Lexus RX300 2003 Owner's Manual page 30

11R055
D When starting the engine, do not use the key with
other transponder keys around (including the flat key
and keys of other vehicles) and do not press other
key plates against the key grip. Otherwise the engine
may not start, or may stop soon after it starts. If this
happens, remove the key once and then insert it
again after taking off other transponder keys
(including the flat key and keys of other vehicles)
from the ring or while gripping or covering them with
your hand to start the engine.
11R091
D Do not bend the key grip or flat key.
D Do not cover the key grip or flat key with any material
that cuts off electromagnetic waves.
D Do not knock the key or flat key hard against other
objects.
D Do not leave the key or flat key exposed to high
temperatures for a long period, such as on the
dashboard and hood under the direct sunlight.
D Do not put the key or flat key in water or wash it in an
ultrasonic washer.
D Do not use the key or flat key with electromagnetic
materials.
2003 RX300 from Aug. 02' Prod. (OM48442U)