Interior Light Auto Cut Circuit [08/2013 - ]: Description
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.
When the auxiliary battery saving function operates, the main body ECU (multiplex network body ECU) controls the operation of the solid-state relay, that is built into the roof console box assembly, to turn off the interior lights.