GMC Terrain 2018 Owner's Manual page 184

If the vehicle must be turned off in
an emergency:
1. Brake using a firm and steady
pressure. Do not pump the
brakes repeatedly. This may
deplete power assist, requiring
increased brake pedal force.
2. Shift the vehicle to N (Neutral).
This can be done while the
vehicle is moving. After shifting
to N (Neutral), firmly apply the
brakes and steer the vehicle to
a safe location.
3. Come to a complete stop, shift
to P (Park), and turn the
ignition off. The vehicle must
be in P (Park) to turn the
ignition off.
4. Set the electric parking brake.
See Electric Parking Brake
0 206.
Warning
Turning off the vehicle while
moving may cause loss of power
assist in the brake and steering
(Continued)
Warning (Continued)
systems and disable the airbags.
While driving, only shut the
vehicle off in an emergency.
If the vehicle cannot be pulled over
and must be shut off while driving,
press and hold ENGINE START/
STOP for longer than two seconds,
or press twice in five seconds.
ACC/ACCESSORY (Amber
Indicator Light) : This mode allows
you to use some electrical
accessories when the engine is off.
With the ignition off, pressing the
button one time without the brake
pedal applied will place the ignition
system in ACC/ACCESSORY.
The ignition will switch from ACC/
ACCESSORY to OFF after
five minutes to prevent battery
rundown.
ON/RUN/START (Green Indicator
Light) : This mode is for starting
and driving. With the ignition off and
the brake pedal applied, pressing
the button once will turn the ignition
Driving and Operating
on. Once engine cranking begins,
release the button. Engine cranking
will continue until the engine starts.
See Starting the Engine 0 184. The
ignition will then remain in on.
Service Mode
This power mode is available for
service and diagnostics, and to
verify the proper operation of the
malfunction indicator lamp as may
be required for emission inspection
purposes. With the vehicle off and
the brake pedal not applied,
pressing and holding ENGINE
START/STOP for more than
five seconds will place the vehicle in
Service Mode. The instruments and
audio systems will operate as they
do in ON/RUN, but the vehicle will
not be able to be driven. The engine
will not start in Service Mode. Press
ENGINE START/STOP again to turn
the vehicle off.
183