Emissions Inspection and
Maintenance Programs
Some state/provincial and local governments have or
might begin programs to inspect the emission control
equipment on the vehicle. Failure to pass this inspection
could prevent getting a vehicle registration.
Here are some things to know to help the vehicle pass
an inspection:
The vehicle will not pass this inspection if the check
engine light is on with the engine running, or if the
key is in ON/RUN and the light is not on.
The vehicle will not pass this inspection if the OBD II
(on-board diagnostic) system determines that critical
emission control systems have not been completely
diagnosed by the system. The vehicle would be
considered not ready for inspection. This can happen
if the battery has recently been replaced or if the
battery has run down. The diagnostic system is
designed to evaluate critical emission control
systems during normal driving. This can take several
days of routine driving. If this has been done and the
vehicle still does not pass the inspection for lack of
OBD II system readiness, your dealer/retailer can
prepare the vehicle for inspection.
Oil Pressure Gage (US-Canada)
For vehicles with an engine oil pressure gage, it shows
the engine oil pressure in psi (pounds per square inch)
when the engine is running. Canadian vehicles indicate
pressure in kPa (kilopascals).
Oil pressure can vary with engine speed, outside
temperature and oil viscosity, but if readings are outside
the normal operating range, the oil pressure light
comes on. SeeOil Pressure Light on page 3-49for
more information.United States
Canada
3-48
A reading outside the normal operating range can be
caused by a dangerously low oil level or some other
problem causing low oil pressure. Check the vehicle’s oil
as soon as possible. See “OIL PRESSURE LOW” under
DIC Warnings and Messages on page 3-66andEngine
Oil on page 5-17.
{CAUTION:
Do not keep driving if the oil pressure is low.
The engine can become so hot that it catches re.
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.
Oil Pressure Light
{CAUTION:
Do not keep driving if the oil pressure is low.
The engine can become so hot that it catches re.
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 brie y 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.
3-49
DIC Warnings and Messages
Messages are displayed on the DIC to notify the driver
that the status of the vehicle has changed and that
some action may be needed by the driver to correct the
condition. Multiple messages may appear one after
another.
Some messages may not require immediate action, but
you can press any of the DIC buttons on the instrument
panel or the trip odometer reset stem on the instrument
panel cluster to acknowledge that you received the
messages and to clear them from the display.
Some messages cannot be cleared from the DIC
display because they are more urgent. These messages
require action before they can be cleared. You should
take any messages that appear on the display seriously
and remember that clearing the messages will only
make the messages disappear, not correct the problem.
The following are the possible messages that can be
displayed and some information about them.
If your vehicle has the DURAMAX
®Diesel engine, see
the DURAMAX Diesel manual for more information.
CHANGE ENGINE OIL SOON
This message displays when the engine oil needs to be
changed. When you change the engine oil, be sure to
reset the CHANGE ENGINE OIL SOON message. See
Engine Oil Life System on page 5-20for information on
how to reset the message. SeeEngine Oil on page 5-17
andScheduled Maintenance (Gasoline Engine) on
page 6-4for more information.
CHECK TIRE PRESSURE
If your vehicle has the Tire Pressure Monitor System
(TPMS), this message displays when the pressure in one
or more of the vehicle’s tires needs to be checked. This
message also displays LEFT FRONT, RIGHT FRONT,
LEFT REAR, or RIGHT REAR to indicate which tire
needs to be checked. You can receive more than one tire
pressure message at a time. To read the other messages
that may have been sent at the same time, press the
set/reset button or the trip odometer reset stem. If a tire
pressure message appears on the DIC, stop as soon as
you can. Have the tire pressures checked and set to
those shown on the Tire Loading Information label. See
Tires on page 5-67,Loading the Vehicle on page 4-34,
andInflation - Tire Pressure on page 5-76. The DIC also
shows the tire pressure values. See “DIC Operation and
Displays (With DIC Buttons)” earlier in this section. If the
tire pressure is low, the low tire pressure warning light
comes on. SeeTire Pressure Light on page 3-45.
3-66
SERVICE BRAKES SOON
This message displays if there is a problem with the
brake system. If this message appears, stop as soon as
possible and turn off the vehicle. Restart the vehicle and
check for the message on the DIC display. If the message
is still displayed or appears again when you begin driving,
the brake system needs service. See your dealer/retailer.
SERVICE PARK ASSIST
If your vehicle has the Ultrasonic Rear Parking Assist
(URPA) system, this message displays if there is a
problem with the URPA system. Do not use this system
to help you park. SeeUltrasonic Rear Parking Assist
(URPA) on page 2-61for more information. See your
dealer/retailer for service.
SERVICE STABILITRAK
If your vehicle has StabiliTrak®and this message
displays, it means there may be a problem with the
StabiliTrak system. If you see this message, try to
reset the system. Stop; turn off the engine for at least
15 seconds; then start the engine again. If this message
still comes on, it means there is a problem. You should
see your dealer/retailer for service. The vehicle is safe to
drive, however, you do not have the bene t of StabiliTrak,
so reduce your speed and drive accordingly.
SERVICE THEFT DETERRENT SYSTEM
This message displays when there is a problem with the
theft-deterrent system. The vehicle may or may not
restart so you may want to take the vehicle to your
dealer/retailer before turning off the engine. See
PASS-Key
®III+ Electronic Immobilizer Operation on
page 2-20for more information.
SERVICE TIRE MONITOR SYSTEM
If your vehicle has the Tire Pressure Monitor System
(TPMS), this message displays if a part on the system is
not working properly. The tire pressure light also ashes
and then remains on during the same ignition cycle. See
Tire Pressure Light on page 3-45. Several conditions may
cause this message to appear. SeeTire Pressure Monitor
Operation on page 5-80for more information. If the
warning comes on and stays on, there may be a problem
with the TPMS. See your dealer/retailer.
SERVICE TRACTION CONTROL
If your vehicle has StabiliTrak, this message displays
when there is a problem with the Traction Control System
(TCS). When this message displays, the system will not
limit wheel spin. Adjust your driving accordingly. See your
dealer/retailer for service. SeeStabiliTrak
®System on
page 4-6for more information.
3-72
SERVICE TRAILER BRAKE SYSTEM
On vehicles with the Integrated Trailer Brake Control
(ITBC) system, this message displays and a chime
sounds when there is a problem with the ITBC system.
When this message displays, power is no longer
available to the trailer brakes.
As soon as it is safe to do so, carefully pull your vehicle
over to the side of the road and turn the ignition off.
Check the wiring connection to the trailer and turn the
ignition back on. If this message still displays, either
your vehicle or the trailer needs service. See your
dealer/retailer.
See “Integrated Trailer Brake Control System” under
Towing a Trailer on page 4-53for 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 bene ts 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 drivingin extreme off-road conditions and require more wheel
spin. SeeIf Your Vehicle is Stuck in Sand, Mud, Ice, or
Snow on page 4-32. To turn the StabiliTrak system on or
off, seeStabiliTrak
®System on page 4-6.
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 3-42.
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 also displays if the vehicle is shifted
into 4LO.
The message turns off as soon as the conditions that
caused the message to be displayed are no longer
present.
3-73
TIGHTEN GAS CAP
This message may display 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 3-45. Reinstall the fuel cap fully. See
Filling the Tank on page 5-11. 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. See “DIC
Operation and Displays (Without DIC Buttons)” earlier in
this section for more information. The tire positions must
be re-learned after rotating the tires or after replacing a
tire or sensor. SeeTire Inspection and Rotation on
page 5-84,Tire Pressure Monitor System on page 5-79,
andInflation - Tire Pressure on page 5-76for 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 4-6for more information.
TRAILER CONNECTED
On vehicles with the Integrated Trailer Brake Control
(ITBC) system, this message displays brie y when a
trailer with electric brakes is rst connected to the vehicle.
This message clears itself after several seconds. This
message also clears if you acknowledge it. After this
message clears, the TRAILER GAIN/OUTPUT display
appears in the DIC.
See “TRAILER GAIN/OUTPUT” underDIC Operation and
Displays (With DIC Buttons) on page 3-53orDIC
Operation and Displays (Without DIC Buttons) on
page 3-59and “Integrated Trailer Brake Control System”
underTowing a Trailer on page 4-53for more
information.
3-74
Antilock Brake System (ABS)
This vehicle has the Antilock Brake System (ABS), an
advanced electronic braking system that helps prevent a
braking skid.
When the engine is started and the vehicle begins to
drive away, ABS checks itself. A momentary motor
or clicking noise might be heard while this test is going
on. This is normal.
If there is a problem with
ABS, this warning light
stays on. SeeAntilock
Brake System (ABS)
Warning Light on
page 3-43.
Along with ABS, the vehicle has a Dynamic Rear
Proportioning (DRP) system. If there is a DRP problem,
both the brake and ABS warning lights come on
accompanied by a 10-second chime. The lights and
chime will come on each time the ignition is turned on
until the problem is repaired. See your dealer/retailer for
service.Let us say the road is wet and you are driving safely.
Suddenly, an animal jumps out in front of you. You slam
on the brakes and continue braking. Here is what
happens with ABS:
A computer senses that the wheels are slowing down.
If one of the wheels is about to stop rolling, the computer
will separately work the brakes at each front wheel
and at both rear wheels.
ABS can change the brake pressure to each wheel, as
required, faster than any driver could. This can help
the driver steer around the obstacle while braking hard.
As the brakes are applied, the computer keeps
receiving updates on wheel speed and controls braking
pressure accordingly.
Remember: ABS does not change the time needed to get
a foot up to the brake pedal or always decrease stopping
distance. If you get too close to the vehicle in front of you,
there will not be enough time to apply the brakes if that
vehicle suddenly slows or stops. Always leave enough
room up ahead to stop, even with ABS.
Using ABS
Do not pump the brakes. Just hold the brake pedal
down rmly and let antilock work. The brakes might
vibrate or some noise might be heard, but this is normal.
4-5
{CAUTION:
Snow can trap engine exhaust under the vehicle.
This may cause exhaust gases to get inside.
Engine exhaust contains carbon monoxide (CO)
which cannot be seen or smelled. It can cause
unconsciousness and even death.
If the vehicle is stuck in the snow:
Clear away snow from around the base of
your vehicle, especially any that is blocking
the exhaust pipe.
Check again from time to time to be sure
snow does not collect there.
Open a window about two inches (5 cm) on
the side of the vehicle that is away from the
wind to bring in fresh air.
Fully open the air outlets on or under the
instrument panel.
Adjust the Climate Control system to a setting
that circulates the air inside the vehicle and
set the fan speed to the highest setting.
See Climate Control System in the Index.
CAUTION: (Continued)
CAUTION: (Continued)
For more information about carbon monoxide,
seeEngine Exhaust on page 2-55.
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 cannot 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 the exhaust.
Run the engine for short periods only as needed to keep
warm, but be careful.
To save fuel, run the engine for only short periods as
needed to warm the vehicle and then shut the engine off
and close the window most of the way to save heat.
Repeat this until help arrives but only when you feel really
uncomfortable from the cold. Moving about to keep warm
also helps.
If it takes some time for help to arrive, now and then
when you run the engine, push the accelerator pedal
slightly so the engine runs faster than the idle speed. This
keeps the battery charged to restart the vehicle and to
signal for help with the headlamps. Do this as little as
possible to save fuel.
4-31