2008 CADILLAC CTS check engine light

If the check engine light comes on to indicate that there
is an OBD II problem and service is required.
Malfunctions often are indicated by the system before
any problem is apparent. Heeding the light can prevent
more serious damage to your vehicle. This system
assists your service technician in correctly diagnosing
any malfunction.
Notice:If you keep driving your vehicle with
this light on, after a while, the emission controls
might not work as well, your vehicle’s fuel economy
might not be as good, and the engine might not
run as smoothly. This could lead to costly repairs
that might not be covered by your warranty.
Notice:Modications made to the engine,
transmission, exhaust, intake, or fuel system of
your vehicle or the replacement of the original tires
with other than those of the same Tire Performance
Criteria (TPC) can affect your vehicle’s emission
controls and can cause this light to come on.
Modications to these systems could lead to costly
repairs not covered by your warranty. This could
also result in a failure to pass a required Emission
Inspection/Maintenance test. SeeAccessories
and Modifications on page 5-4.This light comes on during a malfunction in one of
two ways:
Light Flashing:A misre condition has been detected.
A misre increases vehicle emissions and could
damage the emission control system on your vehicle.
Diagnosis and service might be required.
The following can prevent more serious damage to the
vehicle:
Reduce vehicle speed.
Avoid hard accelerations.
Avoid steep uphill grades.
If towing a trailer, reduce the amount of cargo being
hauled as soon as it is possible.
If the light continues to ash, when it is safe to do so,
stop the vehicle. Find a safe place to park the vehicle.
Turn the key off, wait at least 10 seconds, and restart
the engine. If the light is still ashing, follow the previous
steps and see your dealer/retailer for service as soon
as possible.
Light On Steady:An emission control system
malfunction has been detected on the vehicle.
Diagnosis and service might be required.
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An emission system malfunction might be corrected by
doing the following:
Make sure the fuel cap is fully installed. SeeFilling
the Tank on page 5-9. The diagnostic system can
determine if the fuel cap has been left off or
improperly installed. A loose or missing fuel cap
allows fuel to evaporate into the atmosphere.
A few driving trips with the cap properly installed
should turn the light off.
If the vehicle has been driven through a deep
puddle of water, the vehicle’s electrical system
might be wet. The condition is usually corrected
when the electrical system dries out. A few driving
trips should turn the light off.
Make sure to fuel the vehicle with quality fuel.
Poor fuel quality causes the engine not to run
as efficiently as designed and may cause: stalling
after start-up, stalling when the vehicle is changed
into gear, misring, hesitation on acceleration,
or stumbling on acceleration. These conditions
might go away once the engine is warmed up.
If one or more of these conditions occurs, change
the fuel brand used. It will require at least one
full tank of the proper fuel to turn the light off.
SeeGasoline Octane on page 5-7.
If none of the above have made the light turn off,
your dealer/retailer can check the vehicle.The dealer/retailer has the proper test equipment
and diagnostic tools to x any mechanical or
electrical problems that might have developed.
Emissions Inspection and Maintenance
Programs
Some state/provincial and local governments have or
might begin programs to inspect the emission control
equipment on the vehicle. Failure to pass this inspection
could prevent getting a vehicle registration.
Here are some things to know to help the vehicle pass
an inspection:
The vehicle will not pass this inspection if the check
engine light is on or not working properly.
The vehicle will not pass this inspection if the OBD
(on-board diagnostic) system determines that critical
emission control systems have not been completely
diagnosed by the system. The vehicle would be
considered not ready for inspection. This can happen
if the battery has recently been replaced or if the
battery has run down. The diagnostic system is
designed to evaluate critical emission control
systems during normal driving. This can take several
days of routine driving. If this has been done and the
vehicle still does not pass the inspection for lack of
OBD system readiness, your dealer/retailer can
prepare the vehicle for inspection.
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Oil Pressure Light
Your vehicle may have this
feature.
If the vehicle has an oil problem, this light may stay on
after the engine is started, or come on while you are
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 will come 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 will sound 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. You or others could be burned. Check the
oil as soon as possible and have the vehicle
serviced.
Notice:Lack of proper engine oil maintenance may
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.
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Engine Oil Pressure Gage
Your vehicle may have an engine oil pressure gage.
It shows the engine oil pressure in psi (pounds per
square inch) when the engine is running. Canadian
vehicles indicate pressure in kPa (kilopascals).
Oil pressure may vary with engine speed, outside
temperature and oil viscosity, but if readings are outside
the normal operating range, the oil pressure light will
come on. SeeOil Pressure Light on page 3-44for more
information.A reading outside the normal operating range may be
caused by a dangerously low oil level or some other
problem causing low oil pressure. Check your oil as
soon as possible. See Oil pressure Low Stop Engine
underDIC Warnings and Messages on page 3-56
andEngine Oil on page 5-16.
{CAUTION:
Do not keep driving if the oil pressure is low.
The engine can become so hot that it catches
re. You or others could be burned. Check the
oil as soon as possible and have the vehicle
serviced.
Notice:Lack of proper engine oil maintenance
may 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. United States
Canada
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Automatic Light Control Off
This message displays when the automatic headlamps
are turned off.
Automatic Light Control On
This message displays when the automatic headlamps
are turned on.
Battery Saver Active
This message displays when the system detects that
the battery voltage is dropping below expected levels.
The battery saver system starts reducing certain
features of the vehicle that you may 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 vehicle information button until Battery Voltage is
displayed.
Battery Volts Low
This message displays when the electrical system is
charging less than 10 volts or the battery has been
drained.
If this message appears immediately after starting the
engine, it is possible that the generator can still recharge
the battery. The battery should recharge while driving,
but may take a few hours to do so. Consider using
an auxiliary charger to boost the battery after returning
home or to a nal destination. Make sure you follow
the manufacturer’s instructions.
If this message appears while driving or after starting
your vehicle and stays on, have it checked immediately
to determine the cause of this problem.
To help the generator recharge the battery quickly,
you can reduce the load on the electrical system
by turning off the accessories.
The normal battery voltage range is 11.5 to 15.5 volts.
You can monitor battery voltage on the DIC by pressing
the vehicle information button until Battery Voltage is
displayed.
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Calibrating Drive In Circles
This message displays when calibrating the compass.
Drive the vehicle in circles at less than 5 mph (8 km/h)
to complete the calibration. SeeDIC Compass on
page 3-53for more information.
Calibration Complete
This message displays when the compass calibration is
complete. SeeDIC Compass on page 3-53for more
information.
Change Engine Oil Soon
When this message displays, it means that service is
required for your vehicle. See your dealer/retailer.
SeeEngine Oil on page 5-16andScheduled
Maintenance on page 6-4for more information.
When you reset the Change Engine Oil Soon message
by clearing it from the display, you still must reset
the engine oil life system separately. For more
information on resetting the engine oil life system,
seeEngine Oil Life System on page 5-19.
Check Tire Pressure
This message displays when the pressure in one or
more of the vehicle’s tires needs to be checked.
This message also displays Left Front, Right Front,
Left Rear, or Right Rear to indicate which tire needs
to be checked. You can receive more than one tire
pressure message at a time. To read the other
messages that may have been sent at the same time,
press the set/reset button. If a tire pressure message
appears on the DIC, stop as soon as you can. Have the
tire pressures checked and set to those shown on the
Tire Loading Information label. SeeTires on page 5-58,
Loading the Vehicle on page 4-22, andInflation - Tire
Pressure on page 5-66. The DIC display also shows the
tire pressure values. SeeDIC Operation and Displays
on page 3-48. If the tire pressure is low, the low tire
pressure warning light comes on. SeeTire Pressure
Light on page 3-41.
Cruise Set To XXX MPH (km/h)
This message displays whenever the cruise control is set.
SeeCruise Control on page 3-14for more information.
Driver Door Open
This message displays when the driver door is not closed
completely. Make sure that the door is closed completely.
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Electronic Key Not Detected Restart
Allowed
If your vehicle has the keyless access system, this
message displays when the keyless access transmitter
is not detected inside the vehicle while you are trying
to turn the ignition off. Your vehicle may be near a strong
radio antenna signal causing the keyless access
system to be jammed. The vehicle will remain in
ACC/ACCESSORY until the vehicle is turned off or is
started, or ve minutes has expired. If you turn the
ignition off and you cannot nd the keyless access
transmitter, you will not be able to restart the vehicle.
The keyless access transmitter needs to be inside of the
vehicle in order for the vehicle to start. SeeStarting
the Engine on page 2-35for more information.
Engine Hot A/C (Air Conditioning) Off
This message displays when the engine coolant
becomes hotter than the normal operating temperature.
SeeEngine Coolant Temperature Gage on page 3-40.
To avoid added strain on a hot engine, the air
conditioning compressor automatically turns off. When
the coolant temperature returns to normal, the air
conditioning compressor turns back on. You can
continue to drive your vehicle.
If this message continues to appear, have the system
repaired by your dealer/retailer as soon as possible
to avoid damage to the engine.
Engine Oil Low Add Oil
If your vehicle has an oil level sensor, this message
displays if the oil level in the vehicle is low. Check the oil
level and correct it as necessary. You may need to let
the vehicle cool or warm up and cycle the ignition
to be sure this message clears.
This message clears itself after 10 seconds, until the
next ignition cycle. SeeEngine Oil on page 5-16
for additional information.
Engine Overheated Idle Engine
Notice:If you drive your vehicle while the engine is
overheating, severe engine damage may occur.
If an overheat warning appears on the instrument
panel cluster and/or DIC, stop the vehicle as soon as
possible. Do not increase the engine speed above
normal idling speed. SeeEngine Overheating
on page 5-31for more information.
This message displays when the engine coolant
temperature is too hot. Stop and allow the vehicle to
idle until it cools down. SeeEngine Coolant
Temperature Warning Light on page 3-40.
SeeOverheated Engine Protection Operating Mode on
page 5-33for information on driving to a safe place
in an emergency.
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StabiliTrak Off
This message displays when you turn off StabiliTrak,
or when the stability control has been automatically
disabled. The TCS/StabiliTrak warning light on
the instrument panel cluster also comes on.
To realize the full benets of the stability enhancement
system, you should normally leave StabiliTrak on.
To turn the StabiliTrak system on or off, seeStabiliTrak
®
System on page 4-8.
There are several conditions that can cause this message
to appear.
One condition is overheating, which could occur if
StabiliTrak®activates continuously for an extended
period of time.
The message also displays if the brake system
warning light is on. SeeBrake System Warning Light
on page 3-38.
The message could display if the stability system
takes longer than usual to complete its diagnostic
checks due to driving conditions.
The message displays if an engine or vehicle related
problem has been detected and the vehicle needs
service. See your dealer/retailer.
The message turns off as soon as the conditions that
caused the message to be displayed are no longer
present.
Start Aborted By Theft Deterrent
This message displays if there is a communication
problem between the keyless access system and the
vehicle. The vehicle cannot be started when this
message displays. See your dealer/retailer for service.
Theft Attempted
This message displays if the theft-deterrent system has
detected a break-in attempt while you were away
from your vehicle. SeeTheft-Deterrent System on
page 2-28for more information.
Tighten Gas Cap
This message displays when the fuel cap has not been
fully tightened. Recheck the fuel cap to ensure that it
is on and tightened properly.
Tire Learning Active
This message displays when the Tire Pressure Monitor
System (TPMS) is re-learning the tire positions on
your vehicle. The tire positions must be re-learned after
rotating the tires or after replacing a tire or sensor.
SeeTire Inspection and Rotation on page 5-74,
Tire Pressure Monitor System on page 5-69, and
Inflation - Tire Pressure on page 5-66for more
information.
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