2005 CHEVROLET BLAZER ECU

Rear Towing (Rear Wheels off the Ground)
If your vehicle has an electronic transfer case, you
can dolly tow your vehicle from the rear only if the rear
wheels are on the dolly. Use the following steps to
dolly tow your vehicle:
1. Follow the dolly manufacturer’s instructions to
attach and secure the vehicle being towed to
the dolly and then the loaded dolly to the tow
vehicle.
2. Firmly set the parking brake.
3. Put the automatic or manual transmission in
NEUTRAL (N).4. Release the parking brake only after the vehicle
being towed is rmly attached to the towing
vehicle.
{CAUTION:
Shifting a four-wheel-drive vehicle’s transfer
case into NEUTRAL can cause your vehicle to
roll even if the transmission is in Park (P) for
an automatic transmission, or if your vehicle is
in gear, for a manual transmission. You or
others could be injured. Make sure the parking
brake is rmly set before you shift the transfer
case to NEUTRAL.
Notice:Do not exceed the posted speed limit when
towing your vehicle. If you do, your vehicle could
be badly damaged.
5. Turn the ignition to OFF. To prevent your battery
from draining while towing, remove the RDO BATT
and CLSTR fuses from the instrument panel
fuse block. Be sure to replace the fuse when you
reach your destination. SeeInstrument Panel
Fuse Block on page 5-98.
4-56

Dolly Towing
(Two-Wheel-Drive Vehicles)
Front Towing
(Front Wheels off the Ground)
You can dolly tow your vehicle from the front. Use the
following steps to dolly tow your vehicle:
1. Follow the dolly manufacturer’s instructions to
attach and secure the vehicle being towed to
the dolly and then the loaded dolly to the tow
vehicle.
2. Firmly set the parking brake.3. Put the automatic or manual transmission in
NEUTRAL (N).
4. Release the parking brake only after the vehicle
being towed is rmly attached to the towing
vehicle.
5. Turn the ignition to OFF. To prevent your battery
from draining while towing, remove the RDO BATT
and CLSTR fuses from the instrument panel
fuse block. Be sure to replace the fuse when you
reach your destination. SeeInstrument Panel
Fuse Block on page 5-98.
Notice:Do not exceed the posted speed limit when
towing your vehicle. If you do, your vehicle could
be badly damaged.
Notice:If you tow your vehicle from the front for
more than 50 miles (80 km) on a dolly, you could
damage it. Never dolly tow your vehicle from
the front more than 50 miles (80 km).
4-57

Rear Towing (Rear Wheels off the Ground)
You can dolly tow your vehicle from the rear. Use the
following steps to dolly tow your vehicle:
1. Follow the dolly manufacturer’s instructions to
attach and secure the vehicle being towed to
the dolly and then the loaded dolly to the tow
vehicle.
2. Firmly set the parking brake.
3. Put the automatic or manual transmission in
NEUTRAL (N).4. Release the parking brake only after the vehicle
being towed is rmly attached to the towing
vehicle.
Notice:Do not exceed the posted speed limit when
towing your vehicle. If you do, your vehicle could
be badly damaged.
5. Turn the ignition to OFF. To prevent your battery
from draining while towing, remove the RDO BATT
and CLSTR fuses from the instrument panel
fuse block. Be sure to replace the fuse when you
reach your destination. SeeInstrument Panel
Fuse Block on page 5-98.
4-58

Driving with a Trailer
{CAUTION:
If you have a rear-most window open and you
pull a trailer with your vehicle, carbon
monoxide (CO) could come into your vehicle.
You can not see or smell CO. It can cause
unconsciousness or death. SeeEngine
Exhaust on page 2-40. To maximize your safety
when towing a trailer:
Have your exhaust system inspected for
leaks, and make necessary repairs before
starting on your trip.
Keep the rear-most windows closed.
If exhaust does come into your vehicle
through a window in the rear or another
opening, drive with your front, main
heating or cooling system on and with the
fan on any speed. This will bring fresh,
outside air into your vehicle. Do not use
the climate control setting for maximum air
because it only recirculates the air inside
your vehicle. See Climate Control System
in the Index.Towing a trailer requires a certain amount of experience.
Before setting out for the open road, you’ll want to get
to know your rig. Acquaint yourself with the feel of
handling and braking with the added weight of the trailer.
And always keep in mind that the vehicle you are
driving is now a good deal longer and not nearly as
responsive as your vehicle is by itself.
Before you start, check all trailer hitch, parts and
attachments, safety chains, electrical connector, lamps,
tires and mirror adjustment. If the trailer has electric
brakes, start your vehicle and trailer moving and then
apply the trailer brake controller by hand to be sure
the brakes are working. This lets you check your
electrical connection at the same time.
During your trip, check occasionally to be sure that the
load is secure, and that the lamps and any trailer
brakes are still working.
4-66

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.
4-70

Remote Oil Filter (Four-Wheel Drive)
The access door for the
remote oil lter is in the
steering linkage shield
assembly located under
the radiator support.
Turn the screw to unlock
or lock the door. If you
open the door, make sure
it is securely closed
when you are nished.
What to Do with Used Oil
Used engine oil contains certain elements that may be
unhealthy for your skin and could even cause cancer.
Do not let used oil stay on your skin for very long. Clean
your skin and nails with soap and water, or a good
hand cleaner. Wash or properly dispose of clothing or
rags containing used engine oil. See the manufacturer’s
warnings about the use and disposal of oil products.
Used oil can be a threat to the environment. If you
change your own oil, be sure to drain all the oil from the
lter before disposal. Never dispose of oil by putting it
in the trash, pouring it on the ground, into sewers, or into
streams or bodies of water. Instead, recycle it by
taking it to a place that collects used oil. If you have a
problem properly disposing of your used oil, ask
your dealer, a service station or a local recycling center
for help.
5-17

Radiator Pressure Cap
Notice:If the pressure cap is not tightly installed,
coolant loss and possible engine damage may
occur. Be sure the cap is properly and tightly
secured.
Engine Overheating
You will nd a coolant temperature gage on your
vehicle’s instrument panel. SeeEngine Coolant
Temperature Gage on page 3-29.
If Steam Is Coming From Your Engine
{CAUTION:
Steam from an overheated engine can burn
you badly, even if you just open the hood. Stay
away from the engine if you see or hear steam
coming from it. Just turn it off and get
everyone away from the vehicle until it cools
down. Wait until there is no sign of steam or
coolant before you open the hood.
If you keep driving when your engine is
overheated, the liquids in it can catch re. You
or others could be badly burned. Stop your
engine if it overheats, and get out of the
vehicle until the engine is cool.
Notice:If your engine catches re because you
keep driving with no coolant, your vehicle can
be badly damaged. The costly repairs would not be
covered by your warranty.
5-28

Tire Inspection and Rotation
Tires should be rotated every 5,000 to 8,000 miles
(8 000 to 13 000 km).
Any time you notice unusual wear, rotate your tires as
soon as possible and check wheel alignment. Also
check for damaged tires or wheels. SeeWhen It Is Time
for New Tires on page 5-65andWheel Replacement
on page 5-69for more information.
Make sure the spare tire is stored securely. Push, pull,
and then try to rotate or turn the tire. If it moves,
use the wheel wrench to tighten the cable. See
Changing a Flat Tire on page 5-72.
The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. The rst rotation
is the most important. SeePart A: Scheduled
Maintenance Services on page 6-4, for scheduled
rotation intervals.When rotating your tires, always use one of the correct
rotation patterns shown here.
If your vehicle has a compact spare tire or a spare tire
that does not match your vehicle’s road tires and
wheels, in size and type, do not include the spare in the
tire rotation.
After the tires have been rotated, adjust the front and
rear ination pressures as shown on the Tire and
Loading Information label. For the location of the tire
and loading information label seeLoading Your Vehicle
on page 4-46. Make certain that all wheel nuts are
properly tightened, see “Wheel Nut Torque” under
Capacities and Specications on page 5-102for the
proper wheel nut torque specication.
5-64