brake GMC ACADIA 2012 Service Manual

Black plate (23,1)GMC Acadia/Acadia Denali Owner Manual - 2012
Vehicle Care 10-23
{WARNING
The brake wear warning sound
means that soon the brakes will
not work well. That could lead to
a crash. When the brake wear
warning sound is heard, have the
vehicle serviced.
Notice: Continuing to drive with
worn-out brake pads could result
in costly brake repair.
Some driving conditions or climates
can cause a brake squeal when the
brakes are first applied or lightly
applied. This does not mean
something is wrong with the 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 torque
specifications in
Capacities and
Specifications on page 12‑2.
Brake linings should always be
replaced as complete axle sets.
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
that brake service might be
required.
Brake Adjustment
Every time the brakes are applied,
with or without the vehicle moving,
the brakes adjust for wear.
Replacing Brake System Parts
The braking system on a vehicle is
complex. Its many parts have to be
of top quality and work well together
if the vehicle is to have really good
braking. The vehicle was designed
and tested with top-quality brake
parts. When parts of the braking
system are replaced, be sure to get
new, approved replacement parts.
If this is not done, the brakes might
not work properly. For example,
installing disc brake pads that are
wrong for the vehicle, can change
the balance between the front
and rear brakes— for the worse.
The braking performance expected
can change in many other ways if
the wrong replacement brake parts
are installed.

Black plate (24,1)GMC Acadia/Acadia Denali Owner Manual - 2012
10-24 Vehicle Care
Brake Fluid
The brake master cylinder reservoir
is filled with DOT 3 brake fluid as
indicated on the reservoir cap.
SeeEngine Compartment Overview
on page 10‑6 for the location of the
reservoir.
There are only two reasons why the
brake fluid level in the reservoir
might go down:
.The brake fluid level goes down
because of normal brake lining
wear. When new linings are
installed, the fluid level goes
back up.
.A fluid leak in the brake
hydraulic system can also cause
a low fluid level. Have the brake
hydraulic system fixed, since a
leak means that sooner or later
the brakes will not work well.
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 brake 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 on page 5‑21.
What to Add
Use only new DOT 3 brake fluid
from a sealed container. See
Recommended Fluids and
Lubricants on page 11‑12.
Always clean the brake fluid
reservoir cap and the area
around the cap before removing it.
This helps keep dirt from entering
the reservoir.{WARNING
With the wrong kind of fluid in
the brake hydraulic system, the
brakes might not work well.
This could cause a crash.
Always use the proper brake fluid.

Black plate (25,1)GMC Acadia/Acadia Denali Owner Manual - 2012
Vehicle Care 10-25
Notice
.Using the wrong fluid can
badly damage brake
hydraulic system parts.
For example, just a few
drops of mineral-based oil,
such as engine oil, in the
brake hydraulic system can
damage brake hydraulic
system parts so badly that
they will have to be replaced.
Do not let someone put in
the wrong kind of fluid.
.If brake fluid is spilled on the
vehicle's painted surfaces,
the paint finish can be
damaged. Be careful not to
spill brake fluid on the
vehicle. If you do, wash it off
immediately.
Battery
Refer to the replacement number on
the original battery label when a
new battery is needed.
{WARNING
Battery posts, terminals, and
related accessories contain lead
and lead compounds, chemicals
known to the State of California to
cause cancer and reproductive
harm. Wash hands after handling.
Vehicle Storage
{WARNING
Batteries have acid that can burn
you and gas that can explode.
You can be badly hurt if you are
not careful. SeeJump Starting on
page 10‑78 for tips on working
around a battery without
getting hurt.
Infrequent Usage: Remove the
black, negative (−) cable from the
battery to keep the battery from
running down.
Extended Storage: Remove the
black, negative (−) cable from the
battery or use a battery trickle
charger.

Black plate (26,1)GMC Acadia/Acadia Denali Owner Manual - 2012
10-26 Vehicle Care
All-Wheel Drive
It is not necessary to check the
all-wheel drive lubricant levels.
A fluid leak is the only reason for
fluid loss. If a leak occurs, take the
vehicle to the dealer as soon as
possible.
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.
See Parking Brake on
page 9‑28. 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.
2. Firmly apply the parking brake. See Parking Brake on
page 9‑28.
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.

Black plate (27,1)GMC Acadia/Acadia Denali Owner Manual - 2012
Vehicle Care 10-27
Ignition Transmission
Lock Check
While parked, and with the parking
brake set, try to turn the ignition to
LOCK/OFF in each shift lever
position.
.The ignition should turn to
LOCK/OFF only when the shift
lever is in P (Park).
.The ignition key should come
out only in LOCK/OFF.
Contact your dealer if service is
required.
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.

Black plate (32,1)GMC Acadia/Acadia Denali Owner Manual - 2012
10-32 Vehicle Care
The vehicle may not be equipped
with all of the fuses, relays, and
features shown.Fuses Usage
A/C CLTCH Air Conditioning
Clutch
ABS MTR Antilock Brake
System (ABS)
Motor
AFS Adaptive Forward
Lighting System
AIRBAG Airbag System
AUX POWER Auxiliary Power
AUX
VAC PUMP Auxiliary
Vacuum Pump
AWD All-Wheel-Drive
System
BATT 1 Battery 1
BATT 2 Battery 2
BATT 3 Battery 3 CIGAR
LIGHTER Cigarette Lighter
ECM Engine Control
Module

Black plate (34,1)GMC Acadia/Acadia Denali Owner Manual - 2012
10-34 Vehicle Care
FusesUsage
STRTR Starter
TCM Transmission
Control Module
TRANS Transmission TRLR
BCK/UP Trailer Back‐up
Lamps
TRLR BRK Trailer Brake TRLR
PRK LAMP Trailer Parking
Lamps
TRLR PWR Trailer Power
WPR/WSW Windshield
Wiper/Washer
Relays Usage
A/C
CMPRSR CLTCH Air Conditioning
Compressor Clutch
AUX
VAC PUMP Auxiliary
Vacuum Pump
CRNK Switched Power Relays
Usage
FAN 1 Cooling Fan 1
FAN 2 Cooling Fan 2
FAN 3 Cooling Fan 3
FOG LAMP Fog Lamps
HI BEAM High‐Beam
Headlamps
HID/LO BEAM High Intensity
Discharge (HID)
Low‐Beam
Headlamps
HORN Horn IGN Ignition Main
LT TRLR
STOP/TRN Trailer Left
Stoplamp and
Turn Signal Lamp
PRK LAMP Parking Lamp
PWR/TRN Powertrain
RR DEFOG Rear Window
Defogger Relays
Usage
RT TRLR
STOP/TRN Trailer Right
Stoplamp and
Turn Signal Lamp
Stop Lamps
(China Only) Stop Lamps
(China Only)
TRLR
BCK/UP Trailer Back-up
Lamps
WPR Windshield Wiper
WPR HI Windshield Wiper
High Speed
Instrument Panel Fuse
Block
The instrument panel fuse block
is located under the instrument
panel on the passenger side of the
vehicle. Pull down on the cover to
access the fuse block.

Black plate (41,1)GMC Acadia/Acadia Denali Owner Manual - 2012
Vehicle Care 10-41
Accessory Weight:The
combined weight of optional
accessories. Some examples
of optional accessories are
automatic transmission, power
steering, power brakes, power
windows, power seats, and air
conditioning.
Aspect Ratio
:The relationship
of a tire's height to its width.
Belt
:A rubber coated layer of
cords that is located between
the plies and the tread. Cords
may be made from steel or other
reinforcing materials.
Bead
:The tire bead contains
steel wires wrapped by steel
cords that hold the tire onto
the rim. Bias Ply Tire
:A pneumatic tire
in which the plies are laid at
alternate angles less than
90 degrees to the centerline of
the tread.
Cold Tire Pressure
:The
amount of air pressure in a tire,
measured in kPa (kilopascal)
or psi (pounds per square inch)
before a tire has built up heat
from driving. See Tire Pressure
on page 10‑44.
Curb Weight
:The weight of a
motor vehicle with standard and
optional equipment including
the maximum capacity of fuel,
oil, and coolant, but without
passengers and cargo.
DOT Markings
:A code
molded into the sidewall of a
tire signifying that the tire is in
compliance with the U.S.
Department of Transportation (DOT) Motor Vehicle Safety
Standards. The DOT code
includes the Tire Identification
Number (TIN), an alphanumeric
designator which can also
identify the tire manufacturer,
production plant, brand, and
date of production.
GVWR
:Gross Vehicle Weight
Rating. See Vehicle Load Limits
on page 9‑10.
GAWR FRT
:Gross Axle
Weight Rating for the front axle.
See Vehicle Load Limits on
page 9‑10.
GAWR RR
:Gross Axle
Weight Rating for the rear axle.
See Vehicle Load Limits on
page 9‑10.

Black plate (49,1)GMC Acadia/Acadia Denali Owner Manual - 2012
Vehicle Care 10-49
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. 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. Turn the ignition to ON/RUNwith the engine off. 3. Press the Remote Keyless Entry
(RKE) transmitter's LOCK and
UNLOCK buttons at the same
time for approximately
five seconds. The horn sounds
twice to signal the receiver is in
relearn mode and TIRE
LEARNING ACTIVE message
displays on the DIC screen.
4. Start with the driver side front tire.
5. Place the relearn tool against the tire sidewall, near the valve
stem. Then press the button to
activate the TPMS sensor.
A horn chirp confirms that the
sensor identification code has
been matched to this tire and
wheel position.
6. Proceed to the passenger side front tire, and repeat the
procedure in Step 5. 7. Proceed to the passenger side
rear tire, and repeat the
procedure in Step 5.
8. Proceed to the driver side rear tire, and repeat the procedure in
Step 5. The horn sounds two
times to indicate the sensor
identification code has been
matched to the driver side rear
tire, and the TPMS sensor
matching process is no longer
active. The TIRE LEARNING
ACTIVE message on the DIC
display screen goes off.
9. Turn the ignition to LOCK/OFF.
10. Set all four tires to the recommended air pressure
level as indicated on the Tire
and Loading Information label.

Black plate (52,1)GMC Acadia/Acadia Denali Owner Manual - 2012
10-52 Vehicle Care
The rubber in tires ages over time.
This also applies for the spare tire,
if the vehicle has one, even if it is
never used. Multiple conditions
including temperatures, loading
conditions, and inflation pressure
maintenance affect how fast aging
takes place. Tires will typically need
to be replaced due to wear before
they may need to be replaced
due to age. Consult the tire
manufacturer for more information
on when tires should be replaced.
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 performance, ride and
handling, traction control, and
tire pressure monitoring
performance. GM's TPC Spec
number is molded onto the tire's
sidewall near the tire size. If the
tires have an all‐season tread
design, the TPC Spec number
will be followed by MS for mud
and snow. See
Tire Sidewall
Labeling on page 10‑38 for
additional information.
GM recommends replacing
all the tires at the same time.
Uniform tread depth on all
tires will help to maintain the
performance of the vehicle.