Saturn 2007 Ion Owner's Manual page 106

R
(RUN): This is the position the switch returns to
after you start your engine and release the
switch. The switch stays in the RUN position when
the engine is running. But even when the ignition
is not running, you can use RUN to operate
your electrical accessories and to display some
warning and indicator lights.
The battery could be drained if you leave the key
in the ACC or RUN position with the engine
off. You may not be able to start your vehicle if
the battery is allowed to drain for an extended
period of time.
/
(START): This position starts the engine. When
the engine starts, release the key. The ignition
switch will return to RUN for normal driving.
A warning tone will sound if you open the driver's
door while in LOCK or ACC, when the key has not
been removed from the ignition.
106
Key In the Ignition
Never leave your vehicle with the keys inside, as it
is an easy target for joy riders or thieves. If you
leave the key in the ignition and park your vehicle,
a chime will sound, when you open the driver's
door. Always remember to remove your key from
the ignition and take it with you. This will lock
your ignition and transaxle. Also, always remember
to lock the doors.
The battery could be drained if you leave the key
in the ignition while your vehicle is parked.
You may not be able to start your vehicle after it
has been parked for an extended period of time.