2008 CADILLAC CTS sensor

Tire Pressure Monitor System
The Tire Pressure Monitor System (TPMS) uses radio
and sensor technology to check tire pressure levels.
The TPMS sensors monitor the air pressure in your
vehicle’s tires and transmit tire pressure readings to
a receiver located in the vehicle.
Each tire, including the spare (if provided), should be
checked monthly when cold and inated to the ination
pressure recommended by the vehicle manufacturer
on the vehicle placard or tire ination pressure label.
(If your vehicle has tires of a different size than the
size indicated on the vehicle placard or tire ination
pressure label, you should determine the proper
tire ination pressure for those tires.)
As an added safety feature, your vehicle has been
equipped with a tire pressure monitoring system (TPMS)
that illuminates a low tire pressure telltale when one
or more of your tires is signicantly under-inated.
Accordingly, when the low tire pressure telltale
illuminates, you should stop and check your tires
as soon as possible, and inate them to the proper
pressure. Driving on a signicantly under-inated
tire causes the tire to overheat and can lead to tire
failure. Under-ination also reduces fuel efficiency and
tire tread life, and may affect the vehicle’s handling
and stopping ability.Please note that the TPMS is not a substitute for proper
tire maintenance, and it is the driver’s responsibility to
maintain correct tire pressure, even if under-ination
has not reached the level to trigger illumination of
the TPMS low tire pressure telltale.
Your vehicle has also been equipped with a TPMS
malfunction indicator to indicate when the system is not
operating properly. The TPMS malfunction indicator is
combined with the low tire pressure telltale. When the
system detects a malfunction, the telltale will ash for
approximately one minute and then remain continuously
illuminated. This sequence will continue upon
subsequent vehicle start-ups as long as the malfunction
exists.
When the malfunction indicator is illuminated, the
system may not be able to detect or signal low tire
pressure as intended. TPMS malfunctions may occur
for a variety of reasons, including the installation of
replacement or alternate tires or wheels on the vehicle
that prevent the TPMS from functioning properly. Always
check the TPMS malfunction telltale after replacing one
or more tires or wheels on your vehicle to ensure that
the replacement or alternate tires and wheels allow the
TPMS to continue to function properly.
SeeTire Pressure Monitor Operation on page 5-70for
additional information.
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Federal Communications
Commission (FCC) and Industry
and Science Canada
The Tire Pressure Monitor System (TPMS) operates
on a radio frequency and complies with Part 15 of
the FCC Rules. Operation is subject to the following
two conditions:
1. This device may not cause harmful interference.
2. This device must accept any interference received,
including interference that may cause undesired
operation.
The TPMS operates on a radio frequency and complies
with RSS-210 of Industry and Science Canada.
Operation is subject to the following two conditions:
1. This device may not cause interference.
2. This device must accept any interference received,
including interference that may cause undesired
operation of the device.
Changes or modications to this system by other than
an authorized service facility could void authorization to
use this equipment.
Tire Pressure Monitor Operation
The Tire Pressure Monitor System (TPMS) is designed
to warn the driver when a low tire pressure condition
exists. TPMS sensors are mounted onto each tire
and wheel assembly, excluding the spare tire and wheel
assembly. The TPMS sensors monitor the air pressure
in the vehicle’s tires and transmits the tire pressure
readings to a receiver located in the vehicle.
Using the Driver Information Center (DIC), the driver
can also check tire pressure levels using the DIC.
For additional information and details about the DIC
operation and displays seeDIC Operation and Displays
on page 3-48andDIC Warnings and Messages on
page 3-56.
When a low tire pressure
condition is detected, the
TPMS illuminates the
low tire pressure warning
light located on the
instrument panel cluster.
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A DIC warning message to check the pressure in a
specic tire is also shown on the DIC display screen.
The low tire pressure warning light and the DIC warning
message come at each ignition cycle until the tires
are inated to the correct ination pressure.
The low tire pressure warning light may come on in
cool weather when the vehicle is rst started, and then
turn off as you start to drive. This could be an early
indicator that the air pressure in the tire(s) are getting
low and need to be inated to the proper pressure.
The Tire and Loading Information label, attached to
your vehicle, shows the size of your vehicle’s original
equipment tires and the correct ination pressure for the
tires when they are cold. SeeLoading the Vehicle on
page 4-22, for an example of the Tire and Loading
Information label and its location on your vehicle.
Also seeInflation - Tire Pressure on page 5-66.Your vehicle’s TPMS can warn you about a low tire
pressure condition but it does not replace normal
tire maintenance. SeeTire Inspection and Rotation
on page 5-74andTires on page 5-58.
Notice:Using non-approved tire sealants could
damage the Tire Pressure Monitor System (TPMS)
sensors. TPMS sensor damage caused by using
an incorrect tire sealant is not covered by the
vehicle warranty. Always use the GM approved
tire sealant available through your dealer/retailer.
Your vehicle, when new, may have included a
factory-installed Tire Sealant and Compressor Kit.
This kit uses a GM approved liquid tire sealant. See
Tire Sealant and Compressor Kit (With Sealant Selector
Switch) on page 5-84orTire Sealant and Compressor
Kit (Without Sealant Selector Switch) on page 5-93.
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TPMS Malfunction Light and Message
The TPMS will not function properly if one or more of
the TPMS sensors are missing or inoperable. When the
system detects a malfunction, the low tire warning light
ashes for about one minute and then stays on for the
remainder of the ignition cycle. A DIC warning message
is also displayed. The low tire warning light and DIC
warning message come on at each ignition cycle until the
problem is corrected. Some of the conditions that can
cause the malfunction light and DIC message to come
on are:
One of the road tires has been replaced with the
spare tire. The spare tire does not have a TPMS
sensor. The DIC message should go off once you
re-install the road tire containing the TPMS sensor.
The TPMS sensor matching process was not
done or not completed successfully after rotating
the vehicle’s tires. The DIC message should go off
after successfully completing the sensor matching
process. See “TPMS Sensor Matching Process”
later in this section.
One or more TPMS sensors are missing or
damaged. The DIC message and the TPMS
malfunction light should go off when the TPMS
sensors are installed and the sensor matching
process is performed successfully. See your
dealer/retailer for service.
Replacement tires or wheels do not match your
vehicle’s original equipment tires or wheels. Tires
and wheels other than those recommended for your
vehicle could prevent the TPMS from functioning
properly. SeeBuying New Tires on page 5-76.
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 it cannot detect or
signal a low tire condition. See your dealer/retailer for
service if the TPMS malfunction light and DIC message
comes on and stays on.
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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 your 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 can also be matched to each
tire/wheel position by increasing or decreasing the tire’s
air pressure. If increasing the tire’s air 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 the rst tire/wheel
position, and ve minutes overall, to match all four
tire/wheel positions. If it takes longer than two minutes,
to match the rst tire and wheel, or more than
ve minutes to match all four tire and wheel positions,
the matching process stops and you need to start over.The TPMS 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 Tire
Learning Active message displays on the DIC
screen.
4. Start with the driver side front tire.
5. Remove the valve cap from the 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
can take up to 30 seconds to sound, conrms
that the TPMS sensor identication code has
been matched to this tire 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.
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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 5-102for more
information.
Used Replacement Wheels
{CAUTION:
Putting a used wheel on the vehicle is
dangerous. You cannot know how it has been
used or how far it has been driven. It could fail
suddenly and cause a crash. If you have to
replace a wheel, use a new GM original
equipment wheel.
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12. The tire is not sealed and will continue to leak
air until the vehicle is driven and the sealant is
distributed in the tire.
Steps 11 through 18 must be done right after
Step 10.
13. Unplug the air compressor accessory plug (F) from
the accessory power outlet in the vehicle.
14. Disconnect the sealant/air hose from the tire valve
stem or tire pressure monitoring sensor cap, by
turning it counterclockwise, and replace the
tire valve stem cap.
Be careful when handling the tire inator
components as they may be hot after usage.
15. Wrap the sealant/air hose around the air
compressor channel to stow it in its original location.
16. Wrap the air compressor accessory plug (E)
back into place.17. If the at tire was
able to inate to the
recommended ination
pressure, remove the
maximum speed label
from the sealant
canister.
Place it in a highly visible location such as the
inside of the upper left corner of the windshield or
to the face of the radio/clock.
The maximum speed label reminds you to drive
cautiously and not to exceed 55 mph (90 km/h) until
you have the damaged tire inspected and repaired.
5-88

Relays Usage
RT/POS/LP Right Position Lamp
SPARE Spare
STOP/LP Stoplamp
TRUNK/RELSE Trunk Release
UNLCK Unlock
Fuses Usage
AIRBAG Airbag System
AMP Amplier
AUX/OUTLET Auxiliary Power Outlet
CNSTR/VENT Canister Vent
DR/LCK Door Lock
ECM Engine Control Module (ECM)
FUEL/PUMP Fuel Pump
LT/POS/LP Left Position Lamp
LT/REAR/
WNDWLeft Rear Window
MSM Memory Seat Module
Fuses Usage
ONSTAR OnStar®System
PDM Passenger Door Module
RDO Audio System
RDO/SPKR Audio Speakers
REAR/FOG Not Used
REAR/WNDW Rear Window
RKE/
PASS-KEY/
MDLRemote Keyless Entry System,
Pass-Key Theft Deterrent Feature
Module
RT/POS/LP Right Position Lamp
RT/POS/LP Right Position Lamp
RVC/SNSR Regulated Voltage Control Sensor
S/ROOF Sunroof
SPARE Spare
SPARE Spare
STOP/LP Stoplamp
THEFT/UGDOTheft Deterrent System, Universal
Home Remote System
TRUNK/RELSE Trunk Release
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