Honda Accord 2017–2024 — technical service bulletin
Bulletin ATI&12022024909 · NHTSA communication 11011792 · issued Dec 3, 2024
Technical service bulletin
communication type
Engine
component
2017–2024
model years
14
vehicle entries
Official summary
Dealer Message - American Honda Motor Co., Inc. (AHM) is searching for certain 2018-2024 Accord 1.5Ls, 2021-2024 Civics 1.5Ls, 2023-2024 CR-Vs 1.5Ls, and 2017 Fits with customer complaint of Check Engine Light (CEL) on with DTC P0420 [Catalyst System Efficiency Below Threshold] stored. To better understand the cause of this condition, AHM would like to specific parts from the vehicle prior to you attempting a repair of any kind.
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.