Hyundai Sonata 2020 — technical service bulletin
Bulletin Campaign T4N Dea · NHTSA communication 10172146 · issued Feb 11, 2020
Technical service bulletin
communication type
Electrical System
component
2020
model years
1
vehicle entries
Official summary
This service campaign provides information related to an ECM software update to revise the logic for DTC P0456: EVAP System Leakage Detected Very Small Leak.
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.