2005 CADILLAC STS brake sensor

Twilight Sentinel®
Twilight Sentinel®can turn your lamps on and off for you.
A light sensor on top of the instrument panel makes the
Twilight Sentinel
®work, so be sure it is not covered.
With Twilight Sentinel
®you will see the following
happen:
When it is dark enough outside, the front turn signal
lamps (DRL) will go off, and the headlamps and
parking lamps will come on. The other lamps
that come on with headlamps will also come on.
When it is bright enough outside, the headlamps
will go off, and the front turn signal lamps (DRL)
will come on, as long as the exterior lamp switch is
in the off position.
If you start your vehicle in a dark garage, the automatic
headlamp system will come on immediately. Once
you leave the garage, it will take approximately
one minute for the automatic headlamp system to
change to DRL if it is light outside. During that delay,
your instrument panel cluster may not be as bright
as usual. Make sure your instrument panel brightness
control is in full bright position. SeeInstrument Panel
Brightness on page 3-41for more information.
You can idle the vehicle with the lamps off, even when
it is dark outside. First set the parking brake while
the ignition is in OFF/ACC. Then start the vehicle. The
lamps will stay off until you release the parking
brake.
Twilight Sentinel
®also provides exterior illumination as
you leave the vehicle. If Twilight Sentinel®has turned
on the lamps when you turn off the ignition, your lamps
will remain on until:
The exterior lamp switch is moved from off to the
parking lamp position, or
a delay time that you select has elapsed.
3-40

The URPA display is
located inside the vehicle,
above the rear window.
It has three color-coded
lights that can be seen
through the rearview mirror
or by turning around.
How the System Works
URPA comes on automatically when the shift lever is
moved into REVERSE (R) and the vehicle speed is less
than 3 mph (5 km/h). When the system turns on, the
three lights on the display will illuminate for one and
a half seconds to let you know that the system is
working. If your vehicle is moving in REVERSE (R) at
a speed greater than 3 mph (5 km/h), the red light
will ash to remind you that the system does not work
at a speed greater than 3 mph (5 km/h).If an object is detected at a REVERSE (R) speed of
less than 3 mph (5 km/h), one of the following will occur:
Description English Metric
Amber light 5 ft 1.5 m
Amber/amber lights 40 in 1.0 m
Amber/amber/red lights &
continuous chime20 in 0.5 m
Amber/amber/red lights
ashing & continuous
chime1 ft 0.3 m
A chime will sound the rst time an object is detected
between 20 inches (0.5 m) and 5 feet (1.5 m) away.
URPA cannot detect objects that are above trunk level.
In order for the rear sensors to recognize an object,
it must be within detection range behind the vehicle.
When the System Does Not Seem to Work
Properly
The light may ash red when the vehicle is in
REVERSE (R), if the ultrasonic sensors are not kept
clean. So be sure to keep your rear bumper free of mud,
dirt, snow, ice and slush. Other conditions that may affect
system performance include things like the vibrations
from a jackhammer or the compression of air brakes on a
very large truck. If after cleaning the rear bumper and
then driving forward at least 15 mph (25 km/h), the
display continues to ash red, see your dealer.
3-48

PRESS START AND BRAKE TO START
ENGINE
When this message displays, it means that you need to
press down on the brake pedal while pressing the
start button on the electronic keyless ignition when trying
to start your vehicle. SeeStarting the Engine on
page 2-24for more information.
RADAR CRUISE NOT READY
When this message displays, it means that the Adaptive
Cruise Control system will not activate due to a
temporary condition. Your vehicle does not require
service. This message will also display when either of
the following conditions occurs:
The driver turns off the head-up display (HUD)
while the Adaptive Cruise Control is engaged.
The driver attempts to engage the Adaptive Cruise
Control while the HUD is off.
If this message appears when you attempt to activate
the system, continue driving for several minutes
and then try activating the system again.
RIGHT REAR DOOR AJAR
This symbol appears with
the RIGHT REAR DOOR
AJAR message.
When this message displays, it means that the
passenger’s side rear door was not closed completely.
You should check to make sure that the door is
closed completely.
SERVICE AC (Air Conditioning)
SYSTEM
This message will display when the electronic sensors
that control the air conditioning and heating systems are
no longer working. Have the climate control system
serviced by your GM dealer if you notice a drop
in heating and air conditioning efficiency.
3-87

The traction control system automatically comes on
whenever you start your vehicle. To limit wheel
spin, especially in slippery road conditions, you should
always leave the system on. But you can turn the
traction control system off if you ever need to.
Notice:Do not repeatedly brake or accelerate
heavily when the TCS is off. You could damage your
vehicle’s driveline.
When the TCS is switched off on AWD vehicles, you
may still feel the system working. This is normal
and necessary with the AWD hardware on your vehicle.
You should turn the system off if your vehicle ever
gets stuck in sand, mud or snow and rocking the vehicle
is required. SeeRocking Your Vehicle to Get It Out
on page 4-30andIf Your Vehicle is Stuck in Sand, Mud,
Ice or Snow on page 4-29for more information. See
alsoWinter Driving on page 4-25for information
on using TCS when driving in snowy or icy conditions.
To turn the system off,
press the TC (traction
control) button located
near the shift lever.If you press the TC button once, the traction control
system will turn off and the traction control system
warning light will come on. Press the TC button again to
turn the system back on. If you press and hold the
TC button for ve seconds, the StabiliTrak
®system and
the traction control system will turn off. Press the
TC button again to turn StabiliTrak
®back on. For more
information, seeStabiliTrak®System on page 4-10.
Magnetic Ride Control
Your vehicle may have Magnetic Ride Control that
automatically adjusts the ride of your vehicle. Automatic
ride control is achieved through a computer used to
control and monitor the suspension system. The
controller receives input from various sensors to
determine the proper system response. If the controller
detects a problem within the system, the DIC will
display a Service Suspension System message. See
DIC Warnings and Messages on page 3-78for
more information. See your dealer for service.
Limited-Slip Rear Axle
Your limited-slip rear axle can give you additional traction
on snow, mud, ice, sand or gravel. It works like a
standard axle most of the time, but when one of the rear
wheels has no traction and the other does, this feature
will allow the wheel with traction to move the vehicle.
4-9

TPM Sensor Identication Codes
Each TPM sensor has a unique identication code. Any
time you replace one or more of the TPM sensors or
rotate your vehicle’s tires, the identication codes
will need to be matched to the new tire/wheel position.
The sensors are matched, to the tire/wheel positions,
in the following order: left front (LF), right front (RF), right
rear (RR), and left rear (LR) using a TPM diagnostic
tool. See your GM dealer for service.
The TPM sensors may also be matched to each
tire/wheel position by increasing or decreasing the tire’s
air pressure. If using this method to match TPM
sensors, the complete procedure outlined below must
be performed after the vehicle has been driven at
least 20 mph (32 km/h), for at least 10 seconds, and
within 15 minutes from when the vehicle is stationary.
You will have one minute to match the rst tire/wheel
position, and ve minutes overall, to match all four
tire/wheel positions. If it takes longer than one minute,
to match the rst tire and wheel, or more than ve
minutes to match all four tire/wheel positions the
matching process stops and you will need to start over.
The TPM matching process is outlined below:
1. Set the parking brake.
2. Press the push-button ignition switch to OFF/ACC.
3. Using the Keyless Access transmitter, lock and
unlock the vehicle’s doors.4. Press the lock and unlock buttons, at the same
time, on the Keyless Access transmitter. A single
horn chirp will sound, indicating that the TPM
system is ready, and the sensor matching process
can begin.
5. Start with the left (driver’s side) front tire.
6. Remove the valve cap from the valve stem.
Activate the TPM sensor by increasing or
decreasing the tire’s air pressure for ve seconds,
or until a horn chirp sounds. The horn chirp,
which may take up to 30 seconds, conrms that the
sensor identication code has been matched to
this tire position. To decrease the tire’s air-pressure
use the pointed end of the valve cap, a pencil-style
air pressure gauge, or a key.
7. Proceed to the right (passenger’s side) front tire,
and repeat the procedure in Step 6.
8. Proceed to the right (passenger’s side) rear tire,
and repeat the procedure in Step 6.
9. Proceed to the left (driver’s side) rear tire, and
repeat the procedure in Step 6.
10. After hearing the conrming double horn chirp, for
the left rear tire, exit the matching process by
pressing the push-button ignition switch to
OFF/ACC.
5-64

The underhood fuse block is located in the front of the
engine compartment on the passenger’s side of the
vehicle. SeeEngine Compartment Overview on
page 5-12for more information on location, and removal
procedure for the front compartment underhood sights
shields.
To access the fuses, push in the tabs located on each
side of the fuse block cover. Then, lift the cover off.
Fuses Usage
BLOWER Blower Motor
R REAR Passenger’s Side Rear Fuse Block
I/P OUTLET Front Auxiliary Outlet
CCP Climate Control, Headlamp Leveling
PRE 02/CAM Oxygen Sensor, CAM Phasers
ENG W/H Engine W/H
R REAR Passenger’s Side Rear Fuse Block
WPR SW Wiper/Washer Switch
BODY W/H Body W/H
FOG LAMP Fog Lamps
OUTLET Rear Auxiliary Outlet
EVEN COILSEven Ignition Coils, Even Fuel
Injectors
L REAR Left Rear Fuse Block
WPR MOD Wiper Module
POST 02 Oxygen Sensor
Fuses Usage
COMP CLTCH Air Conditioner Compressor Clutch
STARTER Starter Solenoid
ABS Anti-Lock Brake Pump
L REAR Driver’s Side Rear Fuse Block
BODY W/H Body W/H
RAIN SSRRain Sensor, Headlamp Washer,
Tire Pressure Monitor
CCP Climate Control
SMT BM-OPT Smart Beam Relay (Option)
EXT LIGHTSLow Beam Relay, High Beam Relay,
Park Lamp Relay
VOLT CHECK Instrument Panel Module
ECM/TCMEngine Control Module,
Transmission Control Module,
Easy Key Module, Instrument
Panel Cluster
SPARE Spare
SPARE Spare
LT PARK Left Park Lamp, Left Taillamp
LIC DIMMINGLicense Plate, Instrument Panel
Dimming
IPM ALDLInstrument Panel Module Assembly
Line Data Link Connector
HUDHeads-Up Display, Column Lock
Module
5-97

Fuses Usage
V8 ECM V8 ECM, Evap Solenoid
ABS Anti-Lock Brake Controller
STR RLY Starter Relay
WASH
NOZ/AQSHeated Washer Nozzles, Air Quality
Sensor™
ODD COILSOdd Ignition Coils, Odd Fuel
Injectors
TCM IPCTransmission, Instrument Panel,
Engine Control
SPARE Spare
MAF Mass Air Flow Sensor
HIGH FAN Cooling Fan - High Speed
LOW FAN Cooling Fan - Low Speed
RT PARK Right Park Lamp, Right Taillamp
HORN Horn
LT HI BEAM Left Headlamp High Beam
LT LOW BEAM Left Headlamp Low Beam
RT LOW BEAM Right Headlamp Low Beam
RT HI BEAM Right Headlamp High Beam
HFV6 ECMHigh Feature V6 Engine Control
ModuleRelays Usage
HDLP WASH
RELAY
JUMPER -OPTHeadlamp Washer
STARTER
RELAY MINIStarter
SPARE Spare
FOG LAMP
RELAY MICROFog Lamps
CMP CLU
RELAY MICROA/C Compressor Clutch
BLOWER
RELAY MINIFront Blower Motor
POWERTRAIN
RELAY MICROEngine Controls
RUN/CRANK
RELAY MICROIgnition 1
LOW SPEED
FAN RELAY
MINICooling Fan Low Speed
ACCESSORY
RELAY MINIIgnition 3
PARK LAMP
RELAY MICROParking Lamps
5-98