2005 CADILLAC STS Electrical system

Seats and Restraint Systems........................... 1-1
Front Seats
............................................... 1-2
Rear Seats
............................................... 1-7
Safety Belts
.............................................. 1-8
Child Restraints
.......................................1-26
Airbag System
.........................................1-45
Restraint System Check
............................1-56
Features and Controls..................................... 2-1
Keys
........................................................ 2-2
Doors and Locks
......................................2-11
Windows
.................................................2-16
Theft-Deterrent Systems
............................2-19
Starting and Operating Your Vehicle
...........2-22
Mirrors
....................................................2-35
OnStar
®System
......................................2-39
HomeLink®Wireless Control System
...........2-41
Storage Areas
.........................................2-45
Sunroof
..................................................2-46
Vehicle Personalization
.............................2-47
Instrument Panel............................................. 3-1
Instrument Panel Overview
.......................... 3-4
Climate Controls
......................................3-50
Warning Lights, Gages, and Indicators
........3-60
Driver Information Center (DIC)
..................3-73
Audio System(s)
.......................................3-92Driving Your Vehicle....................................... 4-1
Your Driving, the Road, and Your Vehicle
..... 4-2
Towing
...................................................4-35
Service and Appearance Care.......................... 5-1
Service
..................................................... 5-3
Fuel
......................................................... 5-5
Checking Things Under the Hood
...............5-10
All-Wheel Drive
........................................5-42
Rear Axle
...............................................5-44
Front Axle
...............................................5-45
Headlamp Aiming
.....................................5-46
Bulb Replacement
....................................5-48
Windshield Replacement
...........................5-51
Windshield Wiper Blade Replacement
.........5-51
Tires
......................................................5-53
Appearance Care
.....................................5-85
Vehicle Identication
.................................5-94
Electrical System
......................................5-95
Capacities and Specications
...................5-106
Maintenance Schedule..................................... 6-1
Maintenance Schedule
................................ 6-2
Customer Assistance and Information.............. 7-1
Customer Assistance and Information
........... 7-2
Reporting Safety Defects
...........................7-10
Index................................................................ 1
2005 Cadillac STS Owner ManualM

{CAUTION:
Anyone who is up against, or very close to,
any airbag when it inates can be seriously
injured or killed. Airbags plus lap-shoulder
belts offer the best protection for adults, but
not for young children and infants. Neither the
vehicle’s safety belt system nor its airbag
system is designed for them. Young children
and infants need the protection that a child
restraint system can provide. Always secure
children properly in your vehicle. To read how,
seeOlder Children on page 1-26orInfants and
Young Children on page 1-28.There is an airbag
readiness light on the
instrument panel, which
shows the airbag symbol.
The system checks the airbag electrical system for
malfunctions. The light tells you if there is an electrical
problem. SeeAirbag Readiness Light on page 3-63
for more information.
1-47

Trunk
{CAUTION:
It can be dangerous to drive with the trunk lid
open because carbon monoxide (CO) gas can
come into your vehicle. You cannot see or
smell CO. It can cause unconsciousness and
even death. If you must drive with the trunk lid
open or if electrical wiring or other cable
connections must pass through the seal
between the body and the trunk lid:
Make sure all other windows are shut.
Turn the fan on your heating or cooling
system to its highest speed and select the
control setting that will force outside air
into your vehicle. See Climate Control
System in the Index.
If you have air outlets on or under the
instrument panel, open them all the way.
SeeEngine Exhaust on page 2-33.
Trunk Lid Release
There are several ways to release the trunk lid.
V(Trunk Lid Release):Press this button
located on the driver’s door. The vehicle must be in
PARK (P) or NEUTRAL (N) and the valet mode
turned off. To disable valet mode, seeValet Lockout
Switch on page 2-21.
Press the trunk lid release button on the keyless
access transmitter. SeeKeyless Access System
Operation on page 2-4. The vehicle must be
in PARK (P) or NEUTRAL (N) and the valet mode
turned off.
2-14

Starting the Engine
Move your shift lever to PARK (P) or NEUTRAL (N).
Your engine will not start in any other position — that is
a safety feature. To restart when you are already
moving, use NEUTRAL (N) only.
The keyless access transmitter must be in the vehicle
for the ignition to work.
Notice:Do not try to shift to PARK (P) if your
vehicle is moving. If you do, you could damage the
transmission. Shift to PARK (P) only when your
vehicle is stopped.
1. With your foot on the brake pedal, press the
START button. If no keyless access transmitter
is present, the DIC will display NO FOB
DETECTED. When the engine begins cranking, let
go of the button. The idle speed will go down as
your engine gets warm.
If the battery in the keyless access transmitter is
weak, the DIC will display FOB BATTERY
LOW. You can still drive the vehicle. See “Battery
Replacement” underKeyless Access System
Operation on page 2-4for more information.Notice:Holding the button in for longer than
15 seconds at a time will cause the vehicle’s battery
to be drained much sooner. This can also cause
damage to the starter motor. Wait 15 seconds
between each try to avoid draining your vehicle’s
battery or damaging the starter.
2. If the engine does not start and no DIC message is
displayed, wait 15 seconds before trying again.
Notice:Your engine is designed to work with the
electronics in your vehicle. If you add electrical
parts or accessories, you could change the way the
engine operates. Before adding electrical equipment,
check with your dealer. If you do not, your engine
might not perform properly.
Stopping Your Engine
Move the shift lever to PARK (P) and press the
OFF/ACCESSORY button. If the shifter is not in
PARK (P), the vehicle will go into accessory mode
and the DIC will display SHIFT TO PARK. Once the
shifter is moved to PARK (P), the vehicle will turn off.
If the keyless access transmitter is not detected
while going to off, the DIC will display NO FOB – OFF
OR RUN?.
SeeDIC Warnings and Messages on page 3-78for
more information.
2-24

Entry Lighting
The entry lighting system turns on the reading and
dome lamps and the backlighting to the exterior lamp
control when a door is opened or if you press the remote
keyless entry transmitter unlock button. If activated by
the transmitter, the lighting will remain active for
about 25 seconds. The entry lighting system uses the
light sensor; it must be dark outside in order for the
lamps to turn on. The lamps turn off about 25 seconds
after the last door is closed. They will dim to off if
the ignition is on, or immediately deactivate if the power
locks are activated.
Parade Dimming
This feature prohibits dimming of the instrument panel
displays and backlighting during daylight hours when the
key is in the ignition and the headlamps are on. This
feature operates with the light sensor and is fully
automatic. When the light sensor reads darkness outside
and the parking lamps are active, the instrument
panel displays can be adjusted by turning the instrument
panel brightness knob. SeeInstrument Panel Brightness
on page 3-41for additional information.
Reading Lamps
The reading lamps are located on the overhead console.
These lamps come on automatically when any door is
opened.
For manual operation, press the button next to each
lamp to turn it on. Press it again to turn the lamp off.
If the reading lamps are left on, they automatically shut
off 10 minutes after the ignition has been turned off.
Battery Load Management
The battery load management feature is designed to
monitor the vehicle’s electrical load and determine when
the battery is in a heavy discharge condition. During
times of high electrical loading, the engine may idle at
a higher revolutions per minute (rpm) setting than normal
to make sure the battery charges. High electrical
loads may occur when several of the following are on:
headlamps, high beams, fog lamps, rear window
defogger, the climate control fan at high speeds, heated
seats and engine cooling fans.
3-42

Airbag Readiness Light
There is an airbag readiness light on the instrument
panel, which shows the airbag symbol. The system
checks the airbag’s electrical system for malfunctions.
The light tells you if there is an electrical problem.
The system check includes the airbag sensors, the
airbag modules, the wiring and the diagnostic module.
For more information on the airbag system, see
Airbag System on page 1-45.
This light will come on
when you start your
vehicle, and it will ash
for a few seconds.
Then the light should go
out. This means the
system is ready.
If the airbag readiness light stays on after you start
the vehicle or comes on when you are driving,
your airbag system may not work properly. Have your
vehicle serviced right away.{CAUTION:
If the airbag readiness light stays on after you
start your vehicle, it means the airbag system
may not be working properly. The airbags in
your vehicle may not inate in a crash, or they
could even inate without a crash. To help
avoid injury to yourself or others, have your
vehicle serviced right away if the airbag
readiness light stays on after you start your
vehicle.
The airbag readiness light should ash for a few
seconds when you turn the vehicle on. If the light does
not come on then, have it xed so it will be ready to
warn you if there is a problem.
If there is a problem with the airbag system in your
vehicle, the Service airbag message will appear on the
DIC display. SeeDIC Warnings and Messages on
page 3-78for more information.
3-63

If the Light Is Flashing
The following may prevent more serious damage to
your vehicle:
Reducing vehicle speed
Avoiding hard accelerations
Avoiding steep uphill grades
If the light stops ashing and remains on steady, see
“If the Light Is On Steady” following.
If the light continues to ash, when it is safe to do so,
stop the vehicle. Find a safe place to park your vehicle.
Turn the engine off, wait at least 10 seconds and
restart the engine. If the light remains on steady, see
“If the Light Is On Steady” following. If the light is
still ashing, follow the previous steps, and see your
dealer for service as soon as possible.
If the Light Is On Steady
You also may be able to correct the emission system
malfunction by considering the following:
Did you recently put fuel into your vehicle?
If so, reinstall the fuel cap, making sure to fully install
the cap. SeeFilling the Tank on page 5-8. The
diagnostic system can determine if the fuel cap has
been left off or improperly installed. A loose or missing
fuel cap will allow fuel to evaporate into the atmosphere.
A few driving trips with the cap properly installed
should turn the light off.Did you just drive through a deep puddle of water?
If so, your electrical system may be wet. The condition
will usually be corrected when the electrical system
dries out. A few driving trips should turn the light off.
Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel. See
Gasoline Octane on page 5-5. Poor fuel quality will
cause your engine not to run as efficiently as designed.
You may notice this as stalling after start-up, stalling
when you put the vehicle into gear, misring, hesitation
on acceleration, or stumbling on acceleration. (These
conditions may go away once the engine is warmed up.)
This will be detected by the system and cause the
light to turn on.
If you experience one or more of these conditions,
change the fuel brand you use. It will require at least
one full tank of the proper fuel to turn the light off.
If none of the above steps have made the light turn off,
your dealer can check the vehicle. Your dealer has
the proper test equipment and diagnostic tools to x
any mechanical or electrical problems that may
have developed.
3-69

AUTOMATIC LIGHTS OFF
This message will display when the automatic
headlamps are turned off. SeeHeadlamps on page 3-33
for more information.
AUTOMATIC LIGHTS ON
This message will display when the automatic
headlamps are turned on. SeeHeadlamps on page 3-33
for more information.
BATTERY NOT CHARGING SERVICE
CHARGING SYS (System)
This symbol appears with
the BATTERY NOT
CHARGING SERVICE
CHARGING SYS
message.
This message will display when a problem with the
charging system has been detected. Have your vehicle
serviced by your GM dealer.
BATTERY SAVER ACTIVE
This message will display when the system detects that
the battery voltage is dropping beyond a reasonable
level. The battery saver system will start reducing certain
features of the vehicle that you may not be able to
notice. At the point that the features are disabled, this
message is displayed. It means that the vehicle is trying
to save the charge in the battery.
Turn off all unnecessary accessories to allow the battery
to recharge.
The normal battery voltage range is 11.5 to 15.5 volts.
You can monitor battery voltage on the DIC by pressing
the information button until you nd BATTERY VOLTS.
BATTERY VOLTAGE HIGH
This symbol appears with
the BATTERY VOLTAGE
HIGH message.
This message will display when the electrical charging
system is overcharging the battery. When the system
detects that the battery voltage is above approximately
16 volts, this message will be displayed.
3-79