Circuit Description
WARNING: This page is about a different car, the 2004 Lexus ES 330. However, it is still accessible from the selected car via links, so may be relevant.
When the theft deterrent system is operating, the relay in the ECU turns ON and OFF in a cycle of approximately 0.2 seconds, causing the theft deterrent horn to blow (See Figure. In this condition, if any of the following operations has been performed, the relay in the ECU turns OFF, thus the theft deterrent horn stops blowing.