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GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S/Canada-
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212 Driving and Operating
be required for emission inspection
purposes. With the vehicle off, and
the brake pedal not applied,
pressing and holding the button for
more than five seconds will place
the vehicle in Service Only 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 Only Mode. Press the
button again to turn the vehicle off.
Ignition Positions (Key
Access)
Vehicles with Key Access have an
ignition switch with four different
positions.
To shift out of P (Park), the ignition
must be in ON/RUN or ACC/
ACCESSORY and the regular brake
pedal must be applied.
0 (STOPPING THE ENGINE/LOCK/
OFF) :When the vehicle is stopped,
turn the ignition switch to LOCK/
OFF to turn the engine off. Retained
Accessory Power (RAP) will remain
active. See Retained Accessory
Power (RAP) 0216.
This position locks the ignition and
steering wheel. It also locks the
transmission on automatic
transmission vehicles. The key can
be removed in LOCK/OFF.
The steering can bind with the
wheels turned off center. If this
happens, move the steering wheel
from right to left while turning the
key to ACC/ACCESSORY. If this
does not work, then the vehicle
needs service. Do not turn the engine off when the
vehicle is moving. This will cause a
loss of power assist in the brake
and steering systems and disable
the airbags.
If the vehicle must be shut 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 to LOCK/OFF. On
vehicles with an automatic
transmission, the shift lever
must be in P (Park) to turn the
ignition switch to the LOCK/
OFF position.
4. Set the parking brake. See Parking Brake 0231.
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GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S/Canada-
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216 Driving and Operating
Warning (Continued)
function. An ungrounded
outlet could cause an
electric shock.
. Use a weatherproof,
heavy-duty, 15 amp-rated
extension cord if needed.
Failure to use the
recommended extension
cord in good operating
condition, or using a
damaged heater or
extension cord, could make
it overheat and cause a fire,
property damage, electric
shock, and injury.
. Do not operate the vehicle
with the heater cord
permanently attached to the
(Continued)
Warning (Continued)
vehicle. Possible heater
cord and thermostat
damage could occur.
. While in use, do not let the
heater cord touch vehicle
parts or sharp edges. Never
close the hood on the
heater cord.
. Before starting the vehicle,
unplug the cord, reattach
the cover to the plug, and
securely fasten the cord.
Keep the cord away from
any moving parts.
4. Before starting the engine, be sure to unplug and store the
cord as it was before to keep it
away from moving engine
parts. If you do not, it could be
damaged.
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)
The following vehicle accessories
can be used for up to 10 minutes
after the engine is turned off:
. Audio System
. Power Windows
. OnStar System (if equipped)
. Sunroof (if equipped)
. Accessory Power Outlets. The
console and center seat outlets
are RAP powered.
These features work when the key
is in ON/RUN or ACC/
ACCESSORY. Once the key is
turned from ON/RUN to LOCK/OFF,
the windows and sunroof continue
to work up to 10 minutes until any
door is opened. The radio continues
to work for up to 10 minutes or until
the driver door is opened.
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GMC Yukon/Yukon XL Owner Manual (GMNA-Localizing-U.S/Canada-
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398 OnStar
Calling 911 Emergency
1. Press=. System responds:
“OnStar ready.”
2. Say “Call.”System responds:
“Call. Please say the name or
number to call.”
3. Say “911”without pausing.
System responds: “911.”
4. Say “Call.”System responds:
“OK, dialing 911.”
Retrieve My Number
1. Press=. System responds:
“OnStar ready.”
2. Say “My number.” System
responds: “Your OnStar
Hands-Free Calling number is,”
then says the number.
End a Call
Press=. System responds: “Call
ended.”
Verify Minutes and Expiration
Press=and say “Minutes” then
“Verify” to check how many minutes
remain and their expiration date.
Diagnostics
Advanced Diagnostics provides a
status of the vehicle’ s key systems
with a monthly e-mail, or by
pressing
Q. Real-time Diagnostic
Alerts can be sent by e-mail or text.
The Proactive Alerts feature (if
available) can help predict and alert
of potential upcoming maintenance
issues with select components on
the vehicle, before they become a
problem.
OnStar can also monitor and report
tire pressure, if the vehicle is
equipped with a Tire Pressure
Monitoring System.
OnStar Additional
Information
In-Vehicle Audio Messages
Audio messages may play important
information at the following times:
. Prior to vehicle purchase.
Press
Qto set up an account.
. With the OnStar Basic Plan,
every 60 days.
. After change in ownership and
at 90 days.
Transferring Service
PressQto request account transfer
eligibility information. The Advisor
can cancel or change account
information.
Selling/Transferring the
Vehicle
Call 1-888-4ONSTAR
(1-888-466-7827) immediately to
terminate your OnStar services if
the vehicle is disposed of, sold,
transferred, or if the lease ends.