ignition GMC SIERRA 2004 Service Manual

Dome Lamps
The dome lamps will come on when you open a door.
You can also turn the dome lamps on by turning the
thumbwheel, located next to the exterior lamps control, all
the way up. In this position, the dome lamps will remain
on whether the doors are opened or closed.
E:You can use the dome override button, located
below the exterior lamps control, to set the dome lamps
to come on automatically, or remain off, when the
doors are opened. To turn the lamps off, press the
button to the in position. With the button in this position,
the dome lamps will remain off when the doors are
open. To return the lamps to automatic operation, press
the button again and return it to the out position.
Battery Run-Down Protection
This feature shuts off the dome, and reading lamps.
if they are left on for more than 10 minutes when the
ignition is off. The cargo lamp will shut off after
20 minutes. This will keep your battery from
running down.
Accessory Power Outlets
With accessory power outlets you can plug in auxiliary
electrical equipment such as a cellular telephone or
CB radio.
Your vehicle may have two accessory power outlets, or
may have one accessory power outlet located near
the cigarette lighter, if equipped. The cigarette lighter is
designed to ®t only in the receptacle to the right of
the accessory power outlet.
To use the outlet, lift the cover. When not using it,
always close the cover.
Certain power accessory plugs may not be compatible
to the accessory power outlet and could result in
blown vehicle or adapter fuses. If you experience a
problem, see your dealer for additional information on
the accessory power plugs.
Notice:Adding any electrical equipment to your
vehicle may damage it or keep other components
from working as they should. The repairs would not
be covered by your warranty. Check with your
dealer before adding electrical equipment.
When adding electrical equipment, be sure to follow the
proper installation instructions included with the
equipment.
3-20

Speedometer and Odometer
Your speedometer lets you see your speed in both
miles per hour (mph) and kilometers per hour (km/h).
Your odometer shows how far your vehicle has
been driven, in either miles (used in the United States)
or kilometers (used in Canada).
Trip Odometer
The trip odometer can tell you how far your vehicle has
been driven since you last set the trip odometer to zero.
Press the reset button to toggle between the trip
odometer and the regular odometer. Holding the reset
button for two seconds while the trip odometer is
displayed will reset it.
To display the odometer reading with the ignition off,
press the reset button.
Engine Hour Meter Display
The odometer can also display the number of hours the
engine has run. To display the hour meter, turn the
ignition off, press and hold the reset button for at least
four seconds. The hour meter will be displayed for
up to 30 seconds, or until the ignition is turned on.
Tachometer
Your tachometer displays the engine speed in
revolutions per minute (rpm).
Notice:If you operate the engine with the
tachometer in the shaded warning area, your vehicle
could be damaged, and the damages would not
be covered by your warranty. Do not operate
the engine with the tachometer in the shaded
warning area.
3-35

Passenger Air Bag Status Indicator
If your vehicle has the passenger sensing system
your rearview mirror will have a passenger air bag status
indicator.
When the ignition key is turned to RUN or START, the
passenger air bag status indicator will light ON and
OFF, or the symbol for on and off, for several seconds
as a system check. Then, after several more seconds,the status indicator will light either ON or OFF, or either
the on or off symbol to let you know the status of the
right front passenger's frontal air bag.
If the word ON or the on symbol is lit on the passenger
air bag status indicator, it means that the right front
passenger's frontal air bag is enabled (may in¯ate).
{CAUTION:
If the on indicator comes on when you have a
rear-facing child restraint installed in the right
front passenger's seat, it means that the
passenger sensing system has not turned off
the passenger's frontal air bag. A child in a
rear-facing child restraint can be seriously
injured or killed if the right front passenger's air
bag in¯ates. This is because the back of the
rear-facing child restraint would be very close
to the in¯ating air bag. Don't use a rear-facing
child restraint in the right front passenger's seat
unless the air bag has been turned off. Passenger Air Bag Status Indicator ± United States
Passenger Air Bag
Status Indicator
± Canada
3-40

Battery Warning Light
If this light is displayed
when the engine is
running, you may have a
problem with your charging
system.
The battery display will also stay on while the key is in
RUN until the engine is started.
If the light stays on after starting the engine it could
indicate a problem with the generator drive belt, or some
other charging system problem. Have it checked right
away. Driving with this light displayed could drain
your battery.
If you must drive a short distance with this light
displayed, it helps to turn off all your accessories, such
as the radio and the air conditioner.
Voltmeter Gage
When your engine is not
running, but the ignition is
in RUN, this gage
shows your battery's state
of charge in DC volts.
When the engine is running, the gage shows the
condition of the charging system. Readings between the
low and high warning zones indicate the normal
operating range.
Readings in the low warning zone may occur when a
large number of electrical accessories are operating in
the vehicle and the engine is left at an idle for an
extended period. This condition is normal since the
charging system is not able to provide full power
at engine idle. As engine speeds are increased, this
condition should correct itself as higher engine speeds
allow the charging system to create maximum power.
3-42

You can only drive for a short time with the reading in
either warning zone. If you must drive, turn off all
unnecessary accessories.
Readings in either warning zone indicate a possible
problem in the electrical system. Have the vehicle
serviced as soon as possible.
Up-Shift Light
This light is used on some
models with manual
transmissions.
The shift indicator light will show you when to shift to
the next highest gear, and will help you get the best fuel
economy.
Brake System Warning Light
With the ignition on, the brake system warning light will
¯ash when you set the parking brake. The light will
¯ash if the parking brake doesn't release fully. If you try
to drive with the parking brake engaged, a chime will
sound when the vehicle speed is greater than
3 mph (5 km/h).
Your vehicle's hydraulic brake system is divided into two
parts. If one part isn't working, the other part can still
work and stop you. For good braking, though, you need
both parts working well.
If the warning light comes on and a chime sounds there
could be a brake problem. Have your brake system
inspected right away.
3-43

This light should come on brie¯y when you turn the
ignition key to RUN. If it doesn't come on then, have it
®xed so it will be ready to warn you if there's a
problem.
If the light comes on while you are driving, pull off the
road and stop carefully. You may notice that the pedal is
harder to push. Or, the pedal may go closer to the
¯oor. It may take longer to stop. If the light is still on,
have the vehicle towed for service. See
Towing
Your Vehicle on page 4-53.
{CAUTION:
Your brake system may not be working
properly if the brake system warning light is
on. Driving with the brake system warning light
on can lead to an accident. If the light is still
on after you have pulled off the road and
stopped carefully, have the vehicle towed for
service. United States
Canada
3-44

Anti-Lock Brake System Warning
Light
With the anti-lock brake
system, this light will come
on when you start your
engine and may stay on for
several seconds.
That's normal. If the light doesn't come on then, have it
®xed so it will be ready to warn you if there is a
problem.
If the light stays on, or comes on when you're driving,
your vehicle needs service. You will also hear a
chime sound when the light is on steady. If the regular
brake system warning light isn't on, you still have
brakes, but you don't have anti-lock brakes. If the
regular brake system warning light is also on you don't
have anti-lock brakes and there's a problem with
your regular brakes. In addition to both lights, you will
also hear a chime sound on the ®rst occurrence of
a problem and each time the vehicle is shut off and then
restarted. See
Brake System Warning Light on
page 3-43.
Traction Off Light
If you have the Traction
Assist System, this light
should come on brie¯y
when you turn the ignition
to RUN.
If the light doesn't come on then, the system may
require service; have it ®xed so it will be there to warn
you if the system is turned off.
If the light stays on, or comes on when you're driving,
there may be a problem with your Traction Assist
System and your vehicle may need service. When this
light is on, the system will not limit wheel spin. Adjust
your driving accordingly.
3-45

It also provides an indicator of how hard your vehicle is
working. During a majority of the operation, the gage
will read 210ÉF (100ÉC) or less. If you are pulling a load
or going up hills, it is normal for the temperature to
¯uctuate and approach the 250ÉF (122ÉC) mark. If the
gage reaches the 260ÉF (125ÉC) mark, it indicates
that the cooling system is working beyond its capacity.
See
Engine Overheating on page 5-36.
Transmission Temperature Gage
Your vehicle may be equipped with a transmission
temperature gage.When your ignition is on, the gage shows the
temperature of the transmission ¯uid. The normal
operating range is from 100ÉF (38ÉC) to about
265ÉF (130ÉC).
At approximately 265ÉF (130ÉC), the driver information
center will display a TRANSMISSION HOT message
and the transmission will enter a transmission protection
mode. When the transmission enters the protection
mode, you may notice a change in the transmission
shifting patterns. The transmission will return to normal
shifting patterns when the transmission ¯uid temperature
falls below 260ÉF (127ÉC).
See
Driver Information Center (DIC) on page 3-55for
further information.
United States
Canada
3-47

Malfunction Indicator Lamp
Check Engine Light
Your vehicle is equipped
with a computer which
monitors operation of the
fuel, ignition and emission
control systems.
This system is called OBD II (On-Board
Diagnostics-Second Generation) and is intended to
assure that emissions are at acceptable levels for the
life of the vehicle, helping to produce a cleaner
environment. The Check Engine light comes on to
indicate that there is a problem and service is required.
Malfunctions often will be indicated by the system
before any problem is apparent. This may prevent more
serious damage to your vehicle. This system is also
designed to assist your service technician in correctly
diagnosing any malfunction.
Notice:If you keep driving your vehicle with this
light on, after a while, your emission controls
may not work as well, your fuel economy may not
be as good and your engine may not run as
smoothly. This could lead to costly repairs that may
not be covered by your warranty.
Notice:Modi®cations made to the engine,
transmission, exhaust, intake or fuel system of your
vehicle or the replacement of the original tires
with other than those of the same Tire Performance
Criteria (TPC) can affect your vehicle's emission
controls and may cause this light to come on.
Modi®cations to these systems could lead to costly
repairs not covered by your warranty. This may
also result in a failure to pass a required Emission
Inspection/Maintenance test.
3-49

This light should come on, as a check to show you it is
working, when the ignition is on and the engine is
not running. If the light does not come on, have it
repaired. This light will also come on during a
malfunction in one of two ways:
·Light FlashingÐ A mis®re condition has been
detected. A mis®re increases vehicle emissions
and may damage the emission control system on
your vehicle. Diagnosis and service may be
required.
·Light On SteadyÐ An emission control system
malfunction has been detected on your vehicle.
Diagnosis and service may be required.
If the Light is Flashing
The following may prevent more serious damage to
your vehicle:
·Reducing vehicle speed.
·Avoiding hard accelerations.
·Avoiding steep uphill grades.
·If you are towing a trailer, reduce the amount of
cargo being hauled as soon as it is possible.
If the light stops ¯ashing and remains on steady, see ªIf
the Light Is On Steadyº following.If the light continues to ¯ash, when it is safe to do so,
stop the vehicle.Find a safe place to park your vehicle.
Turn the key off, wait at least 10 seconds and restart
the engine. If the light remains on steady, see
ªIf the Light Is On Steadyº following. If the light is still
¯ashing, follow the previous steps, and see your dealer
for service as soon as possible.
If the Light Is On Steady
You may be able to correct the emission system
malfunction by considering the following:
Did you recently put fuel into your vehicle?
If so, reinstall the fuel cap, making sure to fully install
the cap. See
Filling Your Tank on page 5-7. The
diagnostic system can determine if the fuel cap has
been left off or improperly installed. A loose or missing
fuel cap will allow fuel to evaporate into the atmosphere.
A few driving trips with the cap properly installed
should turn the light off.
Did you just drive through a deep puddle of water?
If so, your electrical system may be wet. The condition
will usually be corrected when the electrical system
dries out. A few driving trips should turn the light off.
3-50