headlamp GMC SONOMA 2003 User Guide

What’s beyond the hill? Is there a cliff, an
embankment, a drop-off, a fence? Get out and walk
the hill if you don’t know. It’s the smart way to
nd out.
Is the hill simply too rough? Steep hills often have
ruts, gullies, troughs and exposed rocks because
they are more susceptible to the effects of erosion.
Driving Uphill
Once you decide you can safely drive up the hill, you
need to take some special steps.
Use a low gear and get arm grip on the steering
wheel.
Get a smooth start up the hill and try to maintain
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
nd another route.
{CAUTION:
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 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.
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Driving at Night
Night driving is more dangerous than day driving. One
reason is that some drivers are likely to be impaired—by
alcohol or drugs, with night vision problems, or by fatigue.
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.
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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.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.
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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....................................5-5
California Fuel...............................................5-5
Additives.......................................................5-5
Fuels in Foreign Countries...............................5-6
Filling Your Tank............................................5-6
Filling a Portable Fuel Container.......................5-8
Checking Things Under
the Hood......................................................5-8
Hood Release................................................5-9
Engine Compartment Overview.......................5-10
Engine Oil...................................................5-13
Engine Air Cleaner/Filter................................5-18
Automatic Transmission Fluid
.........................5-20
Manual Transmission Fluid
.............................5-23
Hydraulic Clutch
...........................................5-24Engine Coolant.............................................5-25
Radiator Pressure Cap..................................5-27
Engine Overheating.......................................5-28
Cooling System............................................5-30
Engine Fan Noise.........................................5-36
Power Steering Fluid.....................................5-37
Windshield Washer Fluid................................5-38
Brakes........................................................5-39
Battery........................................................5-42
Jump Starting...............................................5-43
Rear Axle.......................................................5-47
Four-Wheel Drive............................................5-48
Front Axle......................................................5-49
Bulb Replacement..........................................5-50
Halogen Bulbs..............................................5-50
Headlamps..................................................5-50
One-Piece Front Turn Signal Lamps................5-52
Two-Piece Front Turn Signal Lamps................5-53
Center High-Mounted Stoplamp (CHMSL).........5-54
Taillamps.....................................................5-55
Replacement Bulbs.......................................5-55
Section 5 Service and Appearance Care
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Windshield Wiper Blade Replacement..............5-56
Tires..............................................................5-58
Inflation–Tire Pressure................................5-58
Tire Inspection and Rotation...........................5-60
When It Is Time for New Tires.......................5-61
Buying New Tires.........................................5-62
Uniform Tire Quality Grading..........................5-63
Wheel Alignment and Tire Balance..................5-64
Wheel Replacement......................................5-65
Tire Chains..................................................5-66
If a Tire Goes Flat........................................5-67
Changing a Flat Tire.....................................5-68
Compact Spare Tire......................................5-78
Appearance Care............................................5-79
Cleaning the Inside of Your Vehicle.................5-79
Care of Safety Belts......................................5-82
Weatherstrips...............................................5-82
Cleaning the Outside of Your Vehicle..............5-82Sheet Metal Damage.....................................5-85
Finish Damage.............................................5-85
Underbody Maintenance................................5-85
Chemical Paint Spotting.................................5-85
GM Vehicle Care/Appearance Materials...........5-86
Vehicle Identification......................................5-87
Vehicle Identification Number (VIN).................5-87
Service Parts Identification Label.....................5-88
Electrical System............................................5-88
Add-On Electrical Equipment..........................5-88
Headlamps..................................................5-88
Windshield Wiper Fuses................................5-88
Power Windows and Other Power Options.......5-88
Fuses and Circuit Breakers
............................5-89
Capacities and Specifications
..........................5-94
Capacities and Specifications
.........................5-95
Normal Maintenance Replacement Parts
..........5-96
Section 5 Service and Appearance Care
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Bulb Replacement
SeeReplacement Bulbs on page 5-55for the proper
types of bulbs to use. For any bulb changing procedure
not listed in this section, contact your GM dealer’s
service department.
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
One-Piece Composite Headlamp
System
1. Open the hood.
2. Remove the black retainer clips by lifting up.
3. Pull the headlamp assembly out.
4. Unplug the electrical connector.
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5. Turn the bulb assembly counterclockwise to
remove it from the headlamp assembly.
6. Put the new bulb into the bulb assembly and
reinstall it in the headlamp assembly by turning
it clockwise until it is tight.
7. Plug in the electrical connector.
8. Put the headlamp assembly back into the vehicle.
9. Install the two retaining clips.
10. Close the hood.
Two-Piece Composite Headlamp
System
1. Open the hood.
2. Remove the black retainer clips by lifting up.
3. Unplug the electrical connector.
4. Pull the headlamp lens assembly out.
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5. Turn the bulb assembly counterclockwise to remove
it from the headlamp assembly.
6. Put the new bulb into the bulb assembly and
reinstall it in the headlamp assembly by turning
it clockwise until it is tight.
7. Plug in the electrical connector.
8. Put the headlamp lens assembly back into the
vehicle.
9. Install the two retaining clips.
10. Close the hood.
One-Piece Front Turn Signal Lamps
1. Remove the headlamp assembly as shown in
″One-Piece Composite Headlamp System″
underHeadlamps on page 5-50.
2. Twist the bulb socket
counterclockwise
to remove it from the
headlamp assembly.
3. Pull the bulb straight out to remove it from the
socket.
4. Push the new bulb into the socket until it snaps
into place.
5. Put the bulb socket into the lamp assembly and
twist it clockwise until it is tight.
6. Put the headlamp assembly back into the vehicle.
7. Install the two retaining clips.
8. Close the hood.
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Two-Piece Front Turn Signal Lamps
1. Remove the headlamp assembly as shown in
″Two-Piece Composite Headlamp System″
underHeadlamps on page 5-50.
2. Locate the locking
tabs on the assembly.
Squeeze the tabs
together and push that
end of the assembly
out while holding
the tabs. The assembly
will swing out.3. Unplug the electrical connector.
4. Turn the harness bulb socket counterclockwise to
remove it. Pull the bulb straight out to remove it
from the socket.
5. Push the new bulb into the socket until it snaps
into place.
6. Put the socket into the lamp assembly and turn it
clockwise until it is tight.
7. To reinstall the assembly, snap the outboard end of
the lamp assembly back into the vehicle. Then
swing the assembly in and snap it into place.
8. Install the two retaining clips.
9. Close the hood.
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