.