Cadillac 2005 CTS - Manual (Page 93)

A (OFF): This is the only position in which you can
insert or remove the key. This position locks the ignition,
steering wheel and transmission. It is a theft-deterrent
feature.
B (ACCESSORY): This position allows you to use
things like the radio and the windshield wipers when
the engine is off. This position will allow you to turn off
the engine, but still turn the steering wheel.
C (ON): This position is for driving. If your vehicle
has an automatic transmission and you turn off
the engine, the transmission will lock. If you need to
shift the transmission out of PARK (P), the ignition
key has to be in ON.
D (START): This position starts the engine.
Key Release Button
(Manual Transmission)
The key cannot be
removed from the
ignition of manual
transmission vehicle
unless the key release
button is used.
To remove the key, do the following:
1. Turn the key to ACCESSORY.
2. Press and release the button and then turn
the key to OFF.
Do not hold the button in while turning the
key to OFF.
3. Pull the key straight out of the ignition switch.
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