Genesis G80 2021–2026 — technical service bulletin
Bulletin 26-HA-002G TSB · NHTSA communication 11033845 · issued Jun 10, 2026
Technical service bulletin
communication type
Engine
component
2021–2026
model years
18
vehicle entries
Official summary
Some Genesis vehicles (listed below) equipped with Lambda-III 3.5T-GDI engines may exhibit reduced heater performance due to engine coolant deposits clogging the heater core. This bulletin provides instructions to verify the concern and to replace the front and rear heater core (if applicable).
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.