Toyota Highlander 2017–2018 — technical service bulletin
Bulletin T-SB-0001-18 Rev · NHTSA communication 10185780 · issued Dec 11, 2020
Technical service bulletin
communication type
Electrical System
component
2017–2018
model years
4
vehicle entries
Official summary
TSB: When completing a transaxle assembly replacement, Engine Control Module (ECM) (SAE term: Powertrain Control Module [PCM]) replacement, or ECM (PCM) reprogram, ensure the correct ECM (PCM) software is matched with the transaxle assembly hardware. Some 2017 ? 2018 model year Highlander and Sienna vehicles require different ECM (PCM) software based on the transaxle assembly hardware installed in the vehicle.
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.