power steering GMC YUKON DENALI 2003 Owners Manual

Engine Coolant Heater
Your vehicle may be equipped with an engine
coolant heater.
I
Usually, the coolant heater sho 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.
luld be ph Jgged in a
minimum of four hours prior to starting your vehicle.
At temperatures above 32°F (OOC), use of the coolant
heater is not required.
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 1 IO-volt AC outlet.
PIL,ging the cord inl, an ,..grc,.lded out.,_
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.
2-21

The main components of your instrument panel
are the following:
A. Air Outlets
€3. Exterior Lamps Contro!
C. Turn SignaVMultifunction Lever
D. Onstar@ and Radio Steering Wheel Buttons
E. Instrument Panel Cluster
F. Shift Lever/Tow/Haul Selector Button
G. Audio System
H. Dome Override Button
I. Rear Wiper Washer
J. Fog Lamps Button
K. Driver Information Center (DIC) Buttons
L. Parking Brake Release
M. Tilt Lever
N. Comfort Control System
0. Storage Area
P. Compact Disc Changer
Q. Accessory Power Outlet
R. StabiliTrak@ Button
S. Glove Box
Hazard Warning Flashers
Your hazard warning flashers let you warn others. They
also let police know you have a problem, Your front
and rear turn signal
lamps will flash on and off.
But they won’t flash if you’re braking.
3-5

Driver Information Center (DIC)
The DIC display is located on the instrument panel
cluster above the steering wheel. The DIC can display
information such as the trip odometer, fuel economy and
personalization features.
A (Trip Information): This button will display the
odometer, personal trip odometer, business trip
odometer, hourmeter, annual log and the timer.
B (Fuel Information): This button will display the
current range, average fuel economy, instant fuel
economy and engine oil life.
C (Personalization): This button will change personal
options available on your vehicle.
D (Select): This button resets certain functions and
turns off
or acknowledges nessages on the DIC.
DIC Operation and Displays
The DIC comes on when the ignition is on. After a short
delay the DIC will display the current driver
(1 or 2)
and the information that was last displayed before the
engine was turned off.
If a problem is detected, a warning message will appear
on the display. Pressing any of the four buttons will
acknowledge (clear) most current warnings or service
messages. Some warnings that cannot be
acknowledged (cleared) are: ENGINE OVERHEATED,
OIL PRESSURE LOW, REDUCED ENGINE POWER,
TRANS HOT IDLE ENGINE. These warnings must
be dealt with immediately and therefore cannot
be cleared until the problem has been corrected.
The DIC has different modes which can be accessed
by
pressing the four buttons on the DIC. These buttons
are trip information, fuel information, personalization and
select. The button functions are detailed in the
following.
3-43

The traction control system may activate on dry or
rough roads or under conditions such as heavy
acceleration while turning or abrupt upshifts/downshifts
of the transmission. When this happens you may
notice a reduction in acceleration, or may hear
a noise
or vibration. This is normal.
If your vehicle is in cruise control when the system
activates, the STABILITY SYS ACTIVE message will
appear on the Driver Information Center and the cruise
control will automatically disengage. When road
conditions allow you
to use cruise again, you may
re-engage the cruise control. See “Cruise Control” under
Turn SignaVMultifunction
Lever on page 3-7
Stabilitrak@may also turn off automatically if it
determines that a problem exists with the system. If the
problem does not clear itself after restarting the
vehicle, you should see your dealer for service.
Power Steering
If you lose power steering assist because the engine
stops or the system is not functioning, you can steer but
it will take much more effort.
Steering Tips
Driving on Curves
It’s important to take curves at a reasonable speed.
A
lot of the “driver lost control” accidents mentioned on
the news happen on curves. Here’s why:
Experienced driver or beginner, each of us is subject to
the same laws of physics when driving on curves.
The traction of the tires against the road surface makes
it possible for the vehicle
to change its path when
you turn the front wheels. If there’s no traction, inertia
will keep the vehicle going in the same direction.
If
you’ve ever tried to steer a vehicle on wet ice, you’ll
understand this.
The traction you can get
in a curve depends on the
condition of your tires and the road surface, the angle at
which the curve is banked, and your speed. While you’re
in a curve, speed is the one factor you can control.
Suppose you’re steering through a sharp curve. Then you
suddenly accelerate. Both control systems
- steering
and acceleration
- have to do their work where the tires
meet the road. Adding the sudden acceleration can
demand too much of those places. You can lose control.
What should you do
if this ever happens? Ease up on
the accelerator pedal, steer the vehicle the way
you want
it to go, and slow down.
4-1 1

Driving Uphill
Once you decide you can safely drive up the hill, you
need to take some special steps.
Use a low year and get a firm grip on the
steering wheel.
your speed. Don’t use more power than you
need, because you don’t want your wheels to start
spinning or sliding.
Try to drive straight up the hill if at all possible. If
the path twists and turns, you might want to find
another route.
Get a smooth start up the hill and try to maintain
0 Sound the horn as you approach the top of the hill
to let opposing traffic know you’re there.
Use your headlamps even during the day. They
make
you more visible to oncoming traffic.
Turning or driving across steep hills can be
dangerous. You could lose traction, slide
sideways, and possibly roll over. You could be
seriously injured or killed. When driving up
hills, always try to go straight up.
Ease up on your speed as you approach the top of
the hill.
Attach a flag to the vehicle to make you more
visible to approaching traffic on trails or hills. Driving to the top (crest)
of a hill
a, ,ull speed
can cause an accident. There could be a
drop-off, embankment, cliff, or even another
vehicle. You could be seriously injured or killed.
As you near the top of a hill, slow down
and stay alert.
Q: What should I do if my vehicle stalls, or is
about to stall, and
I can’t make it up the hill?
A: If this happens, there are some things you should
do and there are some things you must not do. First, here’s what you
should do:
Push the brake pedal to stop the vehicle and keep
it from rolling backwards.
Also, apply the parking
brake.
4-2 1

Section 5 Service and Appearance Care
Service ............................................................ 5.3
Doing Your Own Service Work
......................... 5-3
Adding Equipment
to the Outside of Your
Vehicle
.................................................. 5-4
................................................................ Fuel 5.5
Gasoline Octane ............................................ 5.5
Gasoline Specifications ................................... 5-5
California Fuel ............................................... 5-6
Additives
....................................................... 5.6
Fuels in Foreign Countries
............................... 5-6
Filling Your Tank
............................................ 5-7
Filling a Portable Fuel Container ....................... 5.9
the Hood .................... , .................... 5.10
Hood Release ...................... ................ 5-10
Engine Compartment Overview ....... ......... 5-12
Engine Oil ....................................... ..... 5.13
Engine Air Cleaner/Filter ............................. 5.17
Automatic Transmission Fluid ......................... 5-20
Engine Coolant ......................................... 5-22
Checking Things Under
~~
Coolant Surge Tank Pressure Cap ............... 5-25
Engine Overheating ....................................... 5-25
Cooling System ............................................ 5.28
Engine Fan Noise ......................................... 5.33
Power Steering Fluid
..................................... 5-34
Windshield Washer Fluid
................................ 5.34
Brakes
........................................................ 5.36
Battery
........................................................ 5-39
Jump Starting
............................................... 5.40
All-Wheel Drive .............................................. 5.46
Rear Axle .................................. .......... 5-48
Bulb Replacement .......................................... 5-49
Halogen Bulbs .............................................. 5-49
Headlamps
.................................................. 5-49
Running Lamps
......................................... 5-50
Center High-Mounted Stoplamp (CHMSL) ......... 5-52
Taillamps ..................................................... 5-52
Replacement Bulbs ................................... 5.53
Front Turn Signal, Sidemarker and Daytime
5- 1

A. Engine Air CleanedFilter
B. Coolant Surge Tank
C. Air Filter Restriction Indicator
D. Engine Qii Dipstick
E. Engine Oil Fill
F. Automatic Transmission Dipstick
G. Fan
H. Remote Negative (-) Terminal (GND)
I. Remote Positive (+) Terminal
J. Power Steering Fluid Reservoir (Out of View)
K. Brake Master Cylinder Reservoir
L. Underhood Fuse Block
M. Battery
N. Windshield Washer Fluid Reservoir
Before closing the hood, be sure all filler caps are on
properly. Pull down the hood and close
it firmly.
Engine Oil
If the CHECK OIL LEVEL message appears on the
instrument cluster, it means you need to check
your engine oil level right away.
For more information, see “CHECK OIL LEVEL” under
DIC Warnings and Messages on page 3-52.
You should check your engine oil level regularly; this is
an added reminder.
Checking Engine Oil
It’s a good idea to check your engine oil every time you
get fuel. In order to get an accurate reading, the oil
must be warm and the vehicle must be on level ground.
The engine oil dipstick has a yellow loop handle and
is located in the engine
compartment on the
passenger’s side of the
vehicle. See Engine
Compartment Overview on
page
5- 12 for more
information on location.
Turn
off the engine and give the oil several minutes to
drain back into the oil pan. If you don’t, the oil
dipstick might not show the actual level.
Pull out the dipstick and clean it with a paper towel or
cloth, then push it back in all the way. Remove it again,
keeping the tip down, and check the level.
5-1 3

Power Steering Fluid
-
When to Check Power Steering Fluid
It is not necessary to regularly check power steering fluid
unless you suspect there is a leak in the system or
you hear an unusual noise. A fluid
loss in this system
could indicate a problem. Have the system inspected
and repaired. See Engine Compartment Overview
on page
5-72 for reservoir location.
How to Check Power Steering Fluid
Turn the key off, let the engine compartment cool down.
wipe the cap and the top of the reservoir clean, then
unscrew the cap and wipe the dipstick with a clean rag.
Replace the cap and completely tighten it. Then
remove the cap again and look at the fluid level on the
dipstick.
The level should be at the
FULL COLD mark. If
necessary, add only enough fluid to bring the level up to
the mark.
What to Use
To determine what kind of fluid to use, see Part D:
Recommended Fluids and Lubricants on page 6-15.
Always use the proper fluid. Failure to use the proper
fluid can cause leaks and damage hoses and seals.
Windshield Washer Fluid
What to Use
When you need windshield washer fluid, be sure to read
the manufacturer's instructions before use. If you will
be operating your vehicle in an area where the
temperature may fall below freezing, use a fluid that has
sufficient protection against freezing. See Engine
Compartment Overview on page
5-72 for reservoir
location.
5-34

Center Instrument Panel Fuse Block
The center instrument panel utility block is located
underneath the instrument panel,
to the left of the
steering column.
A FRT
[ 12-WAY) BODY (A) WHT (B)
HDLNR 1 (A)
12-WAY
1 2-WAY
5-90
SL RIDE
HDLR
2 Headliner Wiring Connector
Ride Control
Harness
Connection ~~ [BODY I Body Wiring Connector ---- - I Utl-uti Rear Defogger Relay
HDLNR
1 Headliner Wiring Connector 1
SPARE RELAY Not Used
CB
SEAT
CB RT DOOR Driver
and Passenger Seat
Module Circuit Breaker
Right Power Window Circuit
Breaker
SPARE Not Used
INFO Infotainment Harness
Connection

Part C: Periodic Maintenance
Inspections
Listed in this part are inspections and services which
should be performed at least twice a year (for instance,
each spring and fall).
You should let your dealer’s
service department or other qualified service center do
these jobs. Make sure any necessary repairs are
completed at once.
Proper procedures
to perform these services may be
found in a service manual. See Service Publications
Ordering Information on page
7- IO.
Steering and Suspension Inspection
Inspect the front and rear suspension and steering
system for damaged, loose or missing parts, signs of
wear or lack of lubrication. Inspect the power steering
lines and hoses for proper hook-up, binding, leaks,
cracks, chafing, etc.
Exhaust System Inspection
Inspect the complete exhaust system. Inspect the body
near the exhaust system. Look for broken, damaged,
missing or out-of-position parts as well as open seams,
holes, loose connections or other conditions which
could cause a heat build-up in the floor pan or could let
exhaust fumes into the vehicle. See Engine Exhaust
on page 2-29.
Fuel System Inspection
Engine Cooling System Inspection
Inspect the complete fuel system for damage or leaks.
Inspect the hoses and have them replaced
if they
are cracked, swollen or deteriorated. Inspect all pipes,
fittings and clamps; replace as needed. Clean the
outside of the radiator and air conditioning condenser.
To help ensure proper operation, a pressure test of
the cooling system and pressure cap is recommended
at least once a year.
Transfer Case and Front Axle
(All-Wheel Drive) Inspection
Every 12 months, or at engine oil change intervals,
check front axle and transfer case and add lubricant
when necessary.
A fluid loss could indicate a problem.
Check and have it repaired,
if needed. Check vent
hose at transfer case for kinks and proper installation.
Brake System Inspection
Inspect the complete system. Inspect brake lines and
hoses for proper hook-up, binding, leaks, cracks,
chafing, etc. Inspect disc brake pads for wear and rotors
for surface condition. Inspect other brake parts,
including calipers, parking brake, etc. You may need
to
have your brakes inspected more often if your driving
habits or conditions result in frequent braking.
6-1 4