Circuit Description
WARNING: This page is about a different car, the 2002 Lexus LX 470. However, it is still accessible from the selected car via links, so may be relevant.
terminal No. 4 (TRLY) of the wireless door lock ECU outputs the signal once when pressing the LOCK switch of the transmitter and twice when pressing the UNLOCK switch and then makes the taillight come to light. See Fig 1.