Chevrolet 2005 Impala, Owner'S Manual, Page: 86 / 392

Automatic Transaxle Operation
Your automatic transaxle may have a shift lever on the
steering column or on the console between the seats.
There is also a display, like the graphic above, located
on the instrument panel cluster that will indicate the
gear the vehicle is in.
Maximum engine speed is limited on automatic transaxle
vehicles while you are in PARK (P) or NEUTRAL (N)
to protect driveline components from improper operation.
There are several different positions for your shift lever.
PARK (P): This position locks your front wheels. It is
the best position to use when you start your engine
because your vehicle cannot move easily.
{
CAUTION:
It can be dangerous to get out of your vehicle if
the shift lever is not fully in PARK (P) with the
parking brake firmly set. Your vehicle can roll. If
you have left the engine running, the vehicle
can move suddenly. You or others could be
injured. To be sure your vehicle will not move,
even when you are on fairly level ground, use
the steps that follow. If you are pulling a trailer,
see Towing a Trailer on page 4-36.
Make sure the shift lever is fully in PARK (P) before
starting the engine. Your vehicle has an automatic
transaxle shift lock control system. You must fully apply
your regular brakes before you can shift from PARK (P)
while the ignition is in ON. If you cannot shift out of
PARK (P), ease pressure on the shift lever by pushing it
all the way into PARK (P) while keeping the brake
pedal pushed down. Release the shift lever button if you
have a console shift. Then move the shift lever out of
PARK (P). See Shifting Out of Park (P) on page 2-25.
2-20