Toyota Highlander 2020–2024 — technical service bulletin
Bulletin T-SB-0021-26 · NHTSA communication 11031158 · issued Mar 18, 2026
Technical service bulletin
communication type
Electrical System
component
2020–2024
model years
10
vehicle entries
Official summary
Some 2020 – 2024 model year Highlander and Highlander Hybrid vehicles may exhibit a condition in which the air conditioner does not cool due to a leak and/or corrosion in the rear underbody air conditioner tube and accessory assembly. The anti-corrosion material has been updated to reduce the possibility of this condition.
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.