Lexus GS300 1998 Owner's Manual page 271

STARTING AND DRIVING
"START" – Starter motor on. The key will return to the
"ON" position when released.
For starting tips, see page 261.
"ON" – Engine on and all accessories on.
This is the normal driving position.
NOTICE
Do not leave the key in the "ON" position if the engine is
not running. The battery will discharge and the
electronic ignition system could be damaged.
"ACC" – Accessories such as the radio operate, but the
engine is off.
If you leave the key in the "ACC" or "LOCK" position and
open the driver's door, a buzzer will remind you to remove the
key.*
NOTE: *The volume or interval of beep sound can be
changed. Ask your Lexus dealer for details.
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