Cadillac 2012 CTS Owner's Manual page 268

9-18 Driving and Operating
C (ON/RUN): This position is for
driving. It is the position the ignition
switch returns to after the engine
starts, and the key is released. This
position can also be used for
service and diagnostics, and to
verify the proper operation of the
malfunction indicator lamp as may
be required for emission inspection
purposes.
To shift the transmission out of
P (Park), the ignition key has to be
in ACC/ACCESSORY or ON/RUN.
The battery could be drained if the
key is left in the ACC/ACCESSORY
or ON/RUN position with the engine
off. The vehicle might not start if the
battery is allowed to drain for an
extended period of time.
D (START): This position starts the
engine. When the engine starts,
release the key. The ignition switch
returns to ON/RUN for driving.
A warning tone will sound when the
driver door is opened, the ignition is
in ACC/ACCESSORY or LOCK/
OFF, and the key is in the ignition.
Key Lock Release
Vehicles with an automatic
transmission are equipped with an
electronic key lock release system.
The key lock release is designed to
prevent ignition key removal unless
the shift lever is in P (Park).
The key lock release is always
functional except in the case of an
uncharged or low voltage (less than
9 volt) battery. If the vehicle has an
uncharged battery or a battery with
low voltage, try charging or jump
starting the battery. See
If charging or jump starting the
battery does not work, locate the
hole below the ignition lock. Insert a
flat bladed tool or another key from
the key chain into the opening.
When the lever can be felt, actuate
the lever away from the driver, and
remove the key from the ignition.
Ignition Positions
(Keyless Access)
The ignition control knob can be
turned to four different positions.
To shift out of P (Park), the ignition
must be in ON/RUN or ACC/
ACCESSORY and the regular brake
pedal must be applied.
.