Activating System

WARNING: This page is about a different car, the 2002 Lexus GS 430 and 2002 Lexus GS 300. However, it is still accessible from the selected car via links, so may be relevant.

The alarm sounds for 60 seconds if any of the following are operated:

Unlocking any door or trunk without using an ignition key or wireless remote control.
Opening the hood forcibly.
Reconnecting the battery.

If any door is unlocked during the alarm sounding, it's door is automatically locked.

To stop the alarm -

Unlock the door or trunk using an ignition key or wireless remote control.
Turn the ignition switch on.