2006 GMC SIERRA hood open

The horn may chirp for 10 seconds before the alarm
goes off if the theft-deterrent system is activated using
the remote keyless entry transmitter and the driver’s door
is opened. If this occurs, you can turn off the alarm by
pressing unlock on the remote keyless entry transmitter
or by placing the key in the ignition and turning it to
START.
Here is how to avoid setting off the alarm by accident:
If you do not want to activate the theft-deterrent
system, the vehicle should be locked with the
door key after the doors are closed.
Always unlock a door with the remote keyless entry
transmitter.
If you set off the alarm by accident, turn off the alarm by
pressing unlock on the remote keyless entry transmitter
or by placing the key in the ignition and turning it to
START.
Testing the Alarm
The alarm can be tested by following these steps:
1. From inside the vehicle, activate the system by
locking the doors with the remote keyless entry
transmitter.
2. Wait for the security light to go out.
3. Unlock the door with the manual door lock and
open the door. This should set off the alarm.
4. Turn off the alarm by pressing unlock on the remote
keyless entry transmitter or by placing the key in
the ignition and turning it to START.
If the alarm does not sound when it should, but the
vehicle’s headlamps ash, check to see if the horn
works. The horn fuse may be blown. To replace the
fuse, seeInstrument Panel Fuse Block on page 5-124
andUnderhood Fuse Block on page 5-127.
If the alarm does not sound or the vehicle’s headlamps
do not ash, see your dealer for service.
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Engine Coolant Heater
In very cold weather, 0°F (−18°C) or colder, the engine
coolant heater can help. You will 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. Your vehicle may also have an internal
thermostat in the plug end of the cord. This will prevent
operation of the engine coolant heater when the
temperature is at or above 0°F (−18 C°) as noted on
the cord.
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 uid reservoir.
If you have a diesel engine, refer to diesel
supplement for location.
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 do not, 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 will be parking your
vehicle. The dealer can give you the best advice for that
particular area.
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Hood Release
To open the hood do the following:
1. Pull the handle with
this symbol on it. It is
located inside the
vehicle to the lower left
of the steering wheel.
2. Then go to the front of the vehicle and pull up on the
secondary hood release located near the center of
the grille.
3. Lift the hood.
Before closing the hood, be sure all the ller caps
are on properly. Then pull down the hood and close
it rmly.
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Engine Compartment Overview
When you open the hood on the 4.3L V6 engine, here is what you will see:
5-14

When you open the hood on the 5.3L V8 engine (4.8L and 6.0L V8 engines similar), here is what you will see:
5-16

When you open the hood on the 8.1L V8 engine, here is what you will see:
5-18

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.
SeeOverheated Engine Protection Operating
Mode (V8 Engines Only) on page 5-39for
information on driving to a safe place in an
emergency.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. SeeOverheated Engine Protection
Operating Mode (V8 Engines Only) on page 5-39for
information on driving to a safe place in an
emergency.
If No Steam Is Coming From Your
Engine
The ENGINE COOLANT HOT message, along with a
low coolant condition, can indicate a serious problem.
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. SeeTowing a Trailer on page 4-67.
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If you get the ENGINE COOLANT HOT message with
no sign of steam, try this for a minute or so:
1. If your air conditioner is on, turn it off.
2. Turn on your heater to full hot at the highest fan
speed and open the windows as necessary.
3. If you are in a traffic jam, shift to NEUTRAL (N);
otherwise, shift to the highest gear while
driving — DRIVE (D) or THIRD (3).
If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about 10 minutes.
If the warning does not come back on, you can drive
normally.
If the warning continues, pull over, stop, park, and fast
idle your vehicle right away.
If there is still no sign of steam and your vehicle is
equipped with an engine-driven cooling fan, push down
the accelerator until the engine speed is about twice as
fast as normal idle speed for at least three minutes while
you are parked.
If there is still no sign of steam and your vehicle is
equipped with an electric engine cooling fan, idle the
engine for three minutes while you are parked.
If you still have the warning, turn off the engine and get
everyone out of the vehicle until it cools down. Also,
see “Overheated Engine Protection Operating Mode”
later in this section.
You may decide not to lift the hood but to get service
help right away.Overheated Engine Protection
Operating Mode (V8 Engines Only)
If an overheated engine condition exists and the
REDUCED ENGINE POWER message is displayed, an
overheat protection mode which alternates ring groups
of cylinders helps prevent engine damage. In this mode,
you will notice a loss in power and engine performance.
This operating mode allows your vehicle to be driven to
a safe place in an emergency. Driving extended
miles (km) and/or towing a trailer in the overheat
protection mode should be avoided.
Notice:After driving in the overheated engine
protection operating mode, to avoid engine damage,
allow the engine to cool before attempting any repair.
The engine oil will be severely degraded. Repair the
cause of coolant loss, change the oil and reset the oil
life system. SeeEngine Oil (Gasoline Engine) on
page 5-20.
5-39