2005 CHEVROLET BLAZER light

Tow/Haul Mode
Your vehicle may be equipped with a tow/haul feature.
Tow/haul is designed to assist while your vehicle is
pulling a large or heavy load or trailer. Tow/haul is most
useful while pulling such a load in rolling terrain at
speeds less than 55 mph (88 km/h), in stop-and-go
traffic, or when you need improved low-speed control,
such as when parking. The purpose of the tow/haul
mode is to do the following:
Reduce the frequency and improve the predictability
or transmission shifts
provide the same solid shift feel while pulling a
heavy load as while the vehicle is unloaded, and
improve control of vehicle speed while requiring less
throttle pedal activity
Press the button on the end of the shift lever to turn
tow/haul mode on and off. While activated, the indicator
light on the instrument panel will be on. Tow/haul
mode will turn off automatically when the ignition is
turned off. SeeTow/Haul Mode Light on page 3-34.
Tow/haul mode is most effective when the vehicle and
load combined weight is at least 75 percent of the
vehicle’s Gross Vehicle Weight Rating (GVWR) and the
maximum trailer weight rating for the vehicle. See
“Weight of the Trailer” later in this section.Driving with tow/haul activated without a heavy load will
cause reduced fuel economy and unpleasant engine
and transmission driving characteristics, but will
not cause damage.
Weight of the Trailer
How heavy can a trailer safely be?
It depends on how you plan to use your rig. For
example, speed, altitude, road grades, outside
temperature and how much your vehicle is used to pull
a trailer are all important. And, it can also depend
on any special equipment that you have on your vehicle.
The following chart shows how much your trailer can
weigh, based upon your vehicle model and options.
Maximum trailer weight is calculated assuming the driver
and one passenger are in the tow vehicle and it has
all the required trailering equipment. The weight
of additional optional equipment, passengers and cargo
in the tow vehicle must be subtracted from the
maximum trailer weight. The weight of the trailer tongue
also affects the maximum trailer weight. See “ Weight
of the Trailer Tongue ” later in this section.
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Driving On Grades
Reduce speed and shift to a lower gearbeforeyou start
down a long or steep downgrade. If you don’t shift
down, you might have to use your brakes so much that
they would get hot and no longer work well.
If you have an automatic transmission, you can tow in
DRIVE (D). You may want to shift the transmission
to THIRD (3) or, if necessary, a lower gear selection if
the transmission shifts too often (e.g., under heavy loads
and/or hilly conditions). Or, if you have a manual
transmission and you are towing a trailer, it’s better not
to use FIFTH (5) gear. Just drive in FOURTH (4)
gear (or, as you need to, a lower gear). SeeTow/Haul
Mode Light on page 3-34.
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a lower
temperature than at normal altitudes. If you turn your
engine off immediately after towing at high altitude
on steep uphill grades, your vehicle may show signs
similar to engine overheating. To avoid this, let the
engine run while parked (preferably on level ground)
with the automatic transmission in PARK (P) (or
the manual transmission out of gear and the parking
brake applied) for a few minutes before turning the
engine off. If you do get the overheat warning,
seeEngine Overheating on page 5-28.
Parking on Hills
{CAUTION:
You really should not park your vehicle, with a
trailer attached, on a hill. If something goes
wrong, your rig could start to move. People
can be injured, and both your vehicle and the
trailer can be damaged.
But if you ever have to park your rig on a hill, here’s
how to do it:
1. Apply your regular brakes, but don’t shift into
PARK (P) yet, or into gear for a manual
transmission. Then turn your wheels into the curb if
facing downhill or into traffic if facing uphill.
2. Have someone place chocks under the trailer
wheels.
3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb the load.
4. Reapply the regular brakes. Then apply your
parking brake, and then shift into PARK (P), or
REVERSE (R) for a manual transmission.
4-68

Maintenance When Trailer Towing
Your vehicle will need service more often when you’re
pulling a trailer. See the Maintenance Schedule for more
on this. Things that are especially important in trailer
operation are automatic transmission uid (don’t overll),
engine oil, axle lubricant, belt, cooling system and
brake system. Each of these is covered in this manual,
and the Index will help you nd them quickly. If
you’re trailering, it’s a good idea to review these sections
before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Trailer Wiring Harness
The light-duty trailer wiring is a six-wire harness
assembly. The optional heavy-duty trailer wiring is an
eight-wire harness assembly. The harnesses are stored
under the vehicle, along the passenger-side frame
crossmember on two-door vehicles or on the driver’s
side corner frame rear crossmember on four-door
vehicles. The heavy-duty trailer wiring is fused in the
engine compartment fuse block. SeeFuses and Circuit
Breakers on page 5-97. Both harnesses have no
connector and should be wired by a qualied electrical
technician. The technician can use the following
color code chart when connecting the wiring harness to
your trailer.
Dark Blue: Use for electric trailer brakes or auxiliary
wiring (eight-wire harness only).
Red: Use for battery charging; it connects to the
starter solenoid (eight-wire harness only).
Light Green: Back-up lamps.
Brown: Taillamps and parking lamps.
Yellow: Driver’s side stoplamp and turn signal.
Dark Green: Passenger’s side stoplamp and turn
signal.
White: Ground wire.
Light Blue: Auxiliary stoplamp.
Securely attach the harness to the trailer, then tape or
strap it to your vehicle’s frame rail. Be sure you
leave it loose enough so the wiring doesn’t bend or
break, but not so loose that it drags on the ground. Store
the harness in its original place. Wrap the harness
together and tie it neatly so it won’t be damaged.
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{CAUTION:
If you spill fuel and then something ignites it,
you could be badly burned. Fuel can spray out
on you if you open the fuel cap too quickly.
This spray can happen if your tank is nearly
full, and is more likely in hot weather. Open
the fuel cap slowly and wait for any hiss noise
to stop. Then unscrew the cap all the way.
Be careful not to spill fuel. Do not top off or overll the
tank and wait a few seconds after you have nished
pumping before removing the nozzle. Clean fuel
from painted surfaces as soon as possible. See
Washing Your Vehicle on page 5-90.
When replacing the fuel cap, turn it to the right
(clockwise) until it clicks. Make sure the cap is fully
installed. The diagnostic system can determine if the fuel
cap has been left off or improperly installed. This
would allow fuel to evaporate into the atmosphere. See
Malfunction Indicator Lamp on page 3-30.
{CAUTION:
If a re starts while you are refueling, do not
remove the nozzle. Shut off the ow of fuel by
shutting off the pump or by notifying the
station attendant. Leave the area immediately.
Notice:If you need a new fuel cap, be sure to get
the right type. Your dealer can get one for you.
If you get the wrong type, it may not t properly.
This may cause your malfunction indicator lamp to
light and may damage your fuel tank and emissions
system. SeeMalfunction Indicator Lamp on
page 3-30.
5-9

Engine Air Cleaner/Filter
SeeEngine Compartment Overview on page 5-12for
more information on the location of the engine air
cleaner/lter.
When to Inspect the Engine Air
Cleaner/Filter
Inspect the air cleaner/lter every 15,000 miles
(25 000 km) and replace every 45,000 miles
(75 000 km). If you are driving in dusty/dirty conditions,
inspect the lter at each engine oil change.
How to Inspect the Engine Air
Cleaner/Filter
To inspect the air cleaner/lter remove the lter from the
vehicle and lightly shake the lter to release loose
dust and dirt. If the lter remains caked with dirt, a new
lter is required.
To inspect or replace the lter do the following:
1. Remove the fasteners that hold the cover on and
remove the cover.
2. Inspect or replace the engine air clear/lter. See
Normal Maintenance Replacement Parts on
page 6-34to determine which lter to use.
3. Reinstall the air cleaner/lter cover and fasteners.
5-18

How to Check and Add Fluid
The proper uid should be added if the level does not
reach the bottom of the diaphragm when it is in place in
the reservoir. See the instructions on the reservoir cap.
Engine Coolant
The cooling system in your vehicle is lled with
DEX-COOL®engine coolant. This coolant is designed
to remain in your vehicle for ve years or 150,000 miles
(240 000 km), whichever occurs rst, if you add only
DEX-COOL
®extended 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, seeEngine Overheating on
page 5-28.A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
Give freezing protection down to−34°F (−37°C).
Give boiling protection up to 265°F (129°C).
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-COOL
®may
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
®(silicate-free) coolant in your vehicle.
5-25

Brake Wear
If you have four-wheel drive, your vehicle has four-wheel
disc brakes. If not, your vehicle has front disc brakes
and rear drum brakes.
Disc brake pads have built-in wear indicators that make
a high-pitched warning sound when the brake pads
are worn and new pads are needed. The sound
may come and go or be heard all the time your vehicle
is moving, except when you are pushing on the
brake pedal rmly.
{CAUTION:
The brake wear warning sound means that
soon your brakes will not work well. That
could lead to an accident. When you hear the
brake wear warning sound, have your vehicle
serviced.
Notice:Continuing to drive with worn-out brake
pads could result in costly brake repair.
Some driving conditions or climates may cause a brake
squeal when the brakes are rst applied or lightly
applied. This does not mean something is wrong with
your brakes.Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts in
the proper sequence to GM torque specications.
If you have rear drum brakes, they do not have wear
indicators, but if you ever hear a rear brake rubbing
noise, have the rear brake linings inspected immediately.
Also, the rear brake drums should be removed and
inspected each time the tires are removed for rotation or
changing. When you have the front brake pads
replaced, have the rear brakes inspected, too.
Brake linings should always be replaced as complete
axle sets.
SeeBrake System Inspection on page 6-31.Brake Pedal Travel
See your dealer if the brake pedal does not return to
normal height, or if there is a rapid increase in
pedal travel. This could be a sign of brake trouble.
Brake Adjustment
Every time you make a brake stop, your disc brakes
adjust for wear.
If you do not have four-wheel drive and your brake
pedal goes down farther than normal, your rear drum
brakes may need adjustment. Adjust them by backing up
and rmly applying the brakes a few times.
5-40

Jump Starting
If your battery has run down, you may want to use
another vehicle and some jumper cables to start your
vehicle. Be sure to use the following steps to do it safely.
{CAUTION:
Batteries can hurt you. They can be dangerous
because:
They contain acid that can burn you.
They contain gas that can explode or
ignite.
They contain enough electricity to
burn you.
If you do not follow these steps exactly, some
or all of these things can hurt you.
Notice:Ignoring these steps could result in costly
damage to your vehicle that would not be covered
by your warranty.
Trying to start your vehicle by pushing or pulling it
will not work, and it could damage your vehicle.
1. Check the other vehicle. It must have a 12-volt
battery with a negative ground system.Notice:If the other vehicle’s system is not a 12-volt
system with a negative ground, both vehicles can
be damaged. Only use vehicles with 12-volt systems
with negative grounds to jump start your vehicle.
2. Get the vehicles close enough so the jumper cables
can reach, but be sure the vehicles are not touching
each other. If they are, it could cause a ground
connection you do not want. You would not be able
to start your vehicle, and the bad grounding
could damage the electrical systems.
To avoid the possibility of the vehicles rolling, set
the parking brake rmly on both vehicles involved in
the jump start procedure. Put an automatic
transmission in PARK (P) or a manual transmission
in NEUTRAL before setting the parking brake. If
you have a four-wheel-drive vehicle, be sure
the transfer case is not in NEUTRAL (N).
Notice:If you leave your radio or other accessories
on during the jump starting procedure, they could
be damaged. The repairs would not be covered
by your warranty. Always turn off your radio and
other accessories when jump starting your vehicle.
3. Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter or the accessory power outlets. Turn off
the radio and all lamps that are not needed. This
will avoid sparks and help save both batteries. And
it could save the radio!
5-42