For vehicles with a Driver Information Center (DIC), see
DIC Warnings and Messages on page 4-44for all
brake related DIC messages.
StabiliTrak®Indicator Light
For vehicles with the
StabiliTrak®system,
this light comes on or
flashes, according to the
description table for
the StabiliTrak system.
For more information, seeStabiliTrak
®System on
page 5-5.
Three chimes sound if the light turns on and one chime
if the light turns off.
If this light remains on steady, the vehicle needs to be
taken in for service.
Engine Coolant Temperature Gage
This gage shows the engine coolant temperature.
It also provides an indicator of how hard the vehicle is
working. During a majority of the operation, the gage will
read 100°C (210°F) or less. If the vehicle is pulling a load
or going up hills, it is normal for the temperature to
fluctuate and approach the 122°C (250°F) mark. If the
gage reaches the 125°C (260°F) mark, it indicates that
the cooling system is working beyond its capacity.
SeeEngine Overheating on page 6-35.
United StatesCanada
4-29
Tire Pressure Light
For vehicles with a tire
pressure monitoring
system, this light comes
on briefly when the engine
is started. It provides
information about tire
pressures and the Tire
Pressure Monitoring
System.
When the Light is On Steady
This indicates that one or more of the tires are
significantly underinflated.
A tire pressure message in the Driver Information
Center (DIC), can accompany the light. SeeDriver
Information Center (DIC) on page 4-36for more
information. Stop and check the tires as soon as it is
safe to do so. If underinflated, inflate to the proper
pressure. SeeIn ation - Tire Pressure on page 6-68
for more information.
When the Light Flashes First and Then is
On Steady
This indicates that there may be a problem with the Tire
Pressure Monitor System. The light flashes for about
a minute and stays on steady for the remainder of
the ignition cycle. This sequence repeats with every
ignition cycle. SeeTire Pressure Monitor Operation on
page 6-72for more information.
Malfunction Indicator Lamp
Check Engine Light
A computer system called OBD II (On-Board
Diagnostics-Second Generation) monitors operation
of the fuel, ignition, and emission control systems.
It ensures that emissions are at acceptable levels for
the life of the vehicle, helping to produce a cleaner
environment.
This light should come on
when the ignition is on, but
the engine is not running,
as a check to show it
is working. If it does not,
have the vehicle serviced
by your dealer/retailer.
4-30
Oil Pressure Light
{WARNING:
Do not keep driving if the oil pressure is low. The
engine can become so hot that it catches fire.
Someone could be burned. Check the oil as soon
as possible and have the vehicle serviced.
Notice:Lack of proper engine oil maintenance can
damage the engine. The repairs would not be
covered by the vehicle warranty. Always follow the
maintenance schedule in this manual for changing
engine oil.This light comes on briefly while starting the engine.
If it does not, have the vehicle serviced by your
dealer/retailer. If the system is working normally the
indicator light then goes off.
If the light comes on and stays on, it means that oil is
not flowing through the engine properly. The vehicle
could be low on oil and it might have some other system
problem.
Security Light
For information regarding
this light and the vehicle’s
security system, see
PASS-Key
®III+ Electronic
Immobilizer Operation
on page 3-20.
4-34
SERVICE TRANSMISSION
This message displays when there is a problem with the
transmission. See your dealer/retailer for service.
SERVICE VEHICLE SOON
This message displays when a non-emissions related
malfunction occurs. Have the vehicle serviced by
your dealer/retailer as soon as possible.
STABILITRAK NOT READY
If your vehicle has StabiliTrak, this message may display
and the StabiliTrak indicator light on the instrument
panel cluster may be on after first driving the vehicle
and exceeding 32 km/h (20 mph) for 30 seconds.
The StabiliTrak system is not functional until the light
has turned off. SeeStabiliTrak
®System on page 5-5for
more information.
STABILITRAK OFF
If your vehicle has StabiliTrak, this message displays
when you turn off StabiliTrak, or when the stability control
has been automatically disabled. To limit wheel spin and
realize the full benefits of the stability enhancement
system, you should normally leave StabiliTrak on.However, you should turn StabiliTrak off if your vehicle
gets stuck in sand, mud, ice, or snow and you want to
rock your vehicle to attempt to free it, or if you are driving
in extreme off-road conditions and require more wheel
spin. SeeIf Your Vehicle is Stuck in Sand, Mud, Ice, or
Snow on page 5-18. To turn the StabiliTrak system on or
off, seeStabiliTrak
®System on page 5-5.
There are several conditions that can cause this
message to appear.
•One condition is overheating, which could occur if
StabiliTrak activates continuously for an extended
period of time.
•The message also displays if the brake system
warning light is on. SeeBrake System Warning
Light on page 4-27.
•The message could display if the stability system
takes longer than usual to complete its diagnostic
checks due to driving conditions.
•The message displays if an engine or vehicle
related problem has been detected and the vehicle
needs service. See your dealer/retailer.
The message turns off as soon as the conditions that
caused the message to be displayed are no longer
present.
4-50
STARTING DISABLED SERVICE
THROTTLE
This message displays if the starting of the engine is
disabled due to the electronic throttle control system.
Have your vehicle serviced by your dealer/retailer
immediately.
This message only appears while the ignition is in
ON/RUN, and will not disappear until the problem is
resolved.
This message cannot be acknowledged.
TIGHTEN GAS CAP
This message may display and a chime may be heard
along with the check engine light on the instrument
panel cluster if the vehicle’s fuel cap is not tightened
properly. SeeMalfunction Indicator Lamp on page 4-30.
Reinstall the fuel cap fully. SeeFilling the Tank on
page 6-10. The diagnostic system can determine if
the fuel cap has been left off or improperly installed.
A loose or missing fuel cap allows fuel to evaporate
into the atmosphere. A few driving trips with the
cap properly installed should turn this light and
message off.
TIRE LEARNING ACTIVE
If your vehicle has the Tire Pressure Monitor
System (TPMS), this message displays when the
system is re-learning the tire positions on your vehicle.
SeeDIC Operation and Displays on page 4-37for more
information. The tire positions must be re-learned after
rotating the tires or after replacing a tire or sensor. See
Tire Inspection and Rotation on page 6-75,Tire Pressure
Monitor System on page 6-70, andIn ation - Tire
Pressure on page 6-68for more information.
TRACTION CONTROL OFF
If your vehicle has StabiliTrak, this message displays
when the Traction Control System (TCS) is turned
off. Adjust your driving accordingly. SeeStabiliTrak
®
System on page 5-5for more information.
4-51
Press and hold the
StabiliTrak button located
on the instrument panel
for more than five seconds
to turn off StabiliTrak
and part of the traction
control system.
The StabiliTrak light comes
on the instrument panel
cluster when the system is
turned off or requires
service.
For more information, seeStabiliTrak
®Indicator Light
on page 4-29.For your safety, the system can only be disabled when
the vehicle speed is less than 20 mph (32 km/h).
Three chimes will be heard and the StabiliTrak light
comes on.
To turn on the StabiliTrak system, press the StabiliTrak
button again. StabiliTrak will automatically turn back on
when the vehicle speed exceeds 20 mph (32 km/h). One
chime is heard and the StabiliTrak light will turn off.
When the StabiliTrak system has been turned off,
system noises may still be heard as a result of
the brake-traction control coming on.
It is recommended to leave the system on for normal
driving conditions, but it may be necessary to turn
the system off if the vehicle is stuck in sand, mud, ice or
snow, and you want to “rock” the vehicle to attempt to
free it. SeeIf Your Vehicle is Stuck in Sand, Mud, Ice, or
Snow on page 5-18.
5-6
If the vehicle has the 4.8L V8 engine (VIN Code A),
the 5.3L V8 engine (VIN Code 4), or the 6.0L V8 engine
(VIN Code G) and the N15 flexible fuel option, you can
use either regular unleaded gasoline or ethanol fuel
containing up to 85% ethanol (E85). SeeFuel E85
(85% Ethanol) on page 6-8. For all other gasoline
engines, use only regular unleaded gasoline.
Gasoline Octane
Use regular unleaded gasoline with a posted octane
rating of 87 or higher. If the octane rating is less than 87,
an audible knocking noise, commonly referred to as spark
knock, might be heard when driving. If this occurs, use a
gasoline rated at 87 octane or higher as soon as possible.
If heavy knocking is heard when using gasoline rated at
87 octane or higher, the engine needs service.
Gasoline Speci cations
At a minimum, gasoline should meet ASTM specification
D 4814 in the United States or CAN/CGSB-3.5 or 3.511 in
Canada. Some gasolines contain an octane-enhancing
additive called methylcyclopentadienyl manganese
tricarbonyl (MMT). We recommend against the use of
gasolines containing MMT. SeeAdditives on page 6-7
for additional information.
California Fuel
If the vehicle is certified to meet California Emissions
Standards, it is designed to operate on fuels that meet
California specifications. See the underhood emission
control label. If this fuel is not available in states adopting
California emissions standards, the vehicle will operate
satisfactorily on fuels meeting federal specifications, but
emission control system performance might be affected.
The malfunction indicator lamp could turn on and the
vehicle might fail a smog-check test. SeeMalfunction
Indicator Lamp on page 4-30. If this occurs, return to your
authorized dealer/retailer for diagnosis. If it is determined
that the condition is caused by the type of fuel used,
repairs might not be covered by the vehicle warranty.
6-6
Additives
To provide cleaner air, all gasolines in the United States
are now required to contain additives that help prevent
engine and fuel system deposits from forming, allowing
the emission control system to work properly. In most
cases, nothing should have to be added to the fuel.
However, some gasolines contain only the minimum
amount of additive required to meet U.S. Environmental
Protection Agency regulations. To help keep fuel injectors
and intake valves clean, or if the vehicle experiences
problems due to dirty injectors or valves, look for gasoline
that is advertised as TOP TIER Detergent Gasoline.
For customers who do not use TOP TIER Detergent
Gasoline regularly, one bottle of GM Fuel System
Treatment PLUS, added to the fuel tank at every engine
oil change, can help clean deposits from fuel injectors
and intake valves. GM Fuel System Treatment PLUS
is the only gasoline additive recommended by
General Motors.
Also, your dealer/retailer has additives that will help
correct and prevent most deposit-related problems.Gasolines containing oxygenates, such as ethers and
ethanol, and reformulated gasolines might be available in
your area. We recommend that you use these gasolines,
if they comply with the specifications described earlier.
However, E85 (85% ethanol) and other fuels containing
more than 10% ethanol must not be used in vehicles that
were not designed for those fuels.
Notice:This vehicle was not designed for fuel that
contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in the fuel
system and also damage plastic and rubber parts.
That damage would not be covered under the
vehicle warranty.
Some gasolines that are not reformulated for low
emissions can contain an octane-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. We recommend against
the use of such gasolines. Fuels containing MMT can
reduce the life of spark plugs and the performance
of the emission control system could be affected.
The malfunction indicator lamp might turn on. If this
occurs, return to your dealer/retailer for service.
6-7