2009 CADILLAC STS Owners Manual

Electrical System
Add-On Electrical Equipment
Notice:Do not add anything electrical to the
vehicle unless you check with your dealer/retailer
rst. Some electrical equipment can damage
the vehicle and the damage would not be covered
by the vehicle’s warranty. Some add-on electrical
equipment can keep other components from
working as they should.
Add-on equipment can drain the vehicle battery, even if
the vehicle is not operating.
The vehicle has an airbag system. Before attempting to
add anything electrical to the vehicle, seeServicing
Your Airbag-Equipped Vehicle on page 1-64.
Headlamp Wiring
The headlamp wiring is protected by fuses in the fuse
block. An electrical overload will cause the lamps to turn
off. If this happens, have the headlamp wiring checked
right away.
Windshield Wiper Fuses
The windshield wiper motor is protected by an internal
circuit breaker. If the wiper motor overheats due to
heavy snow, the wipers will stop until the motor cools
and will then restart.
Power Windows and Other Power
Options
Circuit breakers in the fuse block protect the power
windows and other power accessories. When the current
load is too heavy, the circuit breaker opens and closes,
protecting the circuit until the problem is xed or
goes away.
Fuses and Circuit Breakers
The wiring circuits in the vehicle are protected from
short circuits by a combination of fuses, circuit breakers
and fusible thermal links. This greatly reduces the
chance of res caused by electrical problems.
Look at the silver-colored band inside the fuse. If the
band is broken or melted, replace the fuse. Be sure you
replace a bad fuse with a new one of the identical
size and rating.
Fuses of the same amperage can be temporarily
borrowed from another fuse location, if a fuse goes out.
Replace the fuse as soon as you can.
5-123

Underhood Fuse Block
5-124

The underhood fuse block is located in the front of
the engine compartment on the passenger 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.
Notice:Spilling liquid on any electrical components
on the vehicle may damage it. Always keep the
covers on any electrical component.
Fuses JCase Usage
ABS MTRABS Module - ABS Module -
Stabilitrak
AFS Active Front Steering
BLWR Blower Motor
FAN 1 Cooling Fan-Low Speed
FAN 2 Cooling Fan-High Speed
LPDB 1 Driver Side Rear Fuse Block
LPDB 2 Driver Side Rear Fuse Block
RPDB 1 Passenger Side Rear Fuse Block
RPDB 2 Passenger Side Rear Fuse Block
Fuses JCase Usage
SPARE Spare
SPARE Spare
STRTR Starter
Fuses Mini Usage
A/C CLTCH Air Conditioning Compressor Clutch
ABS ABS Module-Stabilitrak
ABS IGN Antilock Brake Controller
AUX OUTLET Rear Accessory Power Outlet
BRK VAC
PUMPBrake Vacuum Pump
CCP Climate Control Panel
CCP/RLY
COILSClimate Control Panel, Headlamp
Level Control, Active Cruise Control,
Relay Coils, Starter, Front Blower
ECM 1 Engine Control Module (ECM)
ECM/TCM
BATTECM, Transmission Control
Module (TCM)
ECM/TCM IGNECM, TCM, Instrument Panel
Cluster
5-125

Fuses Mini Usage
EKM/I/P MDLEasy Key Module (EKM), Instrument
Panel Module (I/P MDL)
EVEN COILSEven Ignition Coils, Even Fuel
Injectors
FOG LAMP Front Fog Lamps
FRT PWR
OUTLETFront Accessory Power Outlet
FUEL COOL Fuel Cooling
HORN Horn
HTD
WASH/AQSHeated Headlamp Washer,
Air Quality Sensor
HUDHeads-Up Display, Steering Column
Switch
I/BEAM IntelliBeam Relay
I/P MDL/ALDLInstrument Panel Module, Assembly
Line Data Link Connector
LIC DIMLicense Plate, Instrument Panel
Dimming
LT HI BEAM Driver Side High Beam Headlamp
LT LO BEAM Driver Side Low Beam Headlamp
LT PRKDriver Side Park Lamp/Driver Side
TaillampFuses Mini Usage
ODD COILSOdd Ignition Coils, Odd Fuel
Injectors
POST O2
SNSRPost Oxygen Sensor
PRE O2 SNSR Pre Oxygen Sensor, CAM Sensors
RAIN
SNSR/TPMRain Sensor, Relay Coil:
Headlamp Wash
RT HI BEAMPassenger Side High Beam
Headlamp
RT LO BEAMPassenger Side Low Beam
Headlamp
RT PRKPassenger Side Park Lamp,
Passenger Side Taillamp
SPARE Spare
SPARE Spare
SPARE Spare
SPARE Spare
SPARE Spare
SPARE Spare
SPARE Spare
5-126

Fuses Mini Usage
V/CHKInstrument Panel Module-Voltage
Check
WPR Wipe/Wash Module Assembly
WPR SW/VICS Rain Sensor, Wiper Switch
Relays Usage
A/C CMPRSR
CLTCHAir Conditioning Compressor Clutch
ACCYAccessory, Rain Sensor, Headlamp
Washer Relay Coil, Windshield
Wiper/Washer Module
BRK VAC
PUMPBrake Vacuum Pump
FAN S/P Cooling Fan Series/Parallel
FOG LAMP Fog Lamps
FRT BLWR Front Blower Motor
FUEL COOL Fuel Cooling Pump
HI BEAM High Beam Headlamp
HI FAN SPD Cooling Fan High Speed
HORN Horn
Relays Usage
LO FAN SPD Cooling Fan Low Speed
LOW BEAM
W/O HID/HIDLow Beam Headlamp, High Intensity
Discharge (HID)
PRK LAMPParking Lamps, Instrument Panel
Dimming, Rear License Plate Lamps
PWR/TRN Engine Controls
RUN CRNKHeated Washer Nozzle, Air Quality,
Antilock Brake System, Climate
Control Panel, TCM, ECM,
Instrument Panel Cluster
SPARE Spare
SPARE Spare
SPARE Spare
STRTR Starter
WPR HI Windshield Wiper High Speed
Circuit
BreakersUsage
HDLP WASHHeadlamp Washer Motor
(Circuit Breaker)
5-127

Rear Underseat Fuse Block
Removing the Rear Seat Cushion
Notice:If you touch the exposed wires with the
metal on the seat cushion, you could cause a
short that could damage the battery and or wires.
Avoid contact between the rear seat and the
fuse center whenever you remove or reinstall
the rear seat. Do not remove covers from any
of the covered parts, and do not store anything
under the seats.
To remove the rear seat cushion, do the following:
1. Pull up on the front of the cushion to release the
front hooks.
2. Pull the cushion up and out toward the front of the
vehicle.To reinstall the rear seat cushion, do the following:
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{CAUTION:
A safety belt that is not properly routed through
the seat cushion or is twisted will not provide the
protection needed in a crash. If the safety belt has
not been routed through the seat cushion at all, it
will not be there to work for the next passenger.
The person sitting in that position could be badly
injured. After reinstalling the seat cushion, always
check to be sure that the safety belts are properly
routed and are not twisted.
1. Buckle the center passenger position safety belt,
then route the safety belts through the proper slots
in the seat cushion. Do not let the safety belts
get twisted.
2. Slide the rear of the cushion up and under the
seatback so the rear-locating guides hook into
the wire loops on the back frame.
3. With the seat cushion lowered, push rearward and
then press down on the seat cushion until the
spring locks on both ends engage.4. Check to make sure the safety belts are properly
routed and that no portion of any safety belt is
trapped under the seat. Also make sure the
seat cushion is secured.Rear Underseat Fuse Block
There is a fuse block located under the rear seat on the
driver side and passenger side of the vehicle. The rear
seat cushion must be removed to access the fuse blocks.
See “Removing the Rear Seat Cushion” listed previously
in this section.
To access the fuses, push in the two tabs, then lift the
cover off.
5-129

The vehicle may not have all the fuses listed below.
Driver’s Side
Fuses Usage
AMP Amplier
INCLR PUMP Inner Cooler Pump (Option)
THEFT/SHFTTheft Sensors, Auto Shifter,
Power SounderFuses Usage
MRTD MDLMagnetic Ride Control Module
(Option)
REAR DR MDL Rear Door Modules
5-130