Lexus RX300 Manual page 144

If any door is unlocked and the ignition key is not in the ignition
switch during the alarm sounding, its door is automatically locked.
To stop the alarm: Use either of the following methods.
D Unlock the door using an ignition key or wireless remote control.
D Turn the ignition switch on.
Testing the system
1. Open all the windows.
2. Set the system as described above.
The front doors should be locked with the ignition key or wireless
remote control. Be sure to wait until the indicator light starts
flashing.
3. Unlock one of the doors from the inside.
The system should activate the alarm.
4. Unlock any of the doors with a key or the wireless remote
control to cancel the system.
5. Repeat this operation for the other doors and hood.
When testing the hood, also check that the system is activated when
the battery terminal is disconnected and then reconnected.
If the system does not work properly, have it checked by your Lexus
dealer.
NOTICE
Disconnecting the battery may result in the erasure of
information you have set in the computer memory. After
reconnecting the battery, check that the memorized data has
been retained. If it has been erased, input it into the computer
once more.
THEFT DETERRENT
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