Lexus ES-300 2001 Manual page 28

KEYS AND DOORS
11E022
D When starting the engine, do not use the key
with other transponder keys around (including
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 keys of other
vehicles) from the ring or while gripping or
covering them with your hand to start the
engine.
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