
Black plate (18,1)Chevrolet Impala Owner Manual (GMNA-Localizing-U.S./Canada-7576026) -
2015 - crc 2nd edition - 8/21/14
9-18 Driving and Operating
ventilation fan and 12-volt power
outlets, as well as to display some
warning and indicator lights. 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. The transmission is also
unlocked in this position.
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 restart if
the battery is allowed to drain for an
extended period of time.
4 (START):This position starts the
engine. When the engine starts,
release the key. The ignition switch
will return to ON/RUN for normal
driving.
A warning tone sounds when the
driver door is opened when the
ignition is still in ACC/ACCESSORY
and the key is in the ignition. If the
ignition becomes difficult to turn,
see Keys on page 2-1.Starting the Engine
Move the shift lever to P (Park) or
N (Neutral). To restart the engine
when the vehicle is already moving,
use N (Neutral) only.
{Caution
Do not try to shift to P (Park) if the
vehicle is moving. If you do, you
could damage the transmission.
Shift to P (Park) only when the
vehicle is stopped.
{Caution
If you add electrical parts or
accessories, you could change
the way the engine operates. Any
resulting damage would not be
covered by the vehicle warranty.
See Add-On Electrical Equipment
on page 9-63. Starting Procedure (Key Access)
1. With your foot off the accelerator
pedal, turn the ignition key to
START. When the engine starts,
let go of the key. The idle speed
will go down as the engine
warms. Do not race the engine
immediately after starting it.
Allow the oil to warm up and
lubricate all moving parts.
{Caution
Cranking the engine for long
periods of time, by returning the
ignition to the START position
immediately after cranking has
ended, can overheat and damage
the cranking motor, and drain the
battery. Wait at least 15 seconds
between each try, to let the
cranking motor cool down.
2. If the engine does not start after five to 10 seconds, especially in
very cold weather (below −18°C
or 0°F), it could be flooded with

Black plate (19,1)Chevrolet Impala Owner Manual (GMNA-Localizing-U.S./Canada-7576026) -
2015 - crc 2nd edition - 8/21/14
Driving and Operating 9-19
too much gasoline. Push the
accelerator pedal all the way to
the floor and hold it there as you
hold the key in START for a
maximum of 15 seconds. Wait at
least 15 seconds between each
try, to allow the cranking motor
to cool. When the engine starts,
let go of the key and accelerator.
If the vehicle starts briefly but
then stops again, repeat the
procedure. This clears the extra
gasoline from the engine. Do not
race the engine immediately
after starting it. Operate the
engine and transmission gently
until the oil warms up and
lubricates all moving parts.Starting Procedure (Keyless
Access)
1. With the Keyless Access
system, the Remote Keyless
Entry (RKE) transmitter must be
in the vehicle. Press the
ENGINE START/STOP button
with the brake pedal applied.
When the engine begins
cranking, let go of the button.
The idle speed will go down as
the engine gets warm. Do not
race the engine immediately
after starting it.
If the RKE transmitter is not in
the vehicle, if there is
interference, or the RKE battery
is low, a Driver Information
Center (DIC) message will
display. See Driver Information
Center (DIC) on page 5-25.{Caution
Cranking the engine for long
periods of time, by returning the
ignition to the START position
immediately after cranking has
ended, can overheat and damage
the cranking motor, and drain the
battery. Wait at least 15 seconds
between each try, to let the
cranking motor cool down.
2. If the engine does not start after five to 10 seconds, especially in
very cold weather (below −18°C
or 0°F), it could be flooded with
too much gasoline. Try pushing
the accelerator pedal all the way
to the floor and holding it there
as you press the ENGINE
START/STOP button, for up to a
maximum of 15 seconds. Wait at
least 15 seconds between each
try, to allow the cranking motor
to cool down. When the engine
starts, let go of the key or button,
and the accelerator. If the

Black plate (20,1)Chevrolet Impala Owner Manual (GMNA-Localizing-U.S./Canada-7576026) -
2015 - crc 2nd edition - 8/21/14
9-20 Driving and Operating
vehicle starts briefly but then
stops again, do the same thing.
This clears the extra gasoline
from the engine. Do not race the
engine immediately after starting
it. Operate the engine and
transmission gently until the oil
warms up and lubricates all
moving parts.
Stop/Start System
{Warning
Exiting the vehicle without first
shifting into P (Park) may cause
the vehicle to move. You or others
may be injured. Because the
vehicle has the auto engine stop/
start feature, the vehicle's engine
might seem to be shut off;
however, once the brake pedal is
released, the engine will start up
again.
Shift to P (Park) and turn the
ignition to LOCK/OFF, before
exiting the vehicle.If equipped with the 2.5L L4 Engine,
the vehicle has a fuel saving stop/
start system to shut off the engine to
help conserve fuel.
Auto Engine Stop/Start
When the brakes are applied and
the vehicle is at a complete stop,
the engine may turn off. When
stopped, the tachometer displays
AUTO STOP. See
Tachometer on
page 5-12. When the brake pedal is
released or the accelerator pedal
pushed, the engine will restart.
Auto stop may be deactivated if:
.A minimum vehicle speed is not
reached.
.The engine or transmission is
not at the required operating
temperature.
.The outside temperature is not
in the required operating range,
typically below -10°C (14°F) or
above 50°C (122°F).
.The shift lever is in any gear
other than D (Drive).
.The battery charge is low.
.The interior comfort level has not
reached the required level for
the climate control system or
defog settings. Use the eco
(green indicator on) air
conditioning mode for better
efficiency. See Dual Automatic
Climate Control System on
page 8-3.
.The auto stop time is greater
than two minutes.
Engine Heater
The engine coolant heater,
if equipped, can help in cold
weather conditions at or below −18°
C (0°F) for easier starting and better
fuel economy during engine
warm-up. Plug in the coolant heater
at least four hours before starting
the vehicle. An internal thermostat
in the plug end of the cord will
prevent engine coolant heater
operation at temperatures above
−18°C (0°F).

Black plate (22,1)Chevrolet Impala Owner Manual (GMNA-Localizing-U.S./Canada-7576026) -
2015 - crc 2nd edition - 8/21/14
9-22 Driving and Operating
4. Before starting the engine, besure to unplug and store the
cord as it was before to keep it
away from moving engine parts.
The length of time the heater should
remain plugged in depends on
several factors. Ask a dealer in the
area where you will be parking the
vehicle for the best advice on this.
Retained Accessory
Power (RAP)
These vehicle accessories can be
used for up to 10 minutes after the
engine is turned off:
.Audio System
.Power Windows
.Sunroof (if equipped)
These features continue to work up
to 10 minutes after the ignition is
turned to LOCK/OFF.
The power windows and sunroof will
work until any door is opened.
The radio continues to work until the
driver door is opened. All these features operate when the
key is in ON/RUN or ACC/
ACCESSORY.
Shifting Into Park
1. Hold the brake pedal down and
set the parking brake. See
Parking Brake on page 9-29.
2. Move the shift lever into P (Park) by holding in the button on the
shift lever and pushing the shift
lever all the way toward the front
of the vehicle.
3. Turn the ignition key to LOCK/OFF.
4. If equipped, remove the key and take it with you. If you can leave
the vehicle with the ignition key
in your hand, the vehicle is in
P (Park).
Leaving the Vehicle with the
Engine Running
{Warning
It can be dangerous to leave the
vehicle with the engine running.
It could overheat and catch fire.
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. 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 9-22.

Black plate (23,1)Chevrolet Impala Owner Manual (GMNA-Localizing-U.S./Canada-7576026) -
2015 - crc 2nd edition - 8/21/14
Driving and Operating 9-23
If you have to leave the vehicle with
the engine running, be sure the
vehicle is in P (Park) and the
parking brake is firmly set before
you leave it. After you have moved
the shift lever into P (Park), hold the
regular brake pedal down. Then,
see if you can move the shift lever
away from P (Park) without first
pressing the button.
If you can, it means that the shift
lever was not fully locked in
P (Park).
Torque Lock
Torque lock is when the weight of
the vehicle puts too much force on
the parking pawl in the
transmission. This happens when
parking on a hill and shifting the
transmission into P (Park) is not
done properly, then it is difficult to
shift out of P (Park). To prevent
torque lock, set the parking brake
and then shift into P (Park). To find
out how, see“Shifting Into Park”
listed previously. If torque lock does occur, your
vehicle may need to be pushed
uphill by another vehicle to relieve
the parking pawl pressure, so you
can shift out of P (Park).
If you are towing a trailer and
parking on a hill, see
Driving
Characteristics and Towing Tips on
page 9-58.
Shifting out of Park
This vehicle is equipped with an
electronic shift lock release system.
The shift lock release is
designed to:
.Prevent ignition key removal (if
equipped) unless the shift lever
is in P (Park) with the shift lever
button fully released.
.Prevent movement of the shift
lever out of P (Park), unless the
ignition is in ON/RUN and the
brake pedal is applied. The shift 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
Jump Starting on
page 10-66.
To shift out of P (Park):
1. Apply the brake pedal.
2. Place the ignition in ON/RUN.
3. Press the shift lever button.
4. Move the shift lever to the
desired position.
If still unable to shift out of P (Park):
1. Fully release the shift lever button.
2. Hold the brake pedal down and press the shift lever button
again.
3. Move the shift lever to the desired position.

Black plate (25,1)Chevrolet Impala Owner Manual (GMNA-Localizing-U.S./Canada-7576026) -
2015 - crc 2nd edition - 8/21/14
Driving and Operating 9-25
Running the Vehicle
While Parked
It is better not to park with the
engine running.
If the vehicle is left with the engine
running, follow the proper steps to
be sure the vehicle will not move.
SeeShifting Into Park on page 9-22
and Engine Exhaust on page 9-24.
If parking on a hill and pulling a
trailer, see Driving Characteristics
and Towing Tips on page 9-58.
Automatic
Transmission
P (Park): This position locks the
front wheels. It is the best position
to use when you start the engine
because the vehicle cannot move
easily.
{Warning
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. 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 9-22.
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 must fully apply the
brake pedal then press the shift
lever button before you can shift
from P (Park) while the ignition key

Black plate (29,1)Chevrolet Impala Owner Manual (GMNA-Localizing-U.S./Canada-7576026) -
2015 - crc 2nd edition - 8/21/14
Driving and Operating 9-29
Parking Brake
The Electric Parking Brake (EPB)
switch is on the left side of the
instrument panel. The EPB can
always be activated, even if the
ignition is off. To prevent draining
the battery, avoid repeated cycles of
the EPB when the engine is not
running.
The system has a red parking brake
status light and an amber parking
brake warning light. SeeElectric
Parking Brake Light on page 5-20
and Service Electric Parking Brake Light on page 5-20. There are also
parking brake-related Driver
Information Center (DIC) messages.
See
Brake System Messages on
page 5-28. In case of insufficient
electrical power, the EPB cannot be
applied or released.
Before leaving the vehicle, check
the red parking brake status light to
ensure that the parking brake is
applied.
EPB Apply
To apply the EPB:
1. Be sure the vehicle is at a complete stop.
2. Lift up the EPB switch momentarily.
The red parking brake status light
will flash and then stay on once the
EPB is fully applied. If the red
parking brake status light flashes
continuously, then the EPB is only
partially applied or there is a
problem with the EPB. A DIC
message will display. Release the
EPB and try to apply it again. If the light does not come on, or keeps
flashing, have the vehicle serviced.
Do not drive the vehicle if the red
parking brake status light is flashing.
See your dealer. See
Electric
Parking Brake Light on page 5-20.
If the amber parking brake warning
light is on, lift up on the EPB switch
and hold it up. Continue to hold the
switch until the red parking brake
status light remains on. If the amber
parking brake warning light remains
on, see your dealer.
If the EPB is applied while the
vehicle is moving, the vehicle will
decelerate as long as the switch is
held up. If the switch is held up until
the vehicle comes to a stop, the
EPB will remain applied.
The vehicle may automatically apply
the EPB in some situations when
the vehicle is not moving. This is
normal, and is done to periodically
check the correct operation of the
EPB system.

Black plate (30,1)Chevrolet Impala Owner Manual (GMNA-Localizing-U.S./Canada-7576026) -
2015 - crc 2nd edition - 8/21/14
9-30 Driving and Operating
If the EPB fails to apply, the rear
wheels should be blocked to
prevent vehicle movement.
EPB Release
To release the EPB:
1. Place the ignition in the ACC/ACCESSORY or ON/RUN
position.
2. Apply and hold the brake pedal.
3. Push down momentarily on the EPB switch.
The EPB is released when the red
parking brake status light is off.
If the amber parking brake warning
light is on, release the EPB by
pushing down on the EPB switch
and holding it down. Continue to
hold the switch until the red parking
brake status light is off. If either light
stays on after release is attempted,
see your dealer.
{Caution
Driving with the parking brake on
can overheat the brake system
and cause premature wear or
damage to brake system parts.
Make sure that the parking brake
is fully released and the brake
warning light is off before driving.
Automatic EPB Release
The EPB will automatically release if
the vehicle is running, placed into
gear, and an attempt is made to
drive away. Avoid rapid acceleration
when the EPB is applied, to
preserve parking brake lining life.
If parking on a hill, or if the vehicle
is pulling a trailer, see Driving
Characteristics and Towing Tips on
page 9-58.
Brake Assist
The Brake Assist feature is
designed to assist the driver in
stopping or decreasing vehicle speed in emergency driving
conditions. This feature uses the
stability system hydraulic brake
control module to supplement the
power brake system under
conditions where the driver has
quickly and forcefully applied the
brake pedal in an attempt to quickly
stop or slow down the vehicle. The
stability system hydraulic brake
control module increases brake
pressure at each corner of the
vehicle until the ABS activates.
Minor brake pedal pulsation or
pedal movement during this time is
normal and the driver should
continue to apply the brake pedal as
the driving situation dictates. The
Brake Assist feature will
automatically disengage when the
brake pedal is released or brake
pedal pressure is quickly
decreased.
Hill Start Assist (HSA)
Some vehicles have a Hill Start
Assist (HSA) feature, which may be
useful when the vehicle is stopped