Circuit Description
WARNING: This page is about a different car, the 2003 Lexus ES 300 and 2002 Lexus ES 300. However, it is still accessible from the selected car via links, so may be relevant.
When the anti-theft system is operating, the relay in the ECU turns ON and OFF in a cycle of approximately 0.2 seconds. See Fig 1. In this condition, if any of the following operation has been done, the relay in the ECU turns OFF, thus the anti-theft horn stops blowing.