2001 GMC YUKON XL DENALI heater

2-
2-1
Section 2 Features and Controls
Here you can learn about the many standard and optional features on your vehicle, and information on starting,
shifting and braking. Also explained are the instrument panel and the warning systems that tell you if everything is
working properly
-- and what to do if you have a problem.
2
-2 Windows
2
-4 Keys
2
-6 Door Locks
2
-8 Keyless Entry System
2
-12 Liftgate/Liftgate Glass
2
-12 Theft
2
-14 Content Theft-Deterrent
2
-15 Passlock

2-16 New Vehicle ªBreak Inº
2
-16 Ignition Positions
2
-17 Starting Your Engine
2
-19 Engine Coolant Heater (If Equipped)
2
-20 Automatic Transmission Operation
2
-23 Parking Brake
2
-24 Shifting Into PARK (P)
2
-27 Shifting Out of PARK (P)
2
-27 Parking Over Things That Burn
2
-28 Engine Exhaust2
-28 Running Your Engine While You're Parked
2
-30 Locking Rear Axle
2
-30 All-Wheel Drive
2
-30 Tilt Wheel
2
-31 Turn Signal/Multifunction Lever
2
-37 Exterior Lamps
2
-40 Interior Lamps
2
-42 Mirrors
2
-46 Storage Compartments
2
-53 OnStar
System (If Equipped)
2
-57 Sunroof (If Equipped)
2
-58 HomeLink
Transmitter
2
-62 The Instrument Panel - Your
Information System
2
-64 Instrument Panel Cluster
2
-65 Warning Lights, Gages and Indicators
2
-77 Message Center
2
-83 Secondary Information Center (SIC)

2-19
Engine Coolant Heater (If Equipped)
In very cold weather,
0
F (
-18
C) or
colder, the engine
coolant heater can
help. You'll get easier
starting and better fuel
economy during
engine warm
-up.
Usually, the coolant heater should be plugged in a
minimum of four hours prior to starting your vehicle.
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord. The
cord is located on the driver's side of the engine
compartment, near the power steering fluid reservoir.
3. Plug it into a normal, grounded 110
-volt AC outlet.
CAUTION:
Plugging the cord into an ungrounded outlet
could cause an electrical shock. Also, the wrong
kind of extension cord could overheat and cause
a fire. You could be seriously injured. Plug the
cord into a properly grounded three
-prong
11 0
-volt AC outlet. If the cord won't reach, use a
heavy
-duty three-prong extension cord rated for
at least 15 amps.
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 don't, it could
be damaged.
How long should you keep the coolant heater plugged
in? The answer depends on the outside temperature, the
kind of oil you have, and some other things. Instead of
trying to list everything here, we ask that you contact
your dealer in the area where you'll be parking your
vehicle. The dealer can give you the best advice for that
particular area.

2-22
DRIVE (D): This position is for normal driving. If you
need more power for passing, and you're:

Going less than about 35 mph (55 km/h), push your
accelerator pedal about halfway down.

Going about 35 mph (55 km/h) or more, push the
accelerator all the way down.
You'll shift down to the next gear and have more power.
DRIVE (D) can be used when towing a trailer, carrying
a heavy load, driving on steep hills or for off
-road
driving. You may want to shift the transmission to
THIRD (3) or, if necessary, a lower gear selection if the
transmission shifts too often.
THIRD (3): This position is also used for normal
driving, however it offers more power and lower fuel
economy than DRIVE (D).
SECOND (2): This position gives you more power but
lower fuel economy. You can use SECOND (2) on hills.
It can help control your speed as you go down steep
mountain roads, but then you would also want to use
your brakes off and on.
If you manually select SECOND (2), the transmission will
drive in second gear. You may use this feature for reducing
the speed of the rear wheels when you are trying to start
your vehicle from a stop on slippery road surfaces. Once
the vehicle is moving, shift into DRIVE (D).FIRST (1): This position gives you even more power
(but lower fuel economy) than SECOND (2). You can
use it on very steep hills, or in deep snow or mud. If the
shift lever is put in FIRST (1) while the vehicle is
moving forward, the transmission won't shift into first
gear until the vehicle is going slowly enough.
NOTICE:
If your rear wheels can't rotate, don't try to
drive. This might happen if you were stuck in
very deep sand or mud or were up against a solid
object. You could damage your transmission.
Also, if you stop when going uphill, don't hold
your vehicle there with only the accelerator
pedal. This could overheat and damage the
transmission. Use your brakes or shift into
PARK (P) to hold your vehicle in position on
a hill.
On cold days, approximately 32F (0C) or colder, your
transmission is designed to shift differently until the
engine reaches normal operating temperature. This is
intended to improve heater performance.

3-3
Mode Knob - Automatic Operation
The right knob on the control panel allows you to
choose the direction of air delivery. When the system
is set in AUTO mode, sensors will control the air
delivery mode. Air will come primarily from the floor
or instrument panel outlets, with some air directed to
the windshield to prevent fogging.
When the system is in AUTO mode, the air conditioning
light will turn on, and the recirculation and outside air
lights turn off. With the system in full auto control
(both the fan and mode knobs in AUTO), you still
have the ability to override any function. However,
continually overriding the outside air or the A/C
compressor will limit the ability of the system to
cool the vehicle quickly.
If you push a button for a function which is not
available, the light next to that button will flash
three times to alert you that it's not available.
To find your comfort zone, start with the 74
F (23
C)
setting and allow about 20 minutes for the system to
adjust the temperature if necessary.With the automatic setting, the air conditioning
compressor automatically cycles when needed to cool
the air. In cold weather, when the system senses the need
for heat, the airflow will be directed out of the floor
outlets. As the interior temperature approaches a desired
setting, the fan speed will decrease. To maintain interior
comfort, the airflow will adjust between the instrument
panel air outlets and floor outlets. On bright sunny days
in cool weather, the airflow may come out of the air
conditioning and floor outlets (bi
-level mode) to
maintain comfort and prevent stuffiness.
To avoid blowing cold air in cold weather, the system
will delay turning on the fan until warm air is available.
The length of delay depends on the outside air
temperature, engine coolant temperature or the time
since the engine was last started. As the coolant warms
up, the fan speed will gradually increase and air will
flow from the heater outlets, with some airflow to
the windshield to prevent fogging under most
normal conditions.
Be careful not to put anything over the solar sensor
located around the center of the instrument panel.
This sensor is used by the automatic system to
regulate temperature.

3-4
Mode Knob - Manual Operation
The right knob on the control panel allows you to
choose the direction of air delivery.
You can choose to set the climate control system
operations yourself, or let the system work for you
by placing the system in AUTO mode. See ªMode
Knob
- Automatic Operationº earlier in this section.
VENT: This setting directs most of the air through
the instrument panel outlets and a small amount through
the floor outlets.
BI-LEVEL: This setting delivers air through the
floor outlets as well as the instrument panel outlets.
HEATER: This setting directs most of the
warmed air through the floor outlets and some air
through the windshield defroster outlets.
BLEND: This setting divides airflow equally
between the heater floor outlet and the windshield
defroster outlets. The air conditioning compressor may
run to dehumidify the air to prevent window fogging.
DEFROST: This setting directs most air through
the windshield defroster outlets and some through the
outlets. The air conditioning compressor may run to
dehumidify the air to prevent window fogging.
OUTSIDE AIR: This setting should be used
for normal system operation and directs the system
to use outside air. Using outside air will limit stale air
odors and help to prevent excessively humid interior air
(from wet boots or clothing or maximum passenger
loads) from being redirected onto windows.
Pressing the outside air button will cancel the
recirculation button.
RECIRCULATION: This setting limits the
amount of outside air entering the vehicle to a very small
amount. This will be helpful to limit odors entering the
vehicle and will assist in reaching comfort in very hot
temperature conditions. Pressing recirculation will cause
the system to recirculate interior air continuously and
may cause the vehicle windows to fog if the passenger
compartment floor is excessively wet.

3-5
Pressing the recirculation button will cancel outside
air operation. To return to normal system operation and
to prevent stale passenger compartment air, be sure to
return to the outside air position.
Recirculation will not be available in heater, blend or
defrost modes to help reduce window fogging. If the
recirculation button is pressed in theses modes, the
indicator light for recirculation will flash three times
indicating that forced outside air is activated and
recirculation is not available.
If the air conditioning system is activated and system
demand is high in situations such as city traffic, idling,
or very hot weather, the system will automatically
switch from outside air to recirculation. The indicator
light will not change. After demand on the system is
not so great, the system will return back to outside air. A/C: Press this button to turn the air
conditioning on and off. The system will cool and
dehumidify the air inside the vehicle when the A/C light
is on. When in AUTO, the A/C is automatically engaged
when necessary.
Air conditioning will be automatically disabled when
the outside temperature drops below a level at which air
conditioning is ineffective.
Rear Air Conditioning and Heating Systems
Your vehicle is equipped with a rear heating and air
conditioning system that can increase and decrease
airflow and temperature based on passenger needs.
Vehicles equipped with a sunroof will have the manual
control heating and air conditioning system. Vehicles
without a sunroof will be equipped with the Electronic
Climate Control System

3-6 Rear Air Conditioning and Rear Heater
(With Sunroof)
Your vehicle has the rear air conditioning and rear heater
system combination. Controls are provided to regulate
temperature, location and speed of the airflow.
Front ControlTo adjust the airflow speed, turn the fan knob located on
the left side to the desired setting.
To regulate the airflow location, adjust the right knob on
the control panel. Turn the knob clockwise for floor vent
airflow or counterclockwise for headliner vent airflow.
Generally, the upper vents are used for air conditioning
and the floor vents for heating. The knob can be set to
any blend setting.
To adjust the air temperature, turn the temperature knob
on the center of the control panel.
For warmer air, turn the knob clockwise toward red. For
cooler air, turn the knob counterclockwise toward blue.

3-8 Air Conditioning
On hot days, open the windows long enough to let hot
air inside escape. This reduces the time it takes for your
vehicle to cool down. Then keep your windows closed
for the air conditioner to work its best.
The A/C button, below the mode knob, allows the
air coming into your vehicle to be cooled. This setting
is useful for normal cooling on hot days. When you
use A/C with the recirculation button pushed in,
turn off recirculation as soon as the vehicle reaches a
comfortable interior temperature.
Using A/C with the recirculation setting active
allows the air inside your vehicle to be recirculated.
This setting helps to maximize your air conditioner's
performance and your vehicle's fuel economy.
This setting also cools air the fastest and can be used
to keep unwanted odors and/or dust from entering the
vehicle. When using the air conditioner, turn off the
recirculation setting and use the outside air setting after
the vehicle reaches a comfortable interior temperature.
When the right knob on the control panel is between
heater and defrost, the recirculation feature will not
function to reduce window fogging.Passenger Compartment Air Filter
Your vehicle is equipped with a passenger compartment
air filter, which filters outside air entering the vehicle.
For information on replacing the filter see ªPassenger
Compartment Air Filterº in the Index.
Heating
The heater works best if you keep your windows closed
while using it. On cold days, use the heater or vent/heat
setting with the temperature knob in the red area.
On cold days, approximately 32
F (
-0
C) or
lower, you may experience differences in how
the transmission shifts until the engine is warm.
This feature automatically reduces the time it takes for
the engine to reach normal operating temperature and
shortens the time it takes the heater to reach full output.
If you use the engine coolant heater before starting
your engine in cold weather, 20
F (
-8
C) or lower,
the heating system will produce warmer air faster to heat
the passenger compartment.
The use of an engine coolant heater also reduces the
time it takes for the engine to reach normal operating
temperature. For more information, see ªEngine Coolant
Heaterº in the Index.