2003 CHEVROLET TRAIL BLAZER check engine light

Service Four-Wheel Drive Warning
Light
This light should come on brie¯y when you turn on the
ignition, as a check to show you it is working.
The SERVICE 4WD light comes on to indicate that
there may be a problem with the drive system and
service is required. Malfunctions can be indicated by the
system before any problem is apparent, which may
prevent serious damage to the vehicle. This system is
also designed to assist your service technician in
correctly diagnosing a malfunction.
Check Gages Warning Light
The CHECK GAGES light will come on brie¯y when you
are starting the engine.
If the light comes on and stays on while you are driving,
check your coolant temperature and engine oil
pressure gages to see if they are in the warning zones. United StatesCanada
United StatesCanada
3-49

Anti-lock Brake System
Your vehicle has anti-lock brakes. ABS is an advanced
electronic braking system that will help prevent a
braking skid.
When you start your engine and begin to drive away,
your anti-lock brake system will check itself. You
may hear a momentary motor or clicking noise while
this test is going on. This is normal.
If there is a problem with
the anti-lock brake system,
this warning light will
stay on. See
Anti-Lock
Brake System Warning
Light on page 3-42
.
Along with ABS, your vehicle has a Dynamic Rear
Proportioning (DRP) system. If there is a DRP problem,
both the brake and ABS warning lights will 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 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 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.
4-7

{CAUTION:
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 can not 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 your exhaust pipe. And check around
again from time to time to be sure snow does
not collect there.
Open a window just a little on the side of the
vehicle that is away from the wind. This will
help keep CO out.Run your engine only as long as you must. This saves
fuel. When you run the engine, make it go a little
faster than just idle. That is, push the accelerator
slightly. This uses less fuel for the heat that you get and
it keeps the battery charged. You will need a
well-charged battery to restart the vehicle, and possibly
for signaling later on with your headlamps. Let the
heater run for a while.
Then, shut the engine off and close the window almost
all the way to preserve the heat. Start the engine
again and repeat this only when you feel really
uncomfortable from the cold. But do it as little as
possible. Preserve the fuel as long as you can. To help
keep warm, you can get out of the vehicle and do
some fairly vigorous exercises every half hour or so until
help comes.
4-41

As in the chart shown previously, SAE 5W-30 is the
only viscosity grade recommended for your vehicle. You
should look for and use only oils which have the API
Starburst symbol and which are also identi®ed as
SAE 5W-30. If you cannot ®nd such SAE 5W-30 oils,
you can use an SAE 10W-30 oil which has the API
Starburst symbol, if it's going to be 0ÉF (-18ÉC)
or above. Do not use other viscosity grade oils, such as
SAE 10W-40 or SAE 20W-50 under any conditions.
Notice:Use only engine oil with the American
Petroleum Institute Certi®ed For Gasoline Engines
starburst symbol. Failure to use the recommended
oil can result in engine damage not covered by
your warranty.
GM Goodwrench
žoil meets all the requirements for
your vehicle.
If you are in an area of extreme cold, where the
temperature falls below-20ÉF (-29ÉC), it is
recommended that you use either an
SAE 5W-30 synthetic oil or an SAE 0W-30 oil.
Both will provide easier cold starting and better
protection for your engine at extremely low
temperatures.
Engine Oil Additives
Don't add anything to your oil. The recommended oils
with the starburst symbol are all you will need for
good performance and engine protection.
When to Change Engine Oil
(GM Oil Life System)
Your vehicle has a computer system that lets you know
when to change the engine oil and ®lter. This is
based on engine revolutions and engine temperature,
and not on mileage. Based on driving conditions,
the mileage at which an oil change will be indicated can
vary considerably. For the oil life system to work
properly, you must reset the system every time the oil is
changed.
When the system has calculated that oil life has been
diminished, it will indicate that an oil change is
necessary. A CHANGE ENG OIL light will come on.
Change your oil as soon as possible within the
next two times you stop for fuel. It is possible that, if
you are driving under the best conditions, the oil
life system may not indicate that an oil change is
necessary for over a year. However, your engine oil and
®lter must be changed at least once a year and at
this time the system must be reset. It is also important
to check your oil regularly and keep it at the proper
level.
If the system is ever reset accidentally, you must
change your oil at 3,000 miles (5 000 km) since your
last oil change. Remember to reset the oil life system
whenever the oil is changed.
5-19

How to Add Fluid
Refer to the Maintenance Schedule to determine
what kind of transmission ¯uid to use. See
Part D: Recommended Fluids and Lubricants on
page 6-18.
Add ¯uid only after checking the transmission ¯uid while
it is hot. (A cold check is used only as a reference.) If
the ¯uid level is low, add only enough of the proper
¯uid to bring the level up to the HOT area for a
hot check. It doesn't take much ¯uid, generally less
than one pint (0.5 L).
Don't over®ll.
Notice:
We recommend you use only ¯uid labeled
DEXRONž-III, because ¯uid with that label is
made especially for your automatic transmission.
Damage caused by ¯uid other than DEXRON
ž-III is
not covered by your new vehicle warranty.
·After adding ¯uid, recheck the ¯uid level as
described under ªHow to Check².
·When the correct ¯uid level is obtained, push the
dipstick back in all the way; then ¯ip the handle
down to lock the dipstick in place.
Engine Coolant
The cooling system in your vehicle is ®lled with
DEX-COOLžengine coolant. This coolant is designed
to remain in your vehicle for 5 years or 150,000 miles
(240 000 km), whichever occurs ®rst, if you add
only DEX-COOL
žextended life coolant.
The following explains your cooling system and how to
add coolant when it is low. If you have a problem
with engine overheating, see
Engine Overheating on
page 5-27.
A 50/50 mixture of clean, drinkable water and
DEX-COOL
žcoolant will:
·Give freezing protection down to-34ÉF (-37ÉC).
·Give boiling protection up to 265ÉF (129ÉC).
·Protect against rust and corrosion.
·Help keep the proper engine temperature.
·Let the warning lights and gages work as they
should.
Notice:Using coolant other than DEX-COOLžmay
cause premature engine, heater core or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs ®rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
ž(silicate-free) coolant in your vehicle.
5-24

Scheduled Maintenance
The services shown in this schedule up to 100,000 miles
(166 000 km) should be repeated after 100,000 miles
(166 000 km) at the same intervals for the life of
this vehicle. The services shown at 150,000 miles
(240 000 km) should be repeated at the same interval
after 150,000 miles (240 000 km) for the life of this
vehicle.
See
Part B: Owner Checks and Services on page 6-11andPart C: Periodic MaintenanceInspections on
page 6-16.
Footnotes
²The U.S. Environmental Protection Agency or the
California Air Resources Board has determined that the
failure to perform this maintenance item will not nullify
the emission warranty or limit recall liability prior to
the completion of the vehicle's useful life. We, however,
urge that all recommended maintenance services be
performed at the indicated intervals and the
maintenance be recorded.
+A good time to check your brakes is during tire
rotation. See Brake System Inspection on page 6-17.
Engine Oil Scheduled Maintenance
Change engine oil and ®lter as indicated by the GM
Oil Life System (or every 12 months, whichever
occurs ®rst). Reset the system.
Your vehicle has a computer system that lets you know
when to change the engine oil and ®lter. This is
based on engine revolutions and engine temperature,
and not on mileage. Based on driving conditions,
the mileage at which an oil change will be indicated can
vary considerably. For the oil life system to work
properly, you must reset the system every time the oil is
changed.
When the system has calculated that oil life has been
diminished, it will indicate that an oil change is
necessary. A CHANGE ENGINE OIL light will come on.
Change your oil as soon as possible within the next
two times you stop for fuel. It is possible that, if you are
driving under the best conditions, the oil life system
may not indicate that an oil change is necessary for over
a year. However, your engine oil and ®lter must be
changed at least once a year and at this time the system
must be reset. Your dealer has GM-trained service
people who will perform this work using genuine GM
parts and reset the system.
6-5

A
Accessory Power Outlets.................................3-20
Adding a Snow Plow or Similar Equipment.........4-50
Adding Washer Fluid.......................................5-37
Additional Program Information........................... 7-8
Additives, Fuel................................................. 5-6
Add-On Electrical Equipment............................5-88
Adjusting the Speakers
(Balance/Fade)............................3-67, 3-75, 3-84
After Off-Road Driving.....................................4-28
Air Bag Systems.............................................1-49
How Does an Air Bag Restrain?....................1-56
Servicing Your Air Bag-Equipped Vehicle.........1-59
What Makes an Air Bag In¯ate?....................1-56
What Will You See After an Air
Bag In¯ates?...........................................1-57
When Should an Air Bag In¯ate?...................1-55
Where Are the Air Bags?..............................1-52
Air Bag .........................................................3-38
Readiness Light..........................................3-38
Air Cleaner/Filter, Engine.................................5-20
AM .............................................................3-106
Antenna, Fixed Mast......................................3-108
Anti-Lock Brake, System Warning Light..............3-42
Anti-lock Brake System..................................... 4-7
Appearance Care............................................5-79
Care of Safety Belts....................................5-82
Chemical Paint Spotting...............................5-85
Cleaning the Inside of Your Vehicle................5-79Appearance Care (cont.)
Cleaning the Outside of Your Vehicle..............5-82
Finish Damage............................................5-85
Sheet Metal Damage...................................5-84
Underbody Maintenance...............................5-85
Vehicle Care/Appearance Materials................5-86
Weatherstrips..............................................5-82
Approaching a Hill..........................................4-20
Ashtrays........................................................3-20
Audio Speakers..............................................3-94
Audio System(s).............................................3-64
Audio Steering Wheel Controls....................3-106
Care of Your Cassette Tape Player...............3-107
Care of Your CD and DVD Player................3-108
Care of Your CDs and DVDs.......................3-108
Chime Level Adjustment.............................3-108
Fixed Mast Antenna...................................3-108
Audio Systems..............................................3-105
Radio Personalization.................................3-105
Audio System(s).............................................3-72
Radio with Cassette and CD.........................3-72
Radio with CD............................................3-65
Radio with Six-Disc CD................................3-82
Rear Seat Audio (RSA)...............................3-104
Setting the Time..........................................3-64
Theft-Deterrent Feature...............................3-105
Understanding Radio Reception...................3-106
Automatic Headlamp System............................3-16
Automatic Transfer Case..................................2-25
Automatic Transmission Check..........................6-12
1

Automatic Transmission Shift Lock Control
System Check.............................................6-14
Automatic Transmission...................................5-22
Fluid..........................................................5-22
Operation...................................................2-22
B
Backglass Wiper Blade Replacement.................5-53
Backing Up....................................................4-57
BATTERY NOT CHARGING.............................3-61
Battery Replacement......................................... 2-7
Battery Run-Down Protection............................3-19
Battery..........................................................5-41
Before Leaving on a Long Trip.........................4-35
Before You Drive............................................3-93
Before You Go Off-Roading..............................4-16
Body Lubrication Service..................................6-13
Brake Adjustment............................................5-40
Brake Fluid....................................................5-38
Brake Pedal Travel.........................................5-40
Brake Wear...................................................5-40
Brake............................................................2-28
Parking......................................................2-28
System Inspection.......................................6-17
System Warning Light..................................3-41
Brakes..........................................................5-38
Braking in Emergencies..................................... 4-8
Braking........................................................... 4-6Break-In, New Vehicle.....................................2-18
Bulb Replacement...........................................5-50
Replacement Bulbs......................................5-51
Taillamps and Turn Signal Lamps..................5-50
Buying New Tires...........................................5-58
C
California Fuel.................................................. 5-5
Canada ± Customer Assistance.......................... 7-4
Canadian Owners................................................ ii
Canadian Roadside Assistance........................... 7-6
Capacities and Speci®cations..........................5-100
Carbon Monoxide...................4-38, 4-50, 2-13, 2-32
Care of.........................................................5-82
Safety Belts................................................5-82
Your Cassette Tape Player..........................3-107
Your CD and DVD Player...........................3-108
Your CDs and DVDs..................................3-108
Cargo Cover..................................................2-49
Cargo Tie Downs............................................2-50
Cassette Tape Messages.................................3-79
Cassette Tape Player Service...........................6-11
Chains, Tires..................................................5-62
Charging System Light....................................3-39
Check...........................................................3-43
Engine Light...............................................3-43
Gages Warning Light...................................3-49
CHECK WASHER FLUID.................................3-62
2