2009 CHEVROLET TAHOE check engine light

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
The oil pressure gage shows the engine oil pressure in
psi (pounds per square inch) when the engine is
running. Canadian vehicles indicate pressure in
kPa (kilopascals).United States
Canada
3-46

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 briey 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 owing 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
Content Theft-Deterrent on
page 2-22.
3-48

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 is a Two-mode Hybrid, see the Two-mode
Hybrid 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.
SeeEngine Oil Life System on page 5-18for information
on how to reset the message. SeeEngine Oil on
page 5-15andScheduled Maintenance on page 6-4for
more information.
CHECK TIRE PRESSURE
On vehicles with 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. SeeTires on page 5-62,Loading the
Vehicle on page 4-33, andInflation - Tire Pressure
on page 5-70. 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 3-43.
3-64

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 3-40.
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.
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 3-43. Reinstall the fuel cap fully.
SeeFilling the Tank on page 5-9. 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
On vehicles with the Tire Pressure Monitor System
(TPMS), this message displays when the TPMS
is re-learning the tire positions on your vehicle. The tire
positions must be re-learned after rotating the tires
or after replacing a tire or sensor. SeeTire Inspection
and Rotation on page 5-76,Tire Pressure Monitor
System on page 5-71, andInflation - Tire Pressure on
page 5-70for 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.
3-72

Antilock Brake System (ABS)
This vehicle has the Antilock Brake System (ABS), an
advanced electronic braking system that will help
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 3-41.
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

This vehicle has an airbag system. Before attempting
to do your own service work, seeServicing Your
Airbag-Equipped Vehicle on page 1-96.
Keep a record with all parts receipts and list the mileage
and the date of any service work performed. See
Maintenance Record on page 6-17.
Adding Equipment to the Outside of
the Vehicle
Things added to the outside of the vehicle can affect the
airow around it. This can cause wind noise and can
affect fuel economy and windshield washer performance.
Check with your dealer/retailer before adding equipment
to the outside of the vehicle.
Fuel
Use of the recommended fuel is an important part of the
proper maintenance of this vehicle. To help keep the
engine clean and maintain optimum vehicle performance,
we recommend the use of gasoline advertised as TOP
TIER Detergent Gasoline.
The 8th digit of the Vehicle Identication Number (VIN)
shows the code letter or number that identies the
vehicle’s engine. The VIN is at the top left of the
instrument panel. SeeVehicle Identification Number
(VIN) on page 5-113.If the vehicle has the 5.3L V8 engine (VIN Code 0), the
5.3L V8 engine (VIN Code 3), or the 6.2L V8 engine
(VIN Code 2–), you can use either unleaded gasoline or
ethanol fuel containing up to 85% ethanol (E85). See
Fuel E85 (85% Ethanol) on page 5-7. In all other
engines, use only unleaded gasoline. SeeGasoline
Octane on page 5-5.
Gasoline Octane
For all vehicles except those with the 6.2L V8 engine
(VIN Code 2), use regular unleaded gasoline with
a posted octane rating of 87 or higher. If the octane
rating is less than 87, you might notice an audible
knocking noise when you drive, commonly referred to
as spark knock. If this occurs, use a gasoline rated at
87 octane or higher as soon as possible. If you are using
gasoline rated at 87 octane or higher and you hear
heavy knocking, the engine needs service.
If the vehicle has the 6.2L V8 engine (VIN Code 2), use
premium unleaded gasoline with a posted octane rating
of 91 or higher. You can also use regular unleaded
gasoline rated at 87 octane or higher, but the vehicle’s
acceleration could be slightly reduced, and you might
notice a slight audible knocking noise, commonly referred
to as spark knock. If the octane is less than 87, you
might notice a heavy knocking noise when you drive.
5-5

Brakes
Brake Fluid
The brake master cylinder
reservoir is lled with
DOT-3 brake uid. See
Engine Compartment
Overview on page 5-14for
the location of the reservoir.
There are only two reasons why the brake uid level in
the reservoir might go down:
The brake uid level goes down because of normal
brake lining wear. When new linings are installed,
the uid level goes back up.
A uid leak in the brake hydraulic system can also
cause a low uid level. Have the brake hydraulic
system xed, since a leak means that sooner
or later the brakes will not work well.Do not top off the brake uid. Adding uid does not
correct a leak. If uid is added when the linings
are worn, there will be too much uid when new brake
linings are installed. Add or remove brake uid, as
necessary, only when work is done on the brake
hydraulic system.
{CAUTION:
If too much brake uid is added, it can spill on the
engine and burn, if the engine is hot enough. You
or others could be burned, and the vehicle could
be damaged. Add brake uid only when work is
done on the brake hydraulic system. See
“Checking Brake Fluid” in this section.
When the brake uid falls to a low level, the brake
warning light comes on. SeeBrake System Warning
Light on page 3-40.
Refer to the Maintenance Schedule to determine when
to check the brake uid. SeeScheduled Maintenance
on page 6-4.
5-40

Check
Engine Lamp..............................................3-43
Checking Things Under the Hood......................5-12
Chemical Paint Spotting.................................5-112
Child Restraints
Child Restraint Systems...............................1-61
Infants and Young Children...........................1-57
Lower Anchors and Tethers for Children..........1-65
Older Children.............................................1-55
Securing a Child Restraint in a Rear Seat
Position..................................................1-73
Securing a Child Restraint in the Center
Front Seat Position...................................1-77
Securing a Child Restraint in the Right
Front Seat Position...................................1-78
Where to Put the Restraint...........................1-64
Cigarette Lighter.............................................3-21
Cleaning
Aluminum or Chrome-Plated Wheels.............5-111
Exterior Lamps/Lenses................................5-109
Fabric/Carpet............................................5-107
Finish Care...............................................5-110
Instrument Panel, Vinyl, and Other Plastic
Surfaces...............................................5-108
Interior.....................................................5-105
Leather....................................................5-107
Tires........................................................5-112
Underbody Maintenance.............................5-112Cleaning (cont.)
Washing Your Vehicle.................................5-109
Weatherstrips............................................5-108
Windshield, Backglass, and Wiper Blades......5-110
Climate Control System...................................3-22
Dual Automatic............................................3-24
Outlet Adjustment........................................3-30
Rear Air Conditioning and Heating System......3-31
Rear Air Conditioning and Heating System,
Electronic................................................3-32
Clock, Setting.................................................3-83
Collision Damage Repair..................................
7-11
Compass.......................................................3-61
Content Theft-Deterrent....................................2-22
Control of a Vehicle.......................................... 4-3
Coolant
Engine.......................................................5-29
Engine Temperature Gage............................3-42
Surge Tank Pressure Cap.............................5-34
Cooled Seats................................................... 1-7
Cooling System..............................................5-28
Cruise Control................................................3-12
Cruise Control Light........................................3-49
Cupholders....................................................2-78
Customer Assistance Information
Courtesy Transportation................................7-10
Customer Assistance for Text Telephone (TTY)
Users....................................................... 7-6
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