2010 CADILLAC DTS check engine light

Remote Vehicle Start
The remote vehicle starting feature allows you to startthe engine from outside of the vehicle. It also startsup the vehicle’s automatic climate control system. Whenthe remote start system is active, the climate controlsystem will heat and cool the inside of the vehicleaccording to the previous settings of the system beforeturning the vehicle off. The rear window defoggerwill be turned on by the climate control system when itis cold outside. If the vehicle has heated seats, theywill also turn on when it is cold outside. SeeHeated andVentilated Seats on page 2-5for additional information.Cooled seats are not activated during a remote start.Normal operation of the climate control system willreturn after the key is turned to ON/RUN. SeeDualClimate Control System on page 4-36.
Laws in some communities may restrict the use ofremote starters. For example, some laws may require aperson using remote start to have the vehicle in viewwhen doing so. Check local regulations for anyrequirements on remote starting of vehicles.
Do not use the remote start feature if your vehicle is lowon fuel. Your vehicle may run out of fuel.
If your vehicle has the remote start feature, the RKEtransmitter functions will have an increased rangeof operation. However, the range may be less while thevehicle is running.
There are other conditions which can affect theperformance of the transmitter, seeRemote KeylessEntry (RKE) System Operation on page 3-4foradditional information.
/(Remote Start):This button will be on the
RKE transmitter if you have remote start.
To start the vehicle using the remote start feature:
1. Aim the transmitter at the vehicle.
2. Press and release the transmitter’s lock button,then immediately press and hold the transmitter’sremote start button until the turn signal lightsflash or if the vehicle’s lights are not visible, pressand hold the remote start button for at leastfour seconds. Pressing the remote start buttonagain after the vehicle has started will turn off theignition.
When the vehicle starts, the parking lamps will turnon and remain on while the vehicle is running.The vehicle’s doors will be locked.
3. If it is the first remote start since the vehicle has beendriven, repeat these steps, while the engine is stillrunning, to extend the engine running time by10 minutes. Remote start can be extended one time.
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PASS-Key®III+ Electronic
Immobilizer
SeeRadio Frequency Statement on page 8-20forinformation regarding Part 15 of the FederalCommunications Commission (FCC) Rules andRSS-210/211 of Industry and Science Canada.
PASS-Key®III+ Electronic
Immobilizer Operation
Your vehicle has PASS-Key®III+ (PersonalizedAutomotive Security System) theft-deterrent system.PASS-Key®III+ is a passive theft-deterrent system.
The system is automatically armed when the keyis removed from the ignition.
The system is automatically disarmed when the key isturned to ON/RUN, ACC/ACCESSORY or STARTfrom the LOCK/OFF position.
You do not have to manually arm or disarm the system.
The security light will come on if there is a problemwith arming or disarming the theft-deterrent system.
When the PASS-Key®III+ system senses that someoneis using the wrong key, it prevents the vehicle fromstarting. Anyone using a trial-and-error method to startthe vehicle will be discouraged because of the highnumber of electrical key codes.
If the engine does not start and the security light comeson when trying to start the vehicle, there may be aproblem with your theft-deterrent system. Turnthe ignition off and try again.
If the engine still does not start, and the key appears tobe undamaged, try another ignition key. At this time,you may also want to check the fuse, seeFusesand Circuit Breakers on page 6-101. If the engine stilldoes not start with the other key, your vehicle needsservice. If your vehicle does start, the first key may befaulty. See your dealer/retailer who can service thePASS-Key®III+ to have a new key made. In anemergency, contact Roadside Assistance.
It is possible for the PASS-Key®III+ decoder to “learn”the transponder value of a new or replacement key.Up to 10 keys may be programmed for the vehicle.The following procedure is for programming additionalkeys only. If all the currently programmed keys arelost or do not operate, you must see your dealer/retaileror a locksmith who can service PASS-Key®III+ tohave keys made and programmed to the system.
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Warning Lights, Gages, and
Indicators
Warning lights and gages can signal that something iswrong before it becomes serious enough to causean expensive repair or replacement. Paying attention tothe warning lights and gages could prevent injury.
Warning lights come on when there might be or there isa problem with one of the vehicle’s functions. Somewarning lights come on briefly when the engine is startedto indicate they are working.
Gages can indicate when there might be or there is aproblem with one of the vehicle’s functions. Often gagesand warning lights work together to indicate a problemwith the vehicle.
When one of the warning lights comes on and stays onwhile driving, or when one of the gages shows therecould be a problem, check the section that explains whatto do. Follow this manual’s advice. Waiting to dorepairs can be costly and even dangerous.
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Airbag Readiness Light
The system checks the airbag’s electrical system forpossible malfunctions. If the light stays on it indicatesthere is an electrical problem. The system checkincludes the airbag sensor, the pretensioners, the airbagmodules, the wiring and the crash sensing anddiagnostic module. For more information on the airbagsystem, seeAirbag System on page 2-58.
The airbag readiness lightflashes for a few secondswhen the engine isstarted. If the light doesnot come on then, have itfixed immediately.
{WARNING:
If the airbag readiness light stays on after the
vehicle is started or comes on while driving, it
means the airbag system might not be working
properly. The airbags in the vehicle might not
inflate in a crash, or they could even inflate
without a crash. To help avoid injury, have the
vehicle serviced right away.
If there is a problem with the airbag system, an airbagDriver Information Center (DIC) message can also comeon. SeeDIC Warnings and Messages on page 4-67for more information.
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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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