2003 GMC YUKON headlamp

Ease up on your speed as you approach the top of
the hill.
Attach aag to the vehicle to make you more
visible to approaching traffic on trails or hills.
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.
{CAUTION:
Driving to the top (crest) of a hill at full 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 youshoulddo:
Push the brake pedal to stop the vehicle and keep
it from rolling backwards. Also, apply the parking
brake.
If your engine is still running, shift the transmission
to REVERSE (R), release the parking brake, and
slowly back down the hill in REVERSE (R).
If your engine has stopped running, you’ll need to
restart it. With the brake pedal pressed and the
parking brake still applied, shift the transmission to
PARK (P) and restart the engine. Then, shift to
REVERSE (R), release the parking brake, and
slowly back down the hill as straight as possible in
REVERSE (R).
As you are backing down the hill, put your left hand
on the steering wheel at the 12 o’clock position.
This way, you’ll be able to tell if your wheels
are straight and maneuver as you back down. It’s
best that you back down the hill with your
wheels straight rather than in the left or right
direction. Turning the wheel too far to the left or
right will increase the possibility of a rollover.
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Here are some tips on night driving.
Drive defensively.
Don’t drink and drive.
Adjust your inside rearview mirror to reduce the
glare from headlamps behind you.
Since you can’t see as well, you may need to slow
down and keep more space between you and
other vehicles.
Slow down, especially on higher speed roads. Your
headlamps can light up only so much road ahead.
In remote areas, watch for animals.
If you’re tired, pull off the road in a safe place
and rest.
No one can see as well at night as in the daytime. But
as we get older these differences increase. A
50-year-old driver may require at least twice as much
light to see the same thing at night as a 20-year-old.
What you do in the daytime can also affect your
night vision. For example, if you spend the day in bright
sunshine you are wise to wear sunglasses. Your
eyes will have less trouble adjusting to night. But if
you’re driving, don’t wear sunglasses at night. They may
cut down on glare from headlamps, but they also
make a lot of things invisible.You can be temporarily blinded by approaching
headlamps. It can take a second or two, or even several
seconds, for your eyes to re-adjust to the dark. When
you are faced with severe glare (as from a driver
who doesn’t lower the high beams, or a vehicle with
misaimed headlamps), slow down a little. Avoid staring
directly into the approaching headlamps.
Keep your windshield and all the glass on your vehicle
clean—inside and out. Glare at night is made much
worse by dirt on the glass. Even the inside of the glass
can build up alm caused by dust. Dirty glass makes
lights dazzle andash more than clean glass would,
making the pupils of your eyes contract repeatedly.
Remember that your headlamps light up far less of a
roadway when you are in a turn or curve. Keep
your eyes moving; that way, it’s easier to pick out dimly
lighted objects. Just as your headlamps should be
checked regularly for proper aim, so should your eyes
be examined regularly. Some drivers suffer from
night blindness—the inability to see in dim light—and
aren’t even aware of it.
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Driving Through Flowing Water
{CAUTION:
Flowing or rushing water creates strong
forces. If you try to drive throughflowing
water, as you might at a low water crossing,
your vehicle can be carried away. As little as
six inches offlowing water can carry away a
smaller vehicle. If this happens, you and other
vehicle occupants could drown. Don’t ignore
police warning signs, and otherwise be very
cautious about trying to drive throughflowing
water.
Some Other Rainy Weather Tips
Turn on your low-beam headlamps–not just your
parking lamps–to help make you more visible to
others.
Besides slowing down, allow some extra following
distance. And be especially careful when you
pass another vehicle. Allow yourself more clear
room ahead, and be prepared to have your
view restricted by road spray.
Have good tires with proper tread depth. SeeTires
on page 5-60.
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{CAUTION:
Snow can trap exhaust gases under your
vehicle. This can cause deadly CO (carbon
monoxide) gas to get inside. CO could
overcome you and kill you. You can’t see it or
smell it, so you might not know it is in your
vehicle. Clear away snow from around the
base of your vehicle, especially any that is
blocking your exhaust pipe. And check around
again from time to time to be sure snow
doesn’t collect there.
Open a window just a little on the side of the
vehicle that’s away from the wind. This will
help keep CO out.Run your engine only as long as you must. This saves
fuel. When you run the engine, make it go a little
faster than just idle. That is, push the accelerator
slightly. This uses less fuel for the heat that you get and
it keeps the battery charged. You will need a
well-charged battery to restart the vehicle, and possibly
for signaling later on with your headlamps. Let the
heater run for a while.
Then, shut the engine off and close the window almost
all the way to preserve the heat. Start the engine
again and repeat this only when you feel really
uncomfortable from the cold. But do it as little as
possible. Preserve the fuel as long as you can. To help
keep warm, you can get out of the vehicle and do
some fairly vigorous exercises every half hour or so until
help comes.
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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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2003 - Yukon/Yukon XL

Halogen Bulbs
{CAUTION:
Halogen bulbs have pressurized gas inside
and can burst if you drop or scratch the bulb.
You or others could be injured. Be sure to read
and follow the instructions on the bulb
package.
Headlamps
1. Your vehicle is equipped with two pins, remove the
two pins on the top of the headlamp assembly. To
remove the pins, turn the outer pin outward and
pull it straight up. To remove the inner pin, turn it in
and pull it straight up.
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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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