TC and CG Terminal Circuit [08/2013 - ]: Wiring Diagram
WARNING: This page is about a different car, the 2014 Lexus ES 300h. However, it is still accessible from the selected car via links, so may be relevant.
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HINT:
When the warning lights blink without terminals TC and CG connected, a ground short in the wiring of terminal TC of the DLC3 or an internal ground short in one or more ECUs is suspected.