Cadillac 2011 DTS Owner's Manual page 131

It is dangerous to get out of the vehicle if the shift
lever is not fully in P (Park) with the parking brake
firmly set. The vehicle can roll.
Do not leave the vehicle when the engine is
running unless you have to. If you have left the
engine running, the vehicle can move suddenly.
You or others could be injured. To be sure the
vehicle will not move, even when you are on fairly
level ground, always set the parking brake and
move the shift lever to P (Park). See Shifting Into
Park on page 3 30. If you are pulling a trailer,
see Towing a Trailer on page 5 26.
Make sure the shift lever is fully in P (Park) before
starting the engine. The vehicle has an automatic
transmission shift lock control system. You have to
fully apply the regular brakes before you can shift from
P (Park) while the ignition key is in ON/RUN. If you
cannot shift out of P (Park), ease pressure on the shift
lever. Push the shift lever all the way into P (Park) as
you maintain brake application. Then move the shift
lever into another gear. See Shifting Out of Park on
page 3 32.
Use this gear to back up.
Also use this gear to rock the vehicle back and forth
to get out of snow, ice or sand without damaging the
transmission. See If Your Vehicle is Stuck in Sand,
Mud, Ice, or Snow on page 5 17 for additional
information.
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