DTC U1156-87: Lost Communication with TCM (ch2) Missing Message [09/2023 - ]: Wiring Diagram
WARNING: This page is about a different car, the 2024 Lexus TX 500h. However, it is still accessible from the selected car via links, so may be relevant.
Refer to the wiring diagram for TCM Power Source Circuit.
Refer to TCM Power Source Circuit [09/2023 - ]