2009 BUICK LACROSSE brake sensor

When the System Does Not Seem to
Work Properly
The ultrasonic sensors are not clean, a red URPA
display light may illuminate when the vehicle is in
R (Reverse). Keep the rear bumper free of
mud, dirt, snow, ice and slush. For cleaning
instructions, seeWashing Your Vehicle on
page 5-93.
A trailer was attached to the vehicle, or a bicycle or
an object was hanging out of the trunk during the
last drive cycle, the red light may illuminate.
Once the attached object is removed, URPA will
return to normal operation.
A tow bar is attached to the vehicle.
The vehicle’s bumper is damaged. Take the vehicle
to your dealer/retailer to repair the system.
Other conditions may affect system performance,
such as vibrations from a jackhammer or the
compression of air brakes on a very large truck.
If the system is still disabled, after driving forward at
least 15 mph (25 km/h), take the vehicle to your
dealer/retailer.
OnStar®System
OnStar uses several innovative technologies and live
advisors to provide a wide range of safety, security,
information, and convenience services. If the airbags
deploy, the system is designed to make an automatic
call to OnStar Emergency advisors who can request
emergency services be sent to your location. If
the keys are locked in the vehicle, call OnStar at
1-888-4-ONSTAR to have a signal sent to unlock
the doors. OnStar Hands-Free Calling, including
30 trial minutes good for 60 days, is available on most
vehicles. OnStar Turn-by-Turn Navigation service,
with one trial route, is available on most vehicles. Press
the OnStar button to have an OnStar advisor contact
Roadside Service.
OnStar service is provided subject to the OnStar Terms
and Conditions included in the OnStar Subscriber
glove box literature.
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2(Headlamps):Turn the control to this position to
turn on the headlamps together with the following lamps
listed below.
A warning chime will sound if the driver’s door is
opened when the ignition switch is turned to LOCK/OFF
or ACC/ACCESSORY and the headlamps or parking
lamps are on.
Parking Lamps
Taillamps
License Plate Lamps
Instrument Panel Lights
#(Fog lamps) (If Equipped):Push the fog lamps
button to turn them on and off. SeeFog Lamps
on page 3-15for additional information.
Daytime Running Lamps (DRL)/
Automatic Headlamp System
Daytime Running Lamps (DRL) can make it easier for
others to see the front of your vehicle during the day.
DRL can be helpful in many different driving conditions,
but they can be especially helpful in the short periods
after dawn and before sunset. DRL lamps are required
to function at all times on all vehicles rst sold in Canada.
A light sensor on top of the instrument panel makes the
DRL work, so be sure it is not covered.
The DRL system will make the low-beam headlamps
come on at reduced brightness when the following
conditions are met:
The ignition is on.
The exterior lamps control is off.
The parking brake is released.
While the DRL are on, only the vehicle’s low-beam
headlamps will be on at reduced brightness. The turn
signal, taillamps, sidemarker, and other lamps will not
be on. The instrument panel will not be lit up either.
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TPMS Sensor Matching Process
Each TPMS sensor has a unique identication code.
Any time you replace one or more of the TPMS sensors
or rotate the vehicle’s tires, the identication codes need
to be matched to the new tire/wheel position. The sensors
are matched, to the tire/wheel positions, in the following
order: driver side front tire, passenger side front tire,
passenger side rear tire, and driver side rear tire using
a TPMS diagnostic tool. See your dealer/retailer for
service.
The TPMS sensors may also be matched to each
tire/wheel position by increasing or decreasing the tire’s
air pressure. When increasing the tire’s pressure, do
not exceed the maximum ination pressure indicated on
the tire’s sidewall. To decrease the tire’s air-pressure
use the pointed end of the valve cap, a pencil-style
air pressure gage, or a key.
You have two minutes to match each tire and wheel
position. If it takes longer than two minutes to match
any tire and wheel position, the matching process
stops and you need to start over.
The TPMS sensor matching process is outlined below:
1. Set the parking brake.
2. Turn the ignition switch to ON/RUN with the
engine off.3. Press the Remote Keyless Entry (RKE) transmitter’s
LOCK and UNLOCK buttons at the same time for
approximately ve seconds. The horn sounds twice
to signal the receiver is in relearn mode and the
TPMS sensor matching process can begin.
4. Start with the driver side front tire.
5. Remove the valve cap from the tire’s valve
stem. Activate the TPMS sensor by increasing or
decreasing the tire’s air pressure for 10 seconds,
or until a horn chirp sounds. The horn chirp, which
may take up to 30 seconds to sound, conrms that
the sensor identication code has been matched to
the tire/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.
9. After hearing the conrming horn chirp for the driver
side rear tire, the horn chirps two more times to
signal the tire learning process has ended. Turn
the ignition switch to LOCK/OFF.
10. Set all four tires to the recommended air
pressure level as indicated on the tire and loading
information label.
11. Put the valve caps back on the valve stems.
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Wheel Alignment and Tire Balance
The tires and wheels on your vehicle were aligned and
balanced carefully at the factory to give you the longest
tire life and best overall performance. Adjustments to
wheel alignment and tire balancing will not be necessary
on a regular basis. However, if you notice unusual tire
wear or your vehicle pulling to one side or the other, the
alignment might need to be checked. If you notice your
vehicle vibrating when driving on a smooth road, the tires
and wheels might need to be rebalanced. See your
dealer/retailer 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 air, replace it (except some aluminum
wheels, which can sometimes be repaired). See your
dealer/retailer if any of these conditions exist.
Your dealer/retailer will know the kind of wheel
you need.
Each new wheel should have the same load-carrying
capacity, diameter, width, offset, and be mounted
the same way as the one it replaces.If you need to replace any of your wheels, wheel bolts,
wheel nuts, or Tire Pressure Monitor System (TPMS)
sensors, replace them only with new GM original
equipment parts. This way, you will be sure to have
the right wheel, wheel bolts, wheel nuts, and TPMS
sensors for your vehicle.
{CAUTION:
Using the wrong replacement wheels, wheel bolts,
or wheel nuts on your vehicle can be dangerous.
It could affect the braking and handling of your
vehicle, make your tires lose air and make you
lose control. You could have a collision in which
you or others could be injured. Always use the
correct wheel, wheel bolts, and wheel nuts for
replacement.
Notice: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.
SeeChanging a Flat Tire on page 5-76for more
information.
5-74

Mini-Fuses Usage
1 Driver Side High-Beam
2 Passenger Side High-Beam
3 Driver Side Low-Beam
4 Passenger Side Low-Beam
5 Windshield Wiper
Mini-Fuses Usage
6 Washer/Regulated Voltage Control
7 Fog Lamps
8 Transmission Control Module
9 Supplemental Inatable Restraint
10 Auxiliary Power
11 Horn
12 Emission
13 Air Conditioner Clutch
14 Oxygen Sensor
15 Powertrain Control Module
16Powertrain Control Module,
Electronic Throttle Control
17 Electronic Throttle Control
18 Display
19 Antilock Brake Solenoid
20 Fuel Injector
21 Transmission Solenoid
22 Fuel Pump
23 Antilock Brake System
24 Ignition 3.8L V6 Engines
5-102