2007 CHEVROLET TRAIL BLAZER check engine

Trailer Brakes
If your trailer weighs more than 1,500 lbs (680 kg)
loaded, then it needs its own brakes — and
they must be adequate. Be sure to read and follow
the instructions for the trailer brakes so you’ll be
able to install, adjust and maintain them properly.
Your trailer’s brake system can tap into the
vehicle’s hydraulic brake system only if:
The trailer parts can withstand 3,000 psi
(20 650 kPa) of pressure.
The trailer’s brake system will use less than
0.02 cubic inch (0.3 cc) of uid from your
vehicle’s master cylinder. Otherwise,
both braking systems won’t work well. You
could even lose your brakes.
If everything checks out this far, then make the
brake uid tap at the port on the master cylinder
that sends uid to the rear brakes. But don’t
use copper tubing for this. If you do, it will bend
and nally break off. Use steel brake tubing.
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. See
Engine Exhaust on page 130. 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.
CAUTION: (Continued)
376

Making Turns
Notice:Making very sharp turns while
trailering could cause the trailer to come in
contact with the vehicle. Your vehicle could be
damaged. Avoid making very sharp turns
while trailering.
When you’re turning with a trailer, make wider
turns than normal. Do this so your trailer
won’t strike soft shoulders, curbs, road signs,
trees or other objects. Avoid jerky or sudden
maneuvers. Signal well in advance.
Turn Signals When Towing a Trailer
The arrows on your instrument panel will
ash whenever you signal a turn or lane change.
Properly hooked up, the trailer lamps will also
ash, telling other drivers you’re about to
turn, change lanes or stop.
When towing a trailer, the arrows on your
instrument panel will ash for turns even if the bulbs
on the trailer are burned out. Thus, you may think
drivers behind you are seeing your signal when
they are not. It’s important to check occasionally to
be sure the trailer bulbs are still working.
Driving On Grades
Reduce speed and shift to a lower gearbefore
you 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.
You can tow in DRIVE (D). You may want to shift
the transmission to THIRD (3) or a lower gear,
under heavy loads or hilly conditions.
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) for a few
minutes before turning the engine off. If you do get
the overheat warning, seeEngine Overheating
on page 418.
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When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the
pedal down while you:
start your engine,
shift into a gear, and
release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear
of the chocks.
4. Stop and have someone pick up and
store the chocks.
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(s), 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.
380

Service........................................................ 386
Accessories and Modications................... 386
California Proposition 65 Warning.............. 386
Doing Your Own Service Work.................. 387
Adding Equipment to the Outside of
Your Vehicle.......................................... 387
Fuel............................................................. 388
Gasoline Octane........................................ 388
Gasoline Specications.............................. 389
California Fuel........................................... 389
Additives................................................... 389
Fuels in Foreign Countries........................ 390
Filling the Tank......................................... 391
Filling a Portable Fuel Container............... 393
Checking Things Under the Hood.............. 394
Hood Release........................................... 394
Engine Compartment Overview.................. 396
Engine Oil................................................. 402
Engine Oil Life System.............................. 408
Engine Air Cleaner/Filter............................ 410Automatic Transmission Fluid.................... 411
Engine Coolant.......................................... 414
Radiator Pressure Cap.............................. 418
Engine Overheating................................... 418
Cooling System......................................... 420
Engine Fan Noise..................................... 425
Power Steering Fluid................................. 426
Windshield Washer Fluid........................... 427
Brakes...................................................... 428
Battery...................................................... 431
Jump Starting............................................ 432
All-Wheel Drive........................................... 438
Rear Axle.................................................... 438
Four-Wheel Drive........................................ 440
Front Axle................................................... 440
Bulb Replacement....................................... 442
Halogen Bulbs........................................... 442
Taillamps and Turn Signal Lamps............. 442
License Plate Lamp................................... 444
Replacement Bulbs................................... 444
Section 5 Service and Appearance Care
383

Gasoline Specications
At a minimum, gasoline should meet ASTM
specication D 4814 in the United States or
CAN/CGSB-3.5 in Canada. Some gasolines may
contain an octane-enhancing additive called
methylcyclopentadienyl manganese tricarbonyl
(MMT). General Motors recommends against the
use of gasolines containing MMT. SeeAdditives
on page 389for additional information.
California Fuel
If your vehicle is certied to meet California
Emissions Standards, it is designed to operate on
fuels that meet California specications. See
the underhood emission control label. If this fuel
is not available in states adopting California
emissions standards, your vehicle will operate
satisfactorily on fuels meeting federal
specications, but emission control system
performance may be affected. The malfunction
indicator lamp may turn on and your vehicle may
fail a smog-check test. SeeMalfunction IndicatorLamp on page 212. If this occurs, return to your
authorized GM dealer for diagnosis. If it is
determined that the condition is caused by the
type of fuel used, repairs may not be covered by
your warranty.
Additives
To provide cleaner air, all gasolines in the
United States are now required to contain additives
that will help prevent engine and fuel system
deposits from forming, allowing your emission
control system to work properly. In most cases,
you should not have to add anything to your fuel.
However, some gasolines contain only the
minimum amount of additive required to meet
U.S. Environmental Protection Agency regulations.
To help keep fuel injectors and intake valves
clean, or if your vehicle experiences problems due
to dirty injectors or valves, look for gasoline that
is advertised as TOP TIER Detergent Gasoline.
Also, your dealer has additives that will help
correct and prevent most deposit-related problems.
389

Checking Things Under
the Hood
{CAUTION:
Things that burn can get on hot engine
parts and start a re. These include
liquids like fuel, oil, coolant, brake uid,
windshield washer and other uids, and
plastic or rubber. You or others could be
burned. Be careful not to drop or spill
things that will burn onto a hot engine.
Hood Release
1. To open the hood,
rst pull the handle
with this symbol
on it. It is located
inside the vehicle
under the instrument
panel on the
driver’s side.
394

A. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 410.
B. Engine Coolant Recovery Tank. SeeCooling
System on page 420.
C. Windshield Washer Fluid Reservoir. See
“Adding Washer Fluid” underWindshield
Washer Fluid on page 427.
D. Power Steering Fluid Reservoir. SeePower
Steering Fluid on page 426.
E. Automatic Transmission Fluid Dipstick (Out of
View). See “Checking the Fluid Level” under
Automatic Transmission Fluid on page 411.
F. Engine Oil Dipstick. See “Checking Engine Oil”
underEngine Oil on page 402.G. Radiator Pressure Cap. SeeRadiator Pressure
Cap on page 418.
H. Engine Oil Fill Cap. See “When to Add Engine
Oil” underEngine Oil on page 402.
I. Remote Negative (−) Terminal (Marked GND).
SeeJump Starting on page 432.
J. Brake Master Cylinder Reservoir. See “Brake
Fluid” underBrakes on page 428.
K. Battery. SeeBattery on page 431.
L. Engine Compartment Fuse Block. SeeEngine
Compartment Fuse Block on page 503.
397

A. Engine Coolant Recovery Tank. SeeCooling
System on page 420.
B. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 410.
C. Windshield Washer Fluid Reservoir. See
“Adding Washer Fluid” underWindshield
Washer Fluid on page 427.
D. Engine Oil Dipstick. See “Checking Engine Oil”
underEngine Oil on page 402.
E. Automatic Transmission Fluid Dipstick.
See “Checking the Fluid Level” under
Automatic Transmission Fluid on page 411.
F. Engine Oil Fill Cap. See “When to Add Engine
Oil” underEngine Oil on page 402.G. Radiator Pressure Cap. SeeRadiator Pressure
Cap on page 418.
H. Remote Negative (−) Terminal (Marked GND).
SeeJump Starting on page 432.
I. Power Steering Fluid Reservoir. SeePower
Steering Fluid on page 426.
J. Brake Master Cylinder Reservoir. See “Brake
Fluid” underBrakes on page 428.
K. Engine Compartment Fuse Block. SeeEngine
Compartment Fuse Block on page 503.
L. Battery. SeeBattery on page 431.
399