TC and CG Terminal Circuit: Wiring Diagram
WARNING: This page is about a different car, the 2008 Lexus IS F. However, it is still accessible from the selected car via links, so may be relevant.
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
HINT.
When each warning light stays blinking, a ground short in the wiring of terminal TC of the DLC3 or an internal ground short in each ECU is suspected.