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.A trailer with electric brakes has
become disconnected (a
CHECK TRAILER WIRING
message will also display on
the DIC).
. There is a fault present in the
wiring to the trailer brakes (a
CHECK TRAILER WIRING
message will also display on
the DIC).
. The ITBC system is not working
due to a fault (a SERVICE
TRAILER BRAKE SYSTEM
message will also display in
the DIC).
Manual Trailer Brake Apply
The Manual Trailer Brake Apply
Lever is used to apply the trailer ’s
electric brakes independent of the
vehicle’s brakes. Sliding the lever to
the left will apply only the trailer
brakes. Use this lever to adjust
Trailer Gain to properly adjust the
power output to the trailer brakes.
The trailer's and the vehicle's brake
lamps will come on when either
vehicle brakes or manual trailer
brakes are applied. Trailer Gain Adjustment Procedure
Trailer Gain should be set for a
specific trailering condition and must
be adjusted any time vehicle
loading, trailer loading, or road
surface conditions change.
{Warning
Trailer brakes that are
over-gained or under-gained may
not stop the vehicle and the trailer
as intended and can result in a
crash. Always follow the
instructions to set the Trailer Gain
for the proper trailer stopping
performance.
To adjust Trailer Gain for each
towing condition: 1. Drive the vehicle with the trailer attached on a level road
surface representative of the
towing condition and free of
traffic at about 32 to 40 km/h
(20 to 25 mph) and fully apply
the Manual Trailer Brake apply
lever. Adjusting Trailer Gain at
speeds lower than 32 to
40 km/h (20 to 25 mph) may
result in an incorrect gain
setting.
2. Adjust the Trailer Gain, using the Trailer Gain adjustment
buttons, to just below the point
of trailer wheel lock-up,
indicated by trailer wheel
squeal or tire smoke when a
trailer wheel locks.
Trailer wheel lock-up may not
occur if towing a heavily loaded
trailer. In this case, adjust the
Trailer Gain to the highest
allowable setting for the towing
condition.
3. Readjust Trailer Gain any time vehicle loading, trailer loading,
or road surface conditions
change or if trailer wheel
lock-up is noticed at any time
while towing.
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Other ITBC-Related DIC Messages
In addition to displaying TRAILER
GAIN and OUTPUT through the
DIC, trailer connection and ITBC
system status are displayed on
the DIC.
TRAILER CONNECTED: This
message will briefly display when a
trailer with electric brakes is first
connected to the vehicle. This
message will automatically turn off
in about 10 seconds. This message
can be acknowledged before it
automatically turns off.
CHECK TRAILER WIRING: This
message will display if:
.The ITBC system first
determines connection to a
trailer with electric brakes and
then the trailer harness becomes
disconnected from the vehicle.
If the disconnect occurs while
the vehicle is stationary, this
message will automatically turn
off in about 30 seconds. This
message will also turn off if it is
acknowledged or if the trailer
harness is reconnected. If the disconnect occurs while
the vehicle is moving, this
message will continue until the
ignition is turned off. This
message will also turn off if it is
acknowledged or if the trailer
harness is reconnected.
. There is an electrical fault in the
wiring to the trailer brakes. This
message will continue as long
as there is an electrical fault in
the trailer wiring. This message
will also turn off if it is
acknowledged.
To determine if the electrical fault is
on the vehicle side or trailer side of
the trailer wiring harness
connection: 1. Disconnect the trailer wiring harness from the vehicle.
2. Turn the ignition off.
3. Wait 10 seconds, then turn the ignition back to RUN.
4. If the CHECK TRAILER WIRING message reappears,
the electrical fault is on the
vehicle side. If the CHECK TRAILER
WIRING message only
reappears when connecting the
trailer wiring harness to the
vehicle, the electrical fault is on
the trailer side.
SERVICE TRAILER BRAKE
SYSTEM: This message will display
when there is a problem with the
ITBC system. If this message
continues over multiple ignition
cycles, there is a problem with the
ITBC system. Have the vehicle
serviced.
If either the CHECK TRAILER
WIRING or SERVICE TRAILER
BRAKE SYSTEM message displays
while driving, the ITBC system may
not be fully functional or may not
function at all. When traffic
conditions allow, carefully pull the
vehicle over to the side of the road
and turn the ignition off. Check the
wiring connection to the trailer and
turn the ignition back on. If either of
these messages continues, either
the vehicle or trailer needs service.
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282 Driving and Operating
A GM dealer may be able to
diagnose and repair problems with
the trailer. However, any diagnosis
and repair of the trailer is not
covered under the vehicle warranty.
Contact your trailer dealer for
assistance with trailer repairs and
trailer warranty information.
Trailer Sway
Control (TSC)
Vehicles with StabiliTrak have a
Trailer Sway Control (TSC) feature.
Trailer sway is unintended
side-to-side motion of a trailer while
being towed. If the vehicle is towing
a trailer and the TSC detects that
sway is increasing, the vehicle
brakes are selectively applied at
each wheel, to help reduce
excessive trailer sway. If the vehicle
is equipped with the Integrated
Trailer Brake Control (ITBC) system,
and the trailer has the electric
actuated brake system, StabiliTrak
may also apply the trailer brakes.
If TSC is enabled, the Traction
Control System (TCS)/StabiliTrak
warning light will flash on theinstrument cluster. Vehicle speed
must be reduced. If trailer sway
continues, StabiliTrak can reduce
engine torque to help slow the
vehicle. See
Traction Control/
Electronic Stability Control 0241.
{Warning
Even if the vehicle is equipped
with TSC, trailer sway could result
in loss of control and the vehicle
could crash. If excessive trailer
sway is detected, slow down to a
safe speed. Check the trailer and
vehicle to help correct possible
causes. These could include an
improperly or overloaded trailer,
unrestrained cargo, improper
trailer hitch configuration,
excessive vehicle-trailer speed,
or improperly inflated or incorrect
vehicle or trailer tires. See Towing
Equipment 0275 for trailer ratings
and hitch setup
recommendations. Adding non-dealer accessories can
affect the vehicle performance. See
Accessories and Modifications
0
286.
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Conversions and
Add-Ons
Add-On Electrical
Equipment
{Warning
The Data Link Connector (DLC) is
used for vehicle service and
Emission Inspection/
Maintenance testing. See
Malfunction Indicator Lamp
(Check Engine Light)0145.
A device connected to the DLC —
such as an aftermarket fleet or
driver-behavior tracking device —
may interfere with vehicle
systems. This could affect vehicle
operation and cause a crash.
Such devices may also access
information stored in the vehicle’s
systems.
Caution
Some electrical equipment can
damage the vehicle or cause
components to not work and
would not be covered by the
vehicle warranty. Always check
with your dealer before adding
electrical equipment.
Add-on equipment can drain the
vehicle's 12-volt battery, even if the
vehicle is not operating.
The vehicle has an airbag system.
Before attempting to add anything
electrical to the vehicle, see
Servicing the Airbag-Equipped
Vehicle 097 and Adding Equipment
to the Airbag-Equipped Vehicle
0 98.
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284 Vehicle Care
Vehicle Care
General Information
General Information . . . . . . . . . . 285
California Proposition65 Warning . . . . . . . . . . . . . . . . . 285
California Perchlorate Materials Requirements . . . . . 285
Accessories and Modifications . . . . . . . . . . . . . . . . 286
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 286
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 287
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 288
Engine Oil . . . . . . . . . . . . . . . . . . . . 291
Engine Oil Life System . . . . . . . 293
Automatic Transmission Fluid (6-Speed Transmission) . . . . . 294
Automatic Transmission Fluid (8-Speed Transmission) . . . . . 297
Engine Air Cleaner/Filter . . . . . . 298
Cooling System . . . . . . . . . . . . . . 299
Engine Coolant . . . . . . . . . . . . . . . 300
Engine Overheating . . . . . . . . . . 302
Engine Fan . . . . . . . . . . . . . . . . . . . 304
Washer Fluid . . . . . . . . . . . . . . . . . 304
Brakes . . . . . . . . . . . . . . . . . . . . . . . 305 Brake Fluid . . . . . . . . . . . . . . . . . . . 306
Battery - North America . . . . . . 307
Four-Wheel Drive . . . . . . . . . . . . . 307
Front Axle . . . . . . . . . . . . . . . . . . . . 308
Rear Axle . . . . . . . . . . . . . . . . . . . . 309
Noise Control System . . . . . . . . 309
Starter Switch Check . . . . . . . . . 310
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 311
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . . . 311
Park Brake and P (Park) Mechanism Check . . . . . . . . . . 311
Wiper Blade Replacement . . . . 312
Glass Replacement . . . . . . . . . . 313
Windshield Replacement . . . . . 313
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . . . 313
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 314
High Intensity Discharge (HID) Lighting . . . . . . . . . . . . . . . . . . . . . 314
LED Lighting . . . . . . . . . . . . . . . . . 314
Fog Lamps . . . . . . . . . . . . . . . . . . . 314
Back-Up Lamps . . . . . . . . . . . . . . 314
License Plate Lamp . . . . . . . . . . 315
Replacement Bulbs . . . . . . . . . . . 316
Electrical System
Electrical System Overload . . . 316
Fuses . . . . . . . . . . . . . . . . . . . . . . . . 317
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 317
Instrument Panel Fuse
Block (Left) . . . . . . . . . . . . . . . . . 321
Instrument Panel Fuse Block (Right) . . . . . . . . . . . . . . . . . . . . . . 324
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 326
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 327
All-Season Tires . . . . . . . . . . . . . . 328
Winter Tires . . . . . . . . . . . . . . . . . . 328
Low-Profile Tires . . . . . . . . . . . . . 329
All-Terrain Tires . . . . . . . . . . . . . . . 329
Tire Sidewall Labeling . . . . . . . . 329
Tire Designations . . . . . . . . . . . . . 331
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . . . 331
Tire Pressure . . . . . . . . . . . . . . . . . 334
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . 335
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . . . . 336
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . 337
Tire Inspection . . . . . . . . . . . . . . . . 340
Tire Rotation . . . . . . . . . . . . . . . . . 340
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When It Is Time for NewTires . . . . . . . . . . . . . . . . . . . . . . . . 341
Buying New Tires . . . . . . . . . . . . . 342
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . . 343
Uniform Tire Quality Grading . . . . . . . . . . . . . . . . . . . . . 344
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . . 345
Wheel Replacement . . . . . . . . . . 345
Tire Chains . . . . . . . . . . . . . . . . . . . 346
If a Tire Goes Flat . . . . . . . . . . . . 347
Tire Changing . . . . . . . . . . . . . . . . 348
Full-Size Spare Tire . . . . . . . . . . 357
Jump Starting
Jump Starting - North America . . . . . . . . . . . . . . . . . . . . . 358
Towing the Vehicle
Towing the Vehicle . . . . . . . . . . . 361
Recreational VehicleTowing . . . . . . . . . . . . . . . . . . . . . . 362
Appearance Care
Exterior Care . . . . . . . . . . . . . . . . . 366
Interior Care . . . . . . . . . . . . . . . . . . 370
Floor Mats . . . . . . . . . . . . . . . . . . . . 374
General Information
For service and parts needs, visit
your dealer. You will receive
genuine GM parts and GM-trained
and supported service people.
Genuine GM parts have one of
these marks:
California Proposition
65 Warning
WARNING: Most motor vehicles,
including this one, as well as many
of its service parts and fluids,
contain and/or emit chemicals
known to the State of California to cause cancer and birth defects or
other reproductive harm. Engine
exhaust, many parts and systems,
many fluids, and some component
wear by-products contain and/or
emit these chemicals.
See
Battery - North America 0307
and Jump Starting - North America
0 358.
California Perchlorate
Materials Requirements
Certain types of automotive
applications, such as airbag
initiators, safety belt pretensioners,
and lithium batteries contained in
Remote Keyless Entry transmitters,
may contain perchlorate materials.
Special handling may be necessary.
For additional information, see
www.dtsc.ca.gov/hazardouswaste/
perchlorate.
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286 Vehicle Care
Accessories and
Modifications
Adding non-dealer accessories or
making modifications to the vehicle
can affect vehicle performance and
safety, including such things as
airbags, braking, stability, ride and
handling, emissions systems,
aerodynamics, durability, and
electronic systems like antilock
brakes, traction control, and stability
control. These accessories or
modifications could even cause
malfunction or damage not covered
by the vehicle warranty.
Damage to suspension components
caused by modifying vehicle height
outside of factory settings will not be
covered by the vehicle warranty.Damage to vehicle components
resulting from modifications or the
installation or use of non-GM
certified parts, including control
module or software modifications, is
not covered under the terms of the
vehicle warranty and may affect
remaining warranty coverage for
affected parts.
GM Accessories are designed to
complement and function with other
systems on the vehicle. See your
dealer to accessorize the vehicle
using genuine GM Accessories
installed by a dealer technician.
Also, see
Adding Equipment to the
Airbag-Equipped Vehicle 098.
Vehicle Checks
Doing Your Own
Service Work
{Warning
It can be dangerous to work on
your vehicle if you do not have
the proper knowledge, service
manual, tools, or parts. Always
follow owner ’s manual procedures
and consult the service manual
for your vehicle before doing any
service work.
If doing some of your own service
work, use the proper service
manual. It tells you much more
about how to service the vehicle
than this manual can. To order the
proper service manual, see Service
Publications Ordering Information
0 402.
This vehicle has an airbag system.
Before attempting to do your own
service work, see Servicing the
Airbag-Equipped Vehicle 097.
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Keep a record with all parts receipts
and list the mileage and the date of
any service work performed. See
Maintenance Records0389.
Caution
Even small amounts of
contamination can cause damage
to vehicle systems. Do not allow
contaminants to contact the fluids,
reservoir caps, or dipsticks.
Hood
To open the hood:
1. Pull the handle with this symbol
on it. It is inside the vehicle
under the steering wheel.
2. Go to the front of the vehicle tofind the secondary hood
release. The handle is under
the front edge of the hood near
the center. Push the handle to
the right and at the same time
raise the hood. Before closing the hood, be sure all
the filler caps are on properly. Then
bring the hood from full open to
within 15 cm (6 in) from the closed
position, pause, and push the front
center of the hood with a swift, firm
motion to fully close the hood.