TSB: Some 2017 ? 2018 model year Highlander and Sienna, 2018 model year Camry, and 2019 model year Avalon vehicles with and without the stop and start feature may exhibit a flex lock-up concern and MIL ON with Diagnostic Trouble Codes (DTCs) P07407E and/or P27567F. Vehicles that have experienced a delay in engagement from R to D will experience flex lock-up concerns from loss of solenoid pressure. The Engine Control Module (ECM) (SAE term: Powertrain Control Module/PCM) logic has been modified to reduce the possibility of this condition. Follow the Repair Procedure in this bulletin to address this condition.