Lexus ES-300 2001 Manual page 26

11L003a
Since a transponder chip is not built in this flat key,
you cannot start the engine with this key. Use this
key to release the lock in case you accidentally lock
your keys inside the vehicle or trunk.
Insert your flat key in its key case as shown. We
recommend that you always carry this with you for
emergency use. Do not leave it in your vehicle.
NOTICE
D Do not let the key case become bent as the key
may fall out or become bent also.
D The flat key is designed for emergency use
only.
KEYS AND DOORS
9