2010 CADILLAC DTS check engine

Charging System Light
This light comes on brieflywhen the ignition key isturned to START, butthe engine is not running,as a check to show itis working.
If it does not, have the vehicle serviced by yourdealer/retailer.
The light should go out once the engine starts. If it stayson, or comes on while driving, there could be aproblem with the charging system. A charging systemmessage in the Driver Information Center (DIC) can alsoappear. SeeDIC Warnings and Messages on page 4-67for more information. This light could indicate thatthere are problems with a generator drive belt, or thatthere is an electrical problem. Have it checked rightaway. If the vehicle must be driven a short distance withthe light on, turn off accessories, such as the radioand air conditioner.
Brake System Warning Light
The vehicle’s hydraulic brake system is divided intotwo parts. If one part is not working, the other part canstill work and stop the vehicle. For good brakingboth parts need to be working.
If the warning light comes on, there is a brake problem.Have the brake system inspected right away.
This light comes on briefly when the engine is turnedon. If it does not come on then, have it fixed so it will beready to warn if there is a problem.
When the ignition is on, the brake system warning lightalso comes on when the parking brake is set. Thelight will stay on if the parking brake does not releasefully. If it stays on after the parking brake is fullyreleased, it means there is a brake problem.
United StatesCanada
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Engine Coolant Temperature Gage
This gage shows theengine coolanttemperature.
It indicates when the engine has warmed up and if thecooling system is operating properly. If the gagepointer moves into the shaded area, the engine coolantis too hot and the engine coolant temperature warninglight comes on. SeeEngine Overheating on page 6-27for more information.
Tire Pressure Light
For vehicles with a tire pressure monitoring system, thislight comes on briefly when the engine is started. Itprovides information about tire pressures and the TirePressure Monitoring System.
When the Light is On Steady
This indicates that one or more of the tires aresignificantly underinflated.
A tire pressure message in the Driver InformationCenter (DIC), can accompany the light. SeeDriverInformation Center (DIC) on page 4-61for moreinformation. Stop and check the tires as soon as it issafe to do so. If underinflated, inflate to the properpressure. SeeInflation - Tire Pressure on page 6-54formore information.
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When the Light Flashes First and Then is
On Steady
This indicates that there may be a problem with the TirePressure Monitor System. The light flashes for abouta minute and stays on steady for the remainder ofthe ignition cycle. This sequence repeats with everyignition cycle. SeeTire Pressure Monitor Operation onpage 6-58for more information.
Malfunction Indicator Lamp
Check Engine Light
A computer system called OBD II (On-BoardDiagnostics-Second Generation) monitors operation ofthe fuel, ignition, and emission control systems. Itensures that emissions are at acceptable levels for thelife of the vehicle, helping to produce a cleanerenvironment.
This light should come onwhen the ignition is on, butthe engine is not running,as a check to show itis working. If it does not,have the vehicle servicedby your dealer/retailer.
If the check engine light comes on and stays on, whilethe engine is running, this indicates that there is anOBD II problem and service is required.
Malfunctions often are indicated by the system beforeany problem is apparent. Being aware of the lightcan prevent more serious damage to the vehicle. Thissystem assists the service technician in correctlydiagnosing any malfunction.
Notice:If the vehicle is continually driven with thislight on, after a while, the emission controlsmight not work as well, the vehicle’s fuel economymight not be as good, and the engine might notrun as smoothly. This could lead to costly repairsthat might not be covered by the vehicle warranty.
Notice:Modifications made to the engine,transmission, exhaust, intake, or fuel system of thevehicle or the replacement of the original tireswith other than those of the same Tire PerformanceCriteria (TPC) can affect the vehicle’s emissioncontrols and can cause this light to come on.Modifications to these systems could lead to costlyrepairs not covered by the vehicle warranty. Thiscould also result in a failure to pass a requiredEmission Inspection/Maintenance test. SeeAccessories and Modifications on page 6-3.
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This light comes on during a malfunction in one oftwo ways:
Light Flashing:A misfire condition has been detected.A misfire increases vehicle emissions and coulddamage the emission control system on the vehicle.Diagnosis and service might be required.
To 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 flash, when it is safe to do so, stopthe vehicle. Find a safe place to park the vehicle. Turn thekey off, wait at least 10 seconds, and restart the engine. Ifthe light is still flashing, follow the previous steps and seeyour dealer/retailer for service as soon as possible.
Light On Steady:An emission control systemmalfunction has been detected on the vehicle. Diagnosisand service might be required.
An emission system malfunction might be corrected bydoing the following:
•Make sure the fuel cap is fully installed. SeeFilling
the Tank on page 6-8. The diagnostic system candetermine if the fuel cap has been left off or
improperly installed. A loose or missing fuel capallows fuel to evaporate into the atmosphere. A fewdriving trips with the cap properly installed shouldturn the light off.
•If the vehicle has been driven through a deep
puddle of water, the vehicle’s electrical systemmight be wet. The condition is usually correctedwhen the electrical system dries out. A few drivingtrips should turn the light off.
•Make sure to fuel the vehicle with quality fuel.
Poor fuel quality causes the engine not to runas efficiently as designed and can cause: stallingafter start-up, stalling when the vehicle is changedinto gear, misfiring, hesitation on acceleration,or stumbling on acceleration. These conditionsmight go away once the engine is warmed up.
If one or more of these conditions occurs, changethe fuel brand used. It will require at least onefull tank of the proper fuel to turn the light off.
SeeGasoline Octane on page 6-5.
If none of the above have made the light turn off, yourdealer/retailer can check the vehicle. The dealer/retailerhas the proper test equipment and diagnostic tools tofix any mechanical or electrical problems that mighthave developed.
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Emissions Inspection and Maintenance
Programs
Some state/provincial and local governments have ormight begin programs to inspect the emission controlequipment on the vehicle. Failure to pass this inspectioncould prevent getting a vehicle registration.
Here are some things to know to help the vehicle passan inspection:
•The vehicle will not pass this inspection if the check
engine light is on with the engine running, or if thekey is in ON/RUN and the light is not on.
•The vehicle will not pass this inspection if the
OBD II (on-board diagnostic) system determinesthat critical emission control systems have not beencompletely diagnosed by the system. The vehiclewould be considered not ready for inspection.This can happen if the battery has recently beenreplaced or if the battery has run down. Thediagnostic system is designed to evaluate criticalemission control systems during normal driving.This can take several days of routine driving. If thishas been done and the vehicle still does notpass the inspection for lack of OBD II systemreadiness, your dealer/retailer can preparethe vehicle for inspection.
Oil Pressure Light
{WARNING:
Do not keep driving if the oil pressure is low. The
engine can become so hot that it catches fire.
Someone could be burned. Check the oil as soon
as possible and have the vehicle serviced.
Notice:Lack of proper engine oil maintenance candamage the engine. The repairs would not becovered by the vehicle warranty. Always follow themaintenance schedule in this manual for changingengine oil.
This light comes on briefly while starting the engine.If it does not, have the vehicle serviced by yourdealer/retailer. If the system is working normally theindicator light then goes off.
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AUTOMATIC LIGHT CONTROL ON
This message displays when the automatic headlampsare turned on. SeeExterior Lamps on page 4-25formore information.
BATTERY SAVER ACTIVE
This message displays when the system detects thatthe battery voltage is dropping beyond a reasonablelevel. The battery saver system starts reducing certainfeatures of the vehicle that you may be able to notice.At the point that the features are disabled, this messageis displayed. It means that the vehicle is trying tosave the charge in the battery.
Turn off all unnecessary accessories to allow the batteryto recharge.
The normal battery voltage range is 11.5 to 15.5 volts.You can monitor battery voltage on the DriverInformation Center (DIC) by pressing the trip/fuel buttonuntil BATTERY VOLTAGE is displayed.
CHANGE ENGINE OIL SOON
This message displays when service is required for yourvehicle. See your dealer/retailer. SeeEngine Oil onpage 6-13andScheduled Maintenance on page 7-3formore information.
When you reset the CHANGE ENGINE OIL SOONmessage by clearing it from the display, you still mustreset the engine oil life system separately. For moreinformation on resetting the engine oil life system, seeEngine Oil Life System on page 6-16.
CHECK TIRE PRESSURE or ADD AIR
TO TIRE
On vehicles with the Tire Pressure Monitor System(TPMS), this message displays when the pressure inone or more of the vehicle’s tires is low. This messagealso displays LEFT FRONT, RIGHT FRONT, LEFTREAR, or RIGHT REAR to indicate which tire needs tobe checked. The low tire pressure warning light willalso come on. SeeTire Pressure Light on page 4-56.If a tire pressure message appears on the DIC, stop assoon as you can. Have the tire pressures checkedand set to those shown on the Tire Loading Informationlabel. SeeTires on page 6-46,Loading the Vehicleon page 5-18, andInflation - Tire Pressure onpage 6-54. You can receive more than one tire pressuremessage at a time. To read the other messages thatmay have been sent at the same time, press theset/reset button. The DIC also shows the tire pressurevalues. SeeDIC Operation and Displays on page 4-62.
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Keeping pace with the traffic and allowing realisticfollowing distances eliminates a lot of unnecessarybraking. That means better braking and longer brake life.
If the engine ever stops while the vehicle is being driven,brake normally but do not pump the brakes. If the brakesare pumped, the pedal could get harder to push down.If the engine stops, there will still be some power brakeassist but it will be used when the brake is applied. Oncethe power assist is used up, it can take longer to stop andthe brake pedal will be harder to push.
Adding non-dealer/non-retailer accessories can affectvehicle performance. SeeAccessories and Modificationson page 6-3.
Antilock Brake System (ABS)
This vehicle has the Antilock Brake System (ABS), anadvanced electronic braking system that helps prevent abraking skid.
When the engine is started and the vehicle begins todrive away, ABS checks itself. A momentary motoror clicking noise might be heard while this test is goingon, and it might even be noticed that the brake pedalmoves a little. This is normal.
If there is a problem withABS, this warning lightstays on. SeeAntilockBrake System (ABS)Warning Light onpage 4-53.
Let us say the road is wet and you are driving safely.Suddenly, an animal jumps out in front of you. You slamon the brakes and continue braking. Here is whathappens with ABS:
A computer senses that the wheels are slowing down.If one of the wheels is about to stop rolling, the computerwill separately work the brakes at each front wheeland at both rear wheels.
ABS can change the brake pressure to each wheel, asrequired, faster than any driver could. This can helpthe driver steer around the obstacle while braking hard.
As the brakes are applied, the computer keepsreceiving updates on wheel speed and controls brakingpressure accordingly.
Remember: ABS does not change the time needed to geta foot up to the brake pedal or always decrease stoppingdistance. If you get too close to the vehicle in front of you,there will not be enough time to apply the brakes if thatvehicle suddenly slows or stops. Always leave enoughroom up ahead to stop, even with ABS.
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Before Leaving on a Long Trip
To prepare your vehicle for a long trip, consider havingit serviced by your dealer/retailer before departing.
Things to check on your own include:
•Windshield Washer Fluid:Reservoir full? Windows
clean — inside and outside?
•Wiper Blades:In good shape?
•Fuel, Engine Oil, Other Fluids:All levels checked?
•Lamps:Do they all work and are lenses clean?
•Tires:Are treads good? Are tires inflated to
recommended pressure?
•Weather and Maps:Safe to travel?
Have up-to-date maps?
Highway Hypnosis
Always be alert and pay attention to your surroundingswhile driving. If you become tired or sleepy, find asafe place to park your vehicle and rest.
Other driving tips include:
•Keep the vehicle well ventilated.
•Keep interior temperature cool.
•Keep your eyes moving — scan the road ahead
and to the sides.
•Check the rearview mirror and vehicle
instruments often.
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