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Brake Fluid
The brake master cylinder reservoir is
filled with GM approved DOT 3 brake
fluid as indicated on the reservoir cap.
SeeEngine Compartment Overview
0 247 for the location of the reservoir.
Checking Brake Fluid
With the vehicle in P (Park) on a level
surface, the brake fluid level should be
between the minimum and maximum
marks on the brake fluid reservoir.
There are only two reasons why the
brake fluid level in the reservoir may
go down:
. Normal brake lining wear. When
new linings are installed, the fluid
level goes back up.
. A fluid leak in the brake hydraulic
system. Have the brake hydraulic
system fixed. With a leak, the
brakes will not work well. Always clean the brake fluid reservoir
cap and the area around the cap
before removing it.
Do not top off the brake fluid. Adding
fluid does not correct a leak. If fluid is
added when the linings are worn,
there will be too much fluid when
new brake linings are installed. Add or
remove fluid, as necessary, only when
work is done on the brake hydraulic
system.
{Warning
If too much brake fluid is added, it
can spill on the engine and burn,
if the engine is hot enough. You or
others could be burned, and the
vehicle could be damaged. Add
brake fluid only when work is done
on the brake hydraulic system.
When the brake fluid falls to a low
level, the brake warning light comes
on. See Brake System Warning
Light 0129.
Brake fluid absorbs water over time
which degrades the effectiveness of
the brake fluid. Replace brake fluid at the specified intervals to prevent
increased stopping distance. See
Maintenance Schedule
0311.
What to Add
Use only GM approved DOT 3 brake
fluid from a clean, sealed container.
See Recommended Fluids and
Lubricants 0318.
{Warning
The wrong or contaminated brake
fluid could result in damage to the
brake system. This could result in
the loss of braking leading to a
possible injury. Always use the
proper GM approved brake fluid.
Caution
If brake fluid is spilled on the
vehicle's painted surfaces, the paint
finish can be damaged. Immediately
wash off any painted surface.

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All-Wheel Drive
If the vehicle is equipped with
All-Wheel Drive (AWD), this is an
additional system that needs
lubrication.
Transfer Case
When to Check Lubricant
It is not necessary to regularly check
the transfer case fluid unless a leak is
suspected or an unusual noise is
heard. A fluid loss could indicate a
problem. Have it inspected and
repaired.
How to Check Lubricant
1. Fill Plug
2. Drain Plug
To get an accurate reading, the vehicle
should be on a level surface.
If the level is below the bottom of the
fill plug hole on the transfer case,
some lubricant will need to be added.
Add enough lubricant to raise the
level to the bottom of the fill plug
hole. Use care not to overtighten the
fill plug.
What to Use
To determine what kind of lubricant
to use, seeRecommended Fluids and
Lubricants 0318.
Starter Switch Check
{Warning
When you are doing this inspection,
the vehicle could move suddenly.
If the vehicle moves, you or others
could be injured.
1. Before starting this check, be sure there is enough room
around the vehicle. 2. Firmly apply both the parking
brake and the regular brake. Do
not use the accelerator pedal,
and be ready to turn off the
engine immediately if it starts.
3. Try to start the engine in each gear. The vehicle should start
only in P (Park) or N (Neutral).
If the vehicle starts in any other
position, contact your dealer for
service.
Automatic Transmission
Shift Lock Control Function
Check
{Warning
When you are doing this inspection,
the vehicle could move suddenly.
If the vehicle moves, you or others
could be injured.
1. Before starting this check, be sure there is enough room
around the vehicle. It should be
parked on a level surface.

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2. Firmly apply the parking brake.See Electric Parking Brake 0205.
Be ready to apply the regular
brake immediately if the vehicle
begins to move.
3. With the engine off, turn the ignition on, but do not start the
engine. Without applying the
regular brake, try to move the
shift lever out of P (Park) with
normal effort. If the shift lever
moves out of P (Park), contact
your dealer for service.
Park Brake and P (Park)
Mechanism Check
{Warning
When you are doing this check, the
vehicle could begin to move. You or
others could be injured and
property could be damaged. Make
sure there is room in front of the
vehicle in case it begins to roll. Be
ready to apply the regular brake at
once should the vehicle begin
to move. Park on a fairly steep hill, with the
vehicle facing downhill. Keeping your
foot on the regular brake, set the
parking brake.
.
To check the parking brake's
holding ability: With the engine
running and the transmission in
N (Neutral), slowly remove foot
pressure from the regular brake
pedal. Do this until the vehicle is
held by the parking brake only.
. To check the P (Park) mechanism's
holding ability: With the engine
running, shift to P (Park). Then
release the parking brake followed
by the regular brake.
Contact your dealer if service is
required.Wiper Blade Replacement
Windshield wiper blades should be
inspected for wear or cracking.
For the proper type and size, see
Maintenance Replacement Parts 0319. To replace the wiper blade assembly:
1. Pull the windshield wiper assembly away from the
windshield.
2. Lift up on the latch in the middleof the wiper blade where the
wiper arm attaches.
3. With the latch open, pull the wiper blade down toward the
windshield far enough to release
it from the J-hooked end of the
wiper arm.
4. Remove the wiper blade.

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Number Usage21 A/C clutch
22 –
23 Coolant heater control module
24 Coolant pump
25 Coolant pump relay
26 Hi fuel
27 Steering column lock
28 Rear heated seats
29 Front heated seats
30 –
31 LED LGT battery
32 A/C control module
33 AIR solenoid
34 –
35 Engine control module
36 Engine control module 2
37 Coolant pump/ Ignition coils –odd Number Usage
38 Ignition coils –even/
Non walk 2
39 Non walk
40 Instrument cluster
41 –
42 Fuel pump power module
43 Instrument panel body/Ignition
44 Aeroshutter
45 Washer
46 Front sensor
47 Left cornering LED
48 AIR solenoid relay
49 Air pump relay
50 Engine control module relay
51 Wiper speed relay
52 Wiper control relay
53 Headlamp control relay
54 – Number Usage
55 –
56 Air pump
57 –
58 Instrument panel electronic center
59 –
60 ABS pump
61 Front wiper
62 Headlamp leveling
63 Electric brake booster module
64 –
65 –
66 Transfer case control module
67 Electric brake booster
68 Rear seat entertainment
display
69 RESS coolant pump
70 –
71 ABS valve

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light and the DIC message should
go off after successfully
completing the sensor matching
process. See "TPMS Sensor
Matching Process" following.
. One or more TPMS sensors are
missing or damaged. The
malfunction light and the DIC
message should go off when the
TPMS sensors are installed and
the sensor matching process is
performed successfully. See your
dealer for service.
. Replacement tires or wheels do
not match the original equipment
tires or wheels. Tires and wheels
other than those recommended
could prevent the TPMS from
functioning properly. See Buying
New Tires 0286.
. Operating electronic devices or
being near facilities using radio
wave frequencies similar to the
TPMS could cause the TPMS
sensors to malfunction.
If the TPMS is not functioning
properly, it cannot detect or signal a
low tire condition. See your dealer for service if the TPMS malfunction light
and DIC message come on and
stay on.
TPMS Sensor Matching Process
Each TPMS sensor has a unique
identification code. The identification
code needs to be matched to a new
tire/wheel position after rotating the
vehicle’s tires or replacing one or more
of the TPMS sensors. The TPMS
sensor matching process should also
be performed after replacing a spare
tire with a road tire containing the
TPMS sensor. The malfunction light
and the DIC message should go off at
the next ignition cycle. The sensors
are matched to the tire/wheel
positions, using a TPMS relearn tool,
in the following order: driver side
front tire, passenger side front tire,
passenger side rear tire, and driver
side rear tire. See your dealer for
service or to purchase a relearn tool.
There are two minutes to match the
first tire/wheel position, and
five minutes overall to match all four
tire/wheel positions. If it takes longer,
the matching process stops and must
be restarted.The TPMS sensor matching process is:
1. Set the parking brake.
2. Place the vehicle power mode in ON/RUN/START. See Ignition
Positions 0195.
3. Make sure the Tire Pressure info display option is turned on. The
info displays on the DIC can be
turned on and off through the
Settings menu. See Driver
Information Center (DIC) 0136.
4. Use the five-way DIC control on the right side of the steering
wheel to scroll to the Tire
Pressure screen under the DIC
info page. See Driver Information
Center (DIC) 0136.
5. Press and hold SEL in the center of the five-way DIC control.
The horn sounds twice to signal
the receiver is in relearn mode
and the TIRE LEARNING ACTIVE
message displays on the DIC
screen.
6. Start with the driver side front tire.

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on the flat wheel mounting
surface or on the wheel nuts or
bolts.
When It Is Time for New
Tires
Factors such as maintenance,
temperatures, driving speeds, vehicle
loading, and road conditions affect the
wear rate of the tires.
Treadwear indicators are one way to
tell when it is time for new tires.
Treadwear indicators appear when the
tires have only 1.6 mm (1/16 in) orless of tread remaining. See
Tire
Inspection 0284 and Tire
Rotation 0284.
The rubber in tires ages over time.
This also applies to the spare tire,
if the vehicle has one, even if it is
never used. Multiple factors including
temperatures, loading conditions, and
inflation pressure maintenance affect
how fast aging takes place. GM
recommends that tires, including the
spare if equipped, be replaced after six
years, regardless of tread wear. The
tire manufacture date is the last four
digits of the DOT Tire Identification
Number (TIN) which is molded into
one side of the tire sidewall. The first
two digits represent the week (01–52)
and the last two digits, the year. For
example, the third week of the year
2010 would have a four-digit DOT
date of 0310.
Vehicle Storage
Tires age when stored normally
mounted on a parked vehicle. Park a
vehicle that will be stored for at least
a month in a cool, dry, clean area
away from direct sunlight to slow aging. This area should be free of
grease, gasoline, or other substances
that can deteriorate rubber.
Parking for an extended period can
cause flat spots on the tires that may
result in vibrations while driving.
When storing a vehicle for at least a
month, remove the tires or raise the
vehicle to reduce the weight from the
tires.
Buying New Tires
GM has developed and matched
specific tires for the vehicle. The
original equipment tires installed
were designed to meet General
Motors Tire Performance Criteria
Specification (TPC Spec) system
rating. When replacement tires are
needed, GM strongly recommends
buying tires with the same TPC
Spec rating.
GM's exclusive TPC Spec system
considers over a dozen critical
specifications that impact the
overall performance of the vehicle,
including brake system

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Warning (Continued)
and cause a crash. Use only
radial-ply tires with the wheels
on the vehicle.
If the vehicle tires must be
replaced with a tire that does not
have a TPC Spec number, make
sure they are the same size, load
range, speed rating, and
construction type (radial) as the
original tires.
Vehicles that have a tire pressure
monitoring system could give an
inaccurate low-pressure warning if
non-TPC Spec rated tires are
installed. See Tire Pressure Monitor
Operation 0281.
The Tire and Loading Information
label indicates the original
equipment tires on the vehicle.
See Vehicle Load Limits 0191, for
the label location and more
information about the Tire and
Loading Information label.Different Size Tires and
Wheels
If wheels or tires are installed that are
a different size than the original
equipment wheels and tires, vehicle
performance, including its braking,
ride and handling characteristics,
stability, and resistance to rollover
may be affected. If the vehicle has
electronic systems such as antilock
brakes, rollover airbags, traction
control, electronic stability control,
or All-Wheel Drive, the performance
of these systems can also be affected.
{Warning
If different sized wheels are used,
there may not be an acceptable
level of performance and safety if
tires not recommended for those
wheels are selected. This increases
the chance of a crash and serious
injury. Only use GM specific wheel
and tire systems developed for the
vehicle, and have them properly
installed by a GM certified
technician. See
Buying New Tires 0286 and
Accessories and Modifications 0245.
Wheel Alignment and Tire
Balance
The tires and wheels were aligned and
balanced at the factory to provide the
longest tire life and best overall
performance. Adjustments to wheel
alignment and tire balancing are not
necessary on a regular basis. Consider
an alignment check if there is unusual
tire wear or the vehicle is significantly
pulling to one side or the other. Some
slight pull to the left or right,
depending on the crown of the road
and/or other road surface variations
such as troughs or ruts, is normal.
If the vehicle is vibrating when driving
on a smooth road, the tires and
wheels may need to be rebalanced.
See your dealer for proper diagnosis.
Wheel Replacement
Replace any wheel that is bent,
cracked, or badly rusted or corroded.
If wheel nuts keep coming loose, the
wheel, wheel bolts, and wheel nuts
should be replaced. If the wheel leaks

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air, replace it. Some aluminum wheels
can be repaired. See your dealer if any
of these conditions exist.
Your dealer will know the kind of
wheel that is needed.
Each new wheel should have the same
load-carrying capacity, diameter,
width, offset, and be mounted the
same way as the one it replaces.
Replace wheels, wheel bolts, wheel
nuts, or Tire Pressure Monitor System
(TPMS) sensors with new GM original
equipment parts.
{Warning
Using the wrong replacement
wheels, wheel bolts, or wheel nuts
can be dangerous. It could affect
the braking and handling of the
vehicle. Tires can lose air, and
cause loss of control, causing a
crash. Always use the correct wheel,
wheel bolts, and wheel nuts for
replacement.
Caution
The wrong wheel can also cause
problems with bearing life, brake
cooling, speedometer or odometer
calibration, headlamp aim, bumper
height, vehicle ground clearance,
and tire or tire chain clearance to
the body and chassis.
Used Replacement Wheels
{Warning
Replacing a wheel with a used one
is dangerous. How it has been used
or how far it has been driven may
be unknown. It could fail suddenly
and cause a crash. When replacing
wheels, use a new GM original
equipment wheel.
Tire Chains
Caution
Use tire chains only where legal and
only when necessary. Use low
profile chains that add no more
than 10 mm thickness to the tire
tread and inner sidewall. Use chains
that are the proper size for the tires.
Install them on the tires of the rear
axle. Do not use chains on the tires
of the front axle. Tighten them as
tightly as possible with the ends
securely fastened. Drive slowly and
follow the chain manufacturer's
instructions. If the chains contact
the vehicle, stop and retighten
them. If the contact continues, slow
down until it stops. Driving too fast
or spinning the wheels with chains
on will damage the vehicle.
If a Tire Goes Flat
It is unusual for a tire to blow out
while driving, especially if the tires are
maintained properly. SeeTires0276.
If air goes out of a tire, it is much