Hyundai IONIQ Hybrid 2017–2019 — technical service bulletin
Bulletin 20-FL-012H · NHTSA communication 10185450 · issued Dec 16, 2020
Technical service bulletin
communication type
Engine and Engine Cooling
component
2017–2019
model years
5
vehicle entries
Official summary
This bulletin provides information related to the Engine Control Module (ECM) software logic update for DTC P0128 â Coolant thermostat - Coolant temp Below thermostat regulating Temperatureâ . There is no drivability issue with this DTC.
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.