2009 GMC YUKON HYBRID hood open

Auto Stop
The vehicle has an Auto Stop feature. After a successful
engine start, the engine may turn off and operate in the
Auto Stop mode. Some of the vehicle conditions that
allow the engine to stop running and enter the Auto Stop
mode are:
•Ignition switch is in the ON/RUN position.
•The hood is closed.
•The gear selector is in P (Park), N (Neutral) or
D (Drive).
•The hybrid battery is at an acceptable state of
charge.
•The hybrid battery voltage, temperature or power
limits are not exceeded. In very hot conditions,
Auto Stop may be unavailable until the hybrid battery
has cooled.
•The engine is at operating temperature.
If you are on an incline, the hybrid drive motor can help
keep the vehicle from rolling backwards, even if the
engine is in Auto Stop.With your foot off the brake and the vehicle on level
ground, the hybrid drive motor may cause the vehicle
to roll slowly forward, even when the engine is in
Auto Stop.
Keep your foot firmly on the brake pedal until you are
ready for the vehicle to move.
Engine OFF and AUTO STOP modes are indicated on
the tachometer display. When the tachometer needle
indicates OFF, the engine is not running and will remain
off until the ignition key is placed in the START position
or a remote vehicle start is performed. When the
tachometer needle indicates AUTO STOP, the hybrid
system is on, the engine is not running, but may
Auto Start at any time without notice. SeeTachometer
on page 3-4for more information.
A chime will sound if the driver door is opened while
in Auto Stop as a reminder that the ignition switch is
not in the LOCK/OFF position. Always turn the ignition
switch to LOCK/OFF and remove the key from the
ignition switch when exiting the vehicle.
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Auto Start
The vehicle also has an Auto Start feature. The engine
will remain off while in Auto Stop mode until vehicle
conditions require the engine to run. The near-instant
starting of the engine from Auto Stop mode is called
Auto Start. Some of the vehicle conditions that
may cause the engine to Auto Start are:
•The hood is opened.
•The gear selector is in M (Manual Mode) or
R (Reverse).
•The hybrid battery state of charge is too low.
•The hybrid battery voltage, temperature or power
limits are exceeded.
•The engine is not at operating temperature.
•Acceleration demands require the use of the engine.
EV Mode
The vehicle also has an EV mode which uses only the
electric motor to move the vehicle. Depending on
the state of battery charge, the vehicle can travel up to
two miles (3.2 km) in EV mode. EV mode is unavailable
when the vehicle is out of fuel.
With light acceleration, the vehicle will drive in EV mode.
If increased acceleration is required, or the vehicle
reaches approximately 25 mph (40 km/h), the engine
will start automatically. The engine shuts off at speeds
below 25 mph (40 km/h) unless the transmission is
in M (Manual Mode) or Auto Stop is disabled.
During heavy acceleration, both the engine and hybrid
electric motors supply power. A sensation similar to
a transmission gear change can be felt as the
transmission changes modes. Engine RPM may remain
above 4,000 RPM for a longer period during hard
acceleration.
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SERVICE BATTERY CHARGING
SYSTEM
If the hybrid battery system faults or fails this message
will appear on the DIC. The engine auto stop feature
will be disabled and the battery/charging system light will
appear in the instrument panel cluster. See “Battery
Warning Light” in the owner manual Index.
Driving with this light on could drain your batteries.
Have the electrical system checked as soon as possible.
Pressing the select button or the trip odometer reset
stem on the instrument panel cluster will acknowledge
this message and clear it from the DIC display.
HOOD OPEN
If the hood is not fully closed or there is a problem
with the hood switch, this message will be displayed.
Close the hood to clear the message. If the HOOD
OPEN message continues to be displayed after
verifying the hood is closed, you should have the hood
switch serviced. Pressing the select button or the
trip odometer reset stem on the instrument panel cluster
will acknowledge this message and clear it from the
DIC display.
When this message is displayed, the auto stop
function will not operate. If the vehicle is in auto stop
mode when this message appears, the engine will
instantly start.
OIL PRESSURE LOW STOP ENGINE
If engine oil pressure is low, this message will be
displayed on the DIC. Stop the vehicle as soon as safely
possible and do not operate it until the cause of the
low oil pressure has been corrected. Check your oil level
as soon as possible and have your vehicle serviced.
See “Engine Oil” in the owner manual Index.
SERVICE BRAKE SYSTEM
This message will be displayed if there is a problem
with the brake system. You will still be able to brake, but
it will be noticeably more difficult. Pull off the road to a
safe location and have your vehicle towed to the nearest
dealer/retailer for service. See “Brakes,” “Brake System
Warning Light,” and “ABS Brake System Warning
Light” in the owner manual Index.
SERVICE HYBRID SYSTEM
If this message is displayed on the DIC, the vehicle may
continue to operate, but you need to have it serviced
as soon as possible.
SERVICE POWER STEERING
This message displays if a problem has been detected
with the electric power steering. Have your vehicle
serviced by your dealer/retailer immediately.
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If doing some of your own service work, use the proper
service manual. It tells you much more about how to
service the vehicle than this manual can. To order
the proper service manual, see “Service Publications
Ordering Information” in the owner manual.
This vehicle has an airbag system. Before attempting
to do your own service work, see “Servicing Your
Airbag-Equipped Vehicle” in the owner manual.
Keep a record with all parts receipts and list the
mileage and the date of any service work performed.
See “Maintenance Record” in the owner manual.Checking Things Under
the Hood
High Voltage Devices and Wiring
{CAUTION:
Exposure to high voltage can cause shock, burns,
and even death. The high voltage systems in your
vehicle can only be serviced by technicians with
special training.
High voltage devices are identified by labels.
Do not remove, open, take apart, or modify these
devices. High voltage cable or wiring has orange
covering. Do not probe, tamper with, cut, or modify
high voltage cable or wiring.
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Engine Compartment Overview
When you open the hood on your vehicle, you will see:
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Notice:If you leave the radio or other accessories
on during the jump starting procedure, they
could be damaged. The repairs would not be
covered by the warranty. Always turn off the radio
and other accessories when jump starting the
vehicle.
3. Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter or the accessory power outlets. Turn off
the radio and all the lamps that are not needed.
This avoids sparks and helps save both batteries.
It could save the radio!
4. Open the hood on the other vehicle and locate the
positive (+) and negative (−) terminal locations on
that vehicle.
Your vehicle has a remote positive (+) and a remote
negative (−) jump starting terminal. You should
always use these remote terminals instead of the
terminals on the battery.If the vehicle has a remote positive (+), it is located
under a red plastic cover at the positive battery
post. To uncover the remote positive (+) terminal,
open the red plastic cover.
5. The remote negative (−) is a solid engine ground.
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