ECU CADILLAC STS 2009 1.G Service Manual

Oil Pressure Light
For vehicles with an oil
pressure light, if there
is a problem with the oil,
the light may stay on
after the engine is started,
or comes on while
driving.
This light indicates that oil is not going through the
engine quickly enough to keep it lubricated. The engine
could be low on oil or could have some other oil problem.
Have it xed right away.
The oil light could also come on in the following
situations:
The light comes on briey when the ignition is
turned on to show that it is working properly.
If it does not come on with the ignition on, there
may be a problem with the fuse or bulb. Have
it xed right away.
Sometimes when the engine is idling at a stop, a
chime sounds and the light may blink on and off.
This is normal.
{CAUTION:
Do not keep driving if the oil pressure is low.
The engine can become so hot that it catches re.
Someone could be burned. Check the oil as soon
as possible and have the vehicle serviced.
Notice:Lack of proper engine oil maintenance
can damage the engine. The repairs would not be
covered by the vehicle warranty. Always follow
the maintenance schedule in this manual for
changing engine oil.
Security Light
For information regarding
this light and the vehicle’s
security system, see
Theft-Deterrent System
on page 2-21.
3-69

SERVICE STEERING SYS (System)
Your vehicle has a speed variable assist steering
system. Your All-Wheel Drive (AWD) vehicle may have
the Active Steering with Enhanced StabiliTrak option.
See “Active Steering” underSteering on page 4-12.
This message displays if a problem is detected with
the speed variable assist steering system or the Active
Steering system. When this message is displayed, you
may notice that the effort required to steer the vehicle
increases or feels heavier, but you will still be able to
steer the vehicle. SeeSteering on page 4-12for more
information. Have the steering system inspected by
your dealer/retailer as soon as possible.
If the SERVICE STEERING SYS message appears
because the Active Steering system needs service,
normal power steering is still operational. However,
compared to Active Steering, normal power steering
requires a larger degree of steering wheel input at
low vehicle speeds and a smaller degree of steering
wheel input at high vehicle speeds. The center position
of the steering wheel may be different. You may
continue to drive your vehicle with normal power
steering, but have the steering system inspected
by your dealer/retailer as soon as possible.
If the Active Steering system needs service, the system
may be operating in the Stability Secure Mode and
the STABILITY SECURE MODE message will display.
SeeEnhanced StabiliTrak
®on page 4-6.When certain steering faults are present, the vehicle
speed may be limited. If vehicle speed is limited,
the SPEED LIMITED TO XXX message will display.
See “Active Steering” underSteering on page 4-12.
SERVICE SUSPENSION SYS (System)
This message displays when the suspension system
is not operating properly. Have your vehicle serviced
by your dealer/retailer.
If your All-Wheel Drive (AWD) vehicle has the Active
Steering with Enhanced StabiliTrak option and the
suspension system needs service, the Enhanced
StabiliTrak system may be operating in the Stability
Secure Mode and the STABILITY SECURE MODE
message will display. SeeEnhanced StabiliTrak
®
on page 4-6.
SERVICE TIRE MONITOR
This message displays if a part on the Tire Pressure
Monitor System (TPMS) is not working properly. The tire
pressure light also ashes and then remains on during
the same ignition cycle. SeeTire Pressure Light on
page 3-65. Several conditions may cause this message
to appear. SeeTire Pressure Monitor Operation on
page 5-68for more information. If the warning comes on
and stays on, there may be a problem with the TPMS.
See your dealer/retailer.
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STABILITY COMPETITIVE MODE
If your All-Wheel Drive (AWD) vehicle has the Active
Steering with Enhanced StabiliTrak option, this message
displays when the Competitive Mode for stability control
has been turned on using the TC (traction control) button.
SeeEnhanced StabiliTrak
®on page 4-6for more
information. When the Enhanced StabiliTrak Competitive
Mode has been activated, traction control operates in
competitive mode and cannot be turned off. Also, the
Active Steering and the Magnetic Ride Control systems
operate in the Performance Mode. For more information,
see “Active Steering and Magnetic Ride Control” in the
Index in the Navigation manual.
STABILITY SECURE MODE
If your All-Wheel Drive (AWD) vehicle has the Active
Steering with Enhanced StabiliTrak option, this message
displays when the stability control system is in the
secure mode. Stability Secure Mode is set automatically
when certain system faults or vehicle conditions are
detected. When the Stability Secure Mode is activated,
the stability control system will not respond to driver
requests to change the stability mode until the next
ignition cycle or until the vehicle condition or fault
is returned to normal. SeeEnhanced StabiliTrak
®
on page 4-6for more information.
STABILITY SYS (System) ACTIVE
This message displays any time the StabiliTrak system
or Enhanced StabiliTrak system is actively assisting
with directional control of the vehicle. Slippery road
conditions may exist when this message is displayed,
so adjust your driving accordingly. This message
may stay on for a few seconds after StabiliTrak
stops assisting with directional control of the vehicle.
SeeStabiliTrak
®System on page 4-6orEnhanced
StabiliTrak®on page 4-6for more information.
STABILITY SYS (System) NOT READY
This message displays if the StabiliTrak system is
not ready. Two conditions may cause this message
to display:
The vehicle needs to be driven in a straight line
until the sensors are centered. Once the sensors
are centered, the StabiliTrak system is ready
and the STABILITY SYS READY message displays.
The system needs to warm up. This may occur
when rst starting your vehicle and driving away
during cold winter weather. This is normal.
To acknowledge this message, press the
reset button.
The StabiliTrak performance is affected until the
STABILITY SYS READY message is displayed in the
DIC. SeeStabiliTrak
®System on page 4-6for more
information.
3-93

STABILITY SYS (System) OFF
This message displays any time StabiliTrak or
Enhanced StabiliTrak is turned off using the TC (traction
control) on/off button. SeeTraction Control System (TCS)
on page 4-10and “Enhanced StabiliTrak and Traction
Control Mode Selection” underEnhanced StabiliTrak
®on
page 4-6for more information. When this message has
been displayed, StabiliTrak or Enhanced StabiliTrak is
no longer available to assist with directional control of the
vehicle. Adjust your driving accordingly. SeeStabiliTrak
®
System on page 4-6orEnhanced StabiliTrak®on
page 4-6for more information.
STABILITY SYS (System) READY
This message displays any time StabiliTrak is turned
back on using the TC (traction control) on/off button.
SeeTraction Control System (TCS) on page 4-10
for more information. When this message has been
displayed, StabiliTrak is ready to assist with directional
control of the vehicle, if needed. SeeStabiliTrak
®
System on page 4-6for more information.
STABILITY TOURING MODE
If your All-Wheel Drive (AWD) vehicle has the Active
Steering with Enhanced StabiliTrak option, this message
displays when the Stability Touring Mode is re-activated
by using the traction control button after:
Driving in the Stability Competitive Mode.
The stability control system is turned off by
the driver.
This message may also display after exiting STABILITY
SECURE MODE when certain system faults or vehicle
conditions have been cleared. SeeEnhanced
StabiliTrak
®on page 4-6.
STARTING DISABLED THEFT
PROBLEM
This message displays when incorrect conditions exist
within the theft-deterrent system. See your dealer/retailer
for service.
STARTING DISABLED THROTTLE
PROBLEM
This message displays when your vehicle’s throttle
system is not functioning properly. Have your vehicle
serviced by your dealer/retailer.
3-94

Channel Unavail:This previously assigned channel
is no longer assigned. Tune to another station.
If this station was one of the presets, choose another
station for that preset button.
No Artist Info:No artist information is available at this
time on this channel. The system is working properly.
No Title Info:No song title information is available
at this time on this channel. The system is working
properly.
No CAT Info:No category information is available
at this time on this channel. The system is working
properly.
No Information:No text or informational messages are
available at this time on this channel. The system is
working properly.
CAT Not Found:There are no channels available for
the selected category. The system is working properly.XM Theftlocked:The XM™ receiver in your vehicle
could have previously been in another vehicle.
For security purposes, XM™ receivers cannot be
swapped between vehicles. If this message is received
after having your vehicle serviced, check with your
dealer/retailer.
XM Radio ID:If tuned to channel 0, this message
alternates with the XM™ Radio 8 digit radio ID label.
This label is needed to activate the service.
Unknown:If this message is received when tuned to
channel 0, there could be a receiver fault. Consult
with your dealer/retailer.
Check XM Receivr:If this message does not clear
within a short period of time, the receiver could have a
fault. Consult with your dealer/retailer.
XM Not Available:If this message does not clear
within a short period of time, the receiver could have
a fault. Consult with your dealer/retailer.
3-115

If there is a problem detected with Enhanced StabiliTrak,
the SERVICE STABILITY SYS message will be
displayed on the DIC. SeeDIC Warnings and Messages
on page 3-79. When this message is displayed, the
system is not operating. Driving should be adjusted
accordingly.
When certain faults or vehicle conditions are detected,
the Stability control will automatically go into a secure
mode and the STABILITY SECURE MODE message will
be displayed on the DIC. When the Stability Secure
Mode is activated, the stability control system will
not respond to driver requests to change the stability
mode until the next ignition cycle or until the vehicle
condition or fault is returned to normal. When the
Stability Secure Mode is activated, other messages
may be displayed, such as SERVICE STEERING SYS,
SERVICE SUSPENSION SYS or CHECK TIRE
PRESSURE on the DIC. When the Stability Secure
Mode is activated, a larger degree of steering wheel
input at low vehicle speeds and a smaller degree
of steering wheel input at high vehicle speeds may be
required. Stability Secure Mode will be activated if
a compact spare tire is being used. SeeDIC Warnings
and Messages on page 3-79andCompact Spare
Tire on page 5-114.Persistent operation of the vehicle in the STABILITY
SECURE MODE may be an indication that the vehicle
needs to be serviced by your dealer/retailer.
When certain faults are present, the vehicle’s speed
may be limited and the SPEED LIMITED TO XXX
message will be displayed on the DIC. SeeDIC
Warnings and Messages on page 3-79. When the
vehicle’s speed is limited, other messages may
be displayed, such as SERVICE STABILITY SYS,
SERVICE STEERING SYS or SERVICE SUSPENSION
SYS on the DIC. Have the vehicle serviced by your
dealer/retailer.
Enhanced StabiliTrak and Traction Control
Mode Selection
Enhanced StabiliTrak can be operated in Touring Mode
or Competitive Mode. It can also be turned off. The
TC button is used to change stability control modes
(Touring, Competitive or Off) as well as to turn traction
control on or off. SeeTraction Control System (TCS)
on page 4-10. The following information describes
the operation of the TC button for changing Traction
Control and Stability Control Modes.
4-8

{CAUTION:
Things you put inside the vehicle can strike
and injure people in a sudden stop or turn,
or in a crash.
Put things in the trunk of your vehicle.
In a trunk, put them as far forward as you
can. Try to spread the weight evenly.
Never stack heavier things, like
suitcases, inside the vehicle so that some
of them are above the tops of the seats.
Do not leave an unsecured child restraint
in the vehicle.
When you carry something inside the
vehicle, secure it whenever you can.
Do not leave a seat folded down unless
you need to.
Towing
Towing Your Vehicle
Consult your dealer/retailer or a professional towing
service if the disabled vehicle needs to be towed.
SeeRoadside Service on page 7-7.
To tow the vehicle behind another vehicle for
recreational purposes (such as behind a motorhome),
see Recreational Vehicle Towing following.
Recreational Vehicle Towing
Recreational vehicle towing means towing the vehicle
behind another vehicle – such as behind a motorhome.
The two most common types of recreational vehicle
towing are known as “dinghy towing” — towing the
vehicle with all four wheels on the ground, and “dolly
towing” — towing the vehicle with two wheels on the
ground and two wheels up on a device known as
a “dolly”.
4-29

Rear-wheel drive vehicles can be towed using a dolly.
To tow the vehicle using a dolly, follow these steps:
1. Attach the dolly to the tow vehicle following the dolly
manufacturer’s instructions.
2. Drive the rear wheels onto the dolly.
3. Firmly set the parking brake. SeeParking Brake on
page 2-33.
4. Put the transmission in P (Park).
5. Secure the vehicle to the dolly following the
manufacturer’s instructions.
6. Use an adequate clamping device designed for
towing to ensure that the front wheels are locked
into the straight position.
7. Turn the ignition to LOCK/OFF.
Dolly Towing (STS-V)
Notice:Dolly towing or dinghy towing the vehicle
may cause damage because of reduced ground
clearance. Always put the vehicle on a atbed truck.
The STS-V can only be towed on a at-bed truck or
trailer.
Dolly Towing (All-Wheel-Drive Vehicles)
Notice:Towing an all-wheel-drive vehicle with all
four wheels on the ground, or even with only two of
its wheels on the ground, will damage drivetrain
components. Do not tow an all-wheel-drive vehicle
with any of its wheels on the ground.
All-Wheel Drive (AWD) vehicles can only be towed on a
at-bed truck or trailer.
Towing a Trailer (Vehicles Without
Heavy Duty Cooling)
Vehicles without heavy duty cooling are neither designed
nor intended to tow a trailer.
4-31

Pulling A Trailer
Here are some important points:
Do not tow a trailer at all during the rst 500 miles
(800 km) the new vehicle is driven. The engine,
axle or other parts could be damaged.
Then, during the rst 500 miles (800 km) that a
trailer is towed, do not drive over 50 mph (80 km/h)
and do not make starts at full throttle. This helps
the engine and other parts of the vehicle wear in at
the heavier loads.
Vehicles can tow in D (Drive). Shift the transmission
to a lower gear if the transmission shifts too often
under heavy loads and/or hilly conditions.
Obey speed limit restrictions when towing a trailer.
Do not drive faster than the maximum posted
speed for trailers, or no more than 55 mph
(90 km/h), to save wear on the vehicle’s parts.
Three important considerations have to do with weight:
The weight of the trailer.
The weight of the trailer tongue.
The total weight on the vehicle’s tires.
Weight of the Trailer
How heavy can a trailer safely be?
It should never weigh more than 1,000 lbs (450 kg).
But even that can be too heavy.
It depends on how the rig is used. For example, speed,
altitude, road grades, outside temperature and how much
the vehicle is used to pull a trailer are all important. It can
depend on any special equipment on the vehicle, and
the amount of tongue weight the vehicle can carry.
See “Weight of the Trailer Tongue” later in this section
for more information.
Maximum trailer weight is calculated assuming only the
driver is in the tow vehicle and it has all the required
trailering equipment. The weight of additional optional
equipment, passengers and cargo in the tow vehicle
must be subtracted from the maximum trailer weight.
Ask your dealer/retailer for our trailering information
or advice, or write us at our Customer Assistance
Offices. SeeCustomer Assistance Offices on page 7-6
for more information.
4-33

Driving with a Trailer
Towing a trailer requires a certain amount of experience.
Get to know the rig before setting out for the open
road. Get acquainted with the feel of handling and
braking with the added weight of the trailer. And always
keep in mind that the vehicle you are driving is now
longer and not as responsive as the vehicle is by itself.
Before starting, check all trailer hitch parts and
attachments, safety chains, electrical connectors, lamps,
tires and mirror adjustments. If the trailer has electric
brakes, start the vehicle and trailer moving and then
apply the trailer brake controller by hand to be sure the
brakes are working. This checks the electrical connection
at the same time.
During the trip, check occasionally to be sure that the
load is secure, and that the lamps and any trailer brakes
are still working.
Following Distance
Stay at least twice as far behind the vehicle ahead as
you would when driving the vehicle without a trailer.
This can help to avoid situations that require heavy
braking and sudden turns.
Passing
More passing distance is needed when towing a trailer.
Because the rig is longer, it is necessary to go much
farther beyond the passed vehicle before returning to
the lane.
Backing Up
Hold the bottom of the steering wheel with one hand.
Then, to move the trailer to the left, move that hand
to the left. To move the trailer to the right, move your
hand to the right. Always back up slowly and, if possible,
have someone guide you.
Making Turns
Notice:Making very sharp turns while trailering
could cause the trailer to come in contact with the
vehicle. The vehicle could be damaged. Avoid
making very sharp turns while trailering.
When turning with a trailer, make wider turns than
normal. Do this so the trailer will not strike soft
shoulders, curbs, road signs, trees or other objects.
Avoid jerky or sudden maneuvers. Signal well in
advance.
4-36