turn signal GMC YUKON 2003 Owner's Guide

Driving in Rain and on Wet Roads
Rain and wet roads can mean driving trouble. On a wet
road, you can’t stop, accelerate or turn as well
because your tire-to-road traction isn’t as good as on
dry roads. And, if your tires don’t have much tread left,
you’ll get even less traction. It’s always wise to go
slower and be cautious if rain starts to fall while you are
driving. The surface may get wet suddenly when your
reexes are tuned for driving on dry pavement.The heavier the rain, the harder it is to see. Even if your
windshield wiper blades are in good shape, a heavy
rain can make it harder to see road signs and
traffic signals, pavement markings, the edge of the road
and even people walking.
It’s wise to keep your wiping equipment in good shape
and keep your windshield washer tanklled with
washeruid. Replace your windshield wiper inserts
when they show signs of streaking or missing areas on
the windshield, or when strips of rubber start to
separate from the inserts.
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City Driving
One of the biggest problems with city streets is the
amount of traffic on them. You’ll want to watch out for
what the other drivers are doing and pay attention
to traffic signals.Here are ways to increase your safety in city driving:
Know the best way to get to where you are
going. Get a city map and plan your trip into
an unknown part of the city just as you would for a
cross-country trip.
Try to use the freeways that rim and crisscross
most large cities. You’ll save time and energy.
SeeFreeway Driving on page 4-43.
Treat a green light as a warning signal. A traffic
light is there because the corner is busy enough
to need it. When a light turns green, and just before
you start to move, check both ways for vehicles
that have not cleared the intersection or may
be running the red light.
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Freeway Driving
Mile for mile, freeways (also called thruways, parkways,
expressways, turnpikes or superhighways) are the
safest of all roads. But they have their own special rules.
The most important advice on freeway driving is:
Keep up with traffic and keep to the right. Drive at the
same speed most of the other drivers are driving.
Too-fast or too-slow driving breaks a smooth trafficow.
Treat the left lane on a freeway as a passing lane.At the entrance, there is usually a ramp that leads to the
freeway. If you have a clear view of the freeway as you
drive along the entrance ramp, you should begin to check
traffic. Try to determine where you expect to blend with
theow. Try to merge into the gap at close to the
prevailing speed. Switch on your turn signal, check your
mirrors and glance over your shoulder as often as
necessary. Try to blend smoothly with the trafficow.
Once you are on the freeway, adjust your speed to the
posted limit or to the prevailing rate if it’s slower.
Stay in the right lane unless you want to pass.
Before changing lanes, check your mirrors. Then use
your turn signal.
Just before you leave the lane, glance quickly over your
shoulder to make sure there isn’t another vehicle in
your“blind”spot.
Once you are moving on the freeway, make certain you
allow a reasonable following distance. Expect to
move slightly slower at night.
When you want to leave the freeway, move to the
proper lane well in advance. If you miss your exit, do
not, under any circumstances, stop and back up. Drive
on to the next exit.
The exit ramp can be curved, sometimes quite sharply.
The exit speed is usually posted.
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Automatic Level Control
The automatic level control rear suspension is available
on C/K 1500 vehicles and comes as a part of the
Autoride™suspension.
This type of level control is fully automatic and will provide
a better leveled riding position as well as better handling
under a variety of passenger and loading conditions. An
air compressor connected to the rear shocks will raise or
lower the rear of the vehicle to maintain proper vehicle
height. The system is activated when the ignition key is
turned to RUN and will automatically adjust vehicle height
thereafter. The system may exhaust (lower vehicle
height) for up to ten minutes after the ignition key has
been turned off. You may hear the air compressor
operating when the height is being adjusted.
If a self-equalizing hitch is being used, it is
recommended to allow the shocks to inate, thereby
leveling the vehicle prior to adjusting the hitch.
Autoride™
The Autoride™feature will provide a superior vehicle ride
and handling under a variety of passenger and loading
conditions.The system is fully automatic and uses a computer
controller to continuously monitor vehicle speed, wheel to
body position, lift/dive and steering position of the vehicle.
The controller then sends signals to each shock absorber
to independently adjust the damping level to provide the
optimum vehicle ride.
Autoride™also interacts with the tow/haul switch that,
when engaged, will provide additional control of the shock
absorbers. This additional control results in better ride
and handling characteristics when the vehicle is loaded or
towing a trailer. SeeTow/Haul Mode Light on page 3-52
for more information.
Trailer Recommendations
You must subtract your hitch loads from the Cargo
Weight Rating (CWR) for your vehicle. CWR is the
maximum weight of the load your vehicle can carry. It
doesn’t included the weight of the people inside. But you
cangure about 150 lbs. (68 kg) for each seat. The total
cargo load must not be more than your vehicle’s CWR.
Weigh your vehicle with the trailer attached, so that you
won’t go over the GVWR or GAWR. If you are using
a weight-distributing hitch, weigh the vehicle without the
spring bars in place.
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Making Turns
Notice:Making very sharp turns while trailering
could cause the trailer to come in contact with the
vehicle. Your vehicle could be damaged. Avoid
making very sharp turns while trailering.
When you’re turning with a trailer, make wider turns
than normal. Do this so your trailer won’t strike
soft shoulders, curbs, road signs, trees or other objects.
Avoid jerky or sudden maneuvers. Signal well in
advance.
Turn Signals When Towing a Trailer
The arrows on your instrument panel willash whenever
you signal a turn or lane change. Properly hooked up,
the trailer lamps will alsoash, telling other drivers
you’re about to turn, change lanes or stop.
When towing a trailer, the arrows on your instrument
panel willash for turns even if the bulbs on the trailer
are burned out. Thus, you may think drivers behind
you are seeing your signal when they are not. It’s
important to check occasionally to be sure the trailer
bulbs are still working.
Driving On Grades
Reduce speed and shift to a lower gearbeforeyou start
down a long or steep downgrade. If you don’t shift
down, you might have to use your brakes so much that
they would get hot and no longer work well.
You can tow in DRIVE (D). You may want to shift the
transmission to THIRD (3) or, if necessary, a lower
gear selection if the transmission shifts too often
(e.g., under heavy loads and/or hilly conditions).
You may also want to activate the tow/haul mode if the
transmission shifts too often. See“Tow/Haul Mode”
for more information.
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a lower
temperature than at normal altitudes. If you turn your
engine off immediately after towing at high altitude
on steep uphill grades, your vehicle may show signs
similar to engine overheating. To avoid this, let the
engine run while parked (preferably on level ground)
with the automatic transmission in PARK (P) for a
few minutes before turning the engine off. If you do get
the overheat warning, seeEngine Overheating on
page 5-29.
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The seven-wire harness contains the following trailer
circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn Signal
Brown: Taillamps
White: Ground
Light Green: Back-up Lamps
Red: Battery Feed
Dark Blue: Trailer Brake
Heavy-Duty Trailer Wiring Harness
Package
Your vehicle is equipped with the seven-wire trailer
towing harness. This harness with a seven-pin universal
trailer connector is attached to a bracket on the hitch
platform.
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The seven-wire harness contains the following trailer
circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn Signal
Brown: Taillamps
White: Ground
Light Green: Back-up Lamps
Red: Battery Feed
Dark Blue: Trailer Brake
If your trailer is equipped with electronic brakes, you
can get a jumper harness (electric trailer brake control)
with a trailer battery feed fuse from your dealer. This
harness and fuse should be installed by your dealer or a
qualied service center.
If you need to tow a light-duty trailer with a standard
four-way round pin connector, you can also get an
adapter.
Power Winches
If you wish to use a power winch on your vehicle, only
use it when your vehicle is stationary or anchored.
Step-Bumper Pad
Your vehicle has a rear step bumper with a rear step
pad at the center of the bumper.
If you will be using the
bumper to tow a trailer,
and your step-bumper has
three cutout circles you
must push out the center
cutout circle to install
the trailer ball.
If your step-bumper has only one cutout circle, you will
have to cut out the circle, then remove it to install
the trailer ball.
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Service............................................................5-3
Doing Your Own Service Work.........................5-3
Adding Equipment to the Outside of Your
Vehicle......................................................5-4
Fuel................................................................5-4
Gasoline Octane............................................5-4
Gasoline Specifications....................................5-4
California Fuel...............................................5-5
Additives.......................................................5-5
Fuel E-85 (85% Ethanol).................................5-6
Fuels in Foreign Countries...............................5-7
Filling Your Tank............................................5-7
Filling a Portable Fuel Container.....................5-10
Checking Things Under
the Hood....................................................5-10
Hood Release..............................................5-11
Engine Compartment Overview.......................5-12
Engine Oil...................................................5-16
Engine Air Cleaner/Filter................................5-21
Automatic Transmission Fluid.........................5-23
Engine Coolant.............................................5-26
Coolant Surge Tank Pressure Cap..................5-29Engine Overheating.......................................5-29
Cooling System............................................5-32
Engine Fan Noise.........................................5-37
Power Steering Fluid.....................................5-38
Windshield Washer Fluid................................5-39
Brakes........................................................5-40
Battery........................................................5-43
Jump Starting...............................................5-44
All-Wheel Drive..............................................5-49
Rear Axle.......................................................5-50
Four-Wheel Drive............................................5-51
Front Axle......................................................5-52
Bulb Replacement..........................................5-52
Halogen Bulbs..............................................5-53
Headlamps..................................................5-53
Front Turn Signal, Sidemarker and Daytime
Running Lamps.........................................5-54
Side Identification Marker Lamps.....................5-55
Roof Marker Lamps......................................5-55
Taillamps.....................................................5-57
Replacement Bulbs
.......................................5-59
Section 5 Service and Appearance Care
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A. Low-Beam Headlamp
B. High-Beam Headlamp
2. Pull the headlamp assembly out.
3. Unplug the electrical connector.
4. Turn the old bulb counterclockwise and remove it
from the headlamp assembly.
5. Put the new bulb into the assembly and turn it
clockwise until it is tight. Use care not to touch
the bulb with yourfingers or hands.
6. Plug in the electrical connector.
7. Put the headlamp assembly back into the vehicle.
Install and tighten the two pins.
Front Turn Signal, Sidemarker and
Daytime Running Lamps
A. Sidemarker Lamp
B. Retainer Clip
C. Front Turn Signal Lamp
D. Daytime Running Lamp
1. Remove the headlamp assembly as mentioned
previously.
2. Press the retainer clip, located behind the turn
signal housing, towards the outside of the vehicle.
3. Pull the turn signal housing out from the vehicle.
4. Press the locking release lever, turn the bulb socket
counterclockwise and remove it from the turn signal
housing.
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5. Remove the old bulb from the bulb socket.
6. Put the new bulb into the bulb socket. Use care not
to touch the bulb with yourfingers or hands.
7. Put the bulb socket into the turn signal housing and
turn it clockwise until it locks.
8. Put the turn signal housing back onto the vehicle
placing the hook and posts on the inner side into
the alignment holesfirst and then the outer side into
the retainer bracket. Push until you hear a click.
9. Put the headlamp assembly back into the vehicle.
Side Identication Marker Lamps
1. To expose the service slot, locate the lamp gasket
near the rear wheel, and pull back the edge.
2. Using aflat tool, push into the slot to release the
lamp housing.
3. Pull the housing out to expose the wiring harness
and connector.4. Unplug the lamp assembly harness from the
housing.
5. Unplug the lamp.
6. Put in a new lamp and snap it into the housing.
7. Reinstall the lamp housing.
Roof Marker Lamps
1. Remove the
two screws and
lift off the lens.
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