2004 GMC SONOMA hood open

Notice:Your engine is designed to work with the
electronics in your vehicle. If you add electrical
parts or accessories, you could change the way the
engine operates. Before adding electrical equipment,
check with your dealer. If you do not, your engine
might not perform properly.
Engine Speed Control
Your vehicle is equipped with an engine overspeed
control that shuts the fuel off when the engine reaches
5,600 rpm.
Engine Coolant Heater
Your vehicle may be equipped with this feature.
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. At
temperatures above 32°F (0°C), 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 in the engine compartment behind the
underhood fuse block on the driver’s side of the
vehicle.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 re. You could be seriously
injured. Plug the cord into a properly grounded
three-prong 110-volt AC outlet. If the cord will
not 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.
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Dome Lamp
The dome lamp will come on when you open either
front door.
You can also turn the dome lamps on by turning the
instrument panel brightness thumbwheel, located next to
the exterior lamps control, all the way up to the second
notch. In this position, the dome lamps will remain
on whether a door is opened or closed.
You can use the DOME OVERRIDE button, located
below the exterior lamps control, to set the dome lamps
to come on automatically when either front door is
opened, or to remain off. To turn the lamps off, press
the button in. With the button in, the dome lamps will
remain off when either front door is opened. To return
the lamps to automatic operation, press the button
again and return it to the out position. With the button in
this position, the dome lamps will come on when you
open either front door. This will override the illuminated
entry feature, unless you use your remote keyless
entry transmitter (if equipped) to unlock the vehicle.
Battery Rundown Protection
This feature shuts off the dome, courtesy, vanity,
reading, glove box, cargo and underhood lamps if they
are left on for more than 20 minutes when the ignition
is off. This will keep your battery from running down.
If the battery rundown protection shuts off the interior
lamps, it may be necessary to do one of the following to
return it to normal operation:
•Shut off all lamps and close all doors, or
•turn the ignition key to RUN.
Accessory Power Outlets
Your vehicle may be equipped with an accessory power
outlet.
With accessory power outlets you can plug in auxiliary
electrical equipment such as a cellular telephone or
CB radio.
There may be an accessory power outlet located
near the center of the vehicle on the lower part of the
instrument panel. A small cap must be pulled down
to access an accessory power outlet. When not using
an outlet be sure to cover it with the protective cap.
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Checking Things Under
the Hood
{CAUTION:
Things that burn can get on hot engine parts
and start a re. These include liquids like fuel,
oil, coolant, brake uid, windshield washer and
other uids, and plastic or rubber. You or
others could be burned. Be careful not to drop
or spill things that will burn onto a hot engine.
Hood Release
To open the hood, do the following:
1. Pull the handle located
inside the vehicle on
the lower left side
of the instrument
panel.
2. Release the secondary latch located under the front
edge of the hood.
3. Lift the hood.
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Engine Compartment Overview
When you open the hood on your engine, you’ll see:
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Radiator Pressure Cap
Notice:If the pressure cap is not tightly installed,
coolant loss and possible engine damage may
occur. Be sure the cap is properly and tightly
secured.
Engine Overheating
You will find a coolant temperature gage on your
vehicle’s instrument panel. SeeEngine Coolant
Temperature Gage on page 3-28.
If Steam Is Coming From Your Engine
{CAUTION:
Steam from an overheated engine can burn
you badly, even if you just open the hood. Stay
away from the engine if you see or hear steam
coming from it. Just turn it off and get
everyone away from the vehicle until it cools
down. Wait until there is no sign of steam or
coolant before you open the hood.
If you keep driving when your engine is
overheated, the liquids in it can catch re. You
or others could be badly burned. Stop your
engine if it overheats, and get out of the
vehicle until the engine is cool.
Notice:If your engine catches re because you
keep driving with no coolant, your vehicle can
be badly damaged. The costly repairs would not be
covered by your warranty.
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If No Steam Is Coming From Your
Engine
If you get an engine overheat warning but see or hear
no steam, the problem may not be too serious.
Sometimes the engine can get a little too hot when you:
•Climb a long hill on a hot day.
•Stop after high-speed driving.
•Idle for long periods in traffic.
•Tow a trailer. See “Driving on Grades” under
Towing a Trailer on page 4-55.
If you get the overheat warning with no sign of steam,
try this for a minute or so:
1. In heavy traffic, let the engine idle in NEUTRAL
while stopped. If it is safe to do so, pull off the
road, shift to PARK (P) or NEUTRAL and let the
engine idle.
2. Turn on your heater to full hot at the highest fan
speed and open the window as necessary.If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about 10 minutes.
If the warning doesn’t come back on, you can drive
normally.
If the warning continues, pull over, stop, and park your
vehicle right away.
If there’s still no sign of steam, idle the engine for three
minutes while you’re parked. Push down the accelerator
until the engine speed is about twice as fast as
normal idle speed for at least three minutes while you’re
parked. If you still have the warning,turn off the
engine and get everyone out of the vehicleuntil it
cools down.
You may decide not to lift the hood but to get service
help right away.
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2. Get the vehicles close enough so the jumper cables
can reach, but be sure the vehicles aren’t touching
each other. If they are, it could cause a ground
connection you don’t want. You wouldn’t be able to
start your vehicle, and the bad grounding could
damage the electrical systems.
To avoid the possibility of the vehicles rolling, set
the parking brake firmly on both vehicles involved in
the jump start procedure. Put an automatic
transmission in PARK (P) or a manual transmission
in NEUTRAL before setting the parking brake. If
you have a four-wheel-drive vehicle, be sure
the transfer case is not in NEUTRAL (N).
Notice:If you leave your radio or other accessories
on during the jump starting procedure, they could
be damaged. The repairs would not be covered
by your warranty. Always turn off your radio and
other accessories when jump starting your vehicle.
3. Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter or in the accessory power outlets. Turn off
the radio and all lamps that aren’t needed. This will
avoid sparks and help save both batteries. And it
could save your radio!4. Open the hoods and locate the batteries. Find the
positive (+) and negative (-) terminal locations on
each vehicle. SeeEngine Compartment Overview
on page 5-12for more information on location of the
battery.
{CAUTION:
Using a match near a battery can cause battery
gas to explode. People have been hurt doing
this, and some have been blinded. Use a
ashlight if you need more light.
Be sure the batteries have enough water. You
do not need to add water to the ACDelco
®
battery (or batteries) installed in your new
vehicle. But if a battery has ller caps, be sure
the right amount of uid is there. If it is low,
add water to take care of that rst. If you do
not, explosive gas could be present.
Battery uid contains acid that can burn you.
Do not get it on you. If you accidentally get it
in your eyes or on your skin, ush the place
with water and get medical help immediately.
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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.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.
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