TSB: Some 2020 ? 2022 Highlander and Highlander Hybrid and 2021 ? 2022 Sienna Hybrid vehicles
may exhibit a MIL ON condition with Diagnostic Trouble Codes (DTCs) P0087 (Fuel Rail/System
Pressure ? Too Low) and/or P107A2A (Fuel Rail Pressure Sensor (Low) Signal Stuck in Range)
present. This condition may occur when the vehicle is operated at high altitude and high
temperature; typically, above 3,300 feet (1,000 meters) and ambient temperature above 85°F
(30°C). The Engine Control Module (ECM) (SAE term: Powertrain Control Module/PCM) logic has
been modified to reduce the possibility of this condition occurring. Follow the Repair Procedure in
this bulletin to address this condition