check engine CADILLAC DTS 2010 1.G User Guide

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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Hill and Mountain Roads
Driving on steep hills or through mountains is differentthan driving on flat or rolling terrain. Tips for drivingin these conditions include:
•Keep the vehicle serviced and in good shape.
•Check all fluid levels and brakes, tires, cooling
system, and transmission.
•Going down steep or long hills, shift to a
lower gear.
{WARNING:
If you do not shift down, the brakes could get so
hot that they would not work well. You would then
have poor braking or even none going down a hill.
You could crash. Shift down to let the engine
assist the brakes on a steep downhill slope.
{WARNING:
Coasting downhill in N (Neutral) or with the ignition
off is dangerous. The brakes will have to do all the
work of slowing down and they could get so hot
that they would not work well. You would then
have poor braking or even none going down a hill.
You could crash. Always have the engine running
and the vehicle in gear when going downhill.
•Stay in your own lane. Do not swing wide or cut
across the center of the road. Drive at speedsthat let you stay in your own lane.
•Top of hills: Be alert — something could be in your
lane (stalled car, accident).
•Pay attention to special road signs (falling rocks
area, winding roads, long grades, passing orno-passing zones) and take appropriate action.
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Blizzard Conditions
Being stuck in snow can be in a serious situation.Stay with the vehicle unless there is help nearby.If possible, use theRoadside Service on page 8-7.To get help and keep everyone in the vehicle safe:
•Turn on theHazard Warning Flashers on page 4-3.
•Tie a red cloth to an outside mirror.
{WARNING:
Snow can trap engine exhaust under the vehicle.
This may cause exhaust gases to get inside.
Engine exhaust contains carbon monoxide (CO)
which cannot be seen or smelled. It can cause
unconsciousness and even death.
If the vehicle is stuck in the snow:
•Clear away snow from around the base of
your vehicle, especially any that is blockingthe exhaust pipe.
•Check again from time to time to be sure
snow does not collect there.
WARNING: (Continued)
WARNING: (Continued)
•Open a window about 5 cm (two inches) on
the side of the vehicle that is away from thewind to bring in fresh air.
•Fully open the air outlets on or under the
instrument panel.
•Adjust the Climate Control system to a setting
that circulates the air inside the vehicle andset the fan speed to the highest setting.See Climate Control System in the Index.
For more information about carbon monoxide, seeEngine Exhaust on page 3-34.
Snow can trap exhaust gases under your vehicle.This can cause deadly CO (carbon monoxide) gasto get inside. CO could overcome you and kill you.You cannot see it or smell it, so you might notknow it is in your vehicle. Clear away snow fromaround the base of your vehicle, especially anythat is blocking the exhaust.
To save fuel, run the engine for only short periods asneeded to warm the vehicle and then shut the engine offand close the window most of the way to save heat.
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Hitches
It is important to have the correct hitch equipment.Crosswinds, large trucks going by and rough roads are afew reasons why the right hitch is needed. Here are somerules to follow:
•The rear bumper on the vehicle is not intended for
hitches. Do not attach rental hitches or otherbumper-type hitches to it. Use only a frame-mountedhitch that does not attach to the bumper.
•Will any holes be made in the body of the vehicle
when the trailer hitch is installed? If there are, thenbe sure to seal the holes later when the hitch isremoved. If the holes are not sealed, dirt, water, anddeadly carbon monoxide (CO) from the exhaust canget into the vehicle. SeeEngine Exhaust onpage 3-34for more information.
Safety Chains
Always attach chains between the vehicle and thetrailer. Cross the safety chains under the tongue of thetrailer to help prevent the tongue from contactingthe road if it becomes separated from the hitch.Instructions about safety chains may be provided by thehitch manufacturer or by the trailer manufacturer.Follow the manufacturer’s recommendation for attachingsafety chains and do not attach them to the bumper.Always leave just enough slack so the rig can turn.Never allow safety chains to drag on the ground.
Trailer Brakes
Because the vehicle has StabiliTrak®, do not tap intothe vehicle’s hydraulic brake system. If you do,both brake systems will not work well, or at all.
Be sure to read and follow the instructions for the trailerbrakes so they are installed, adjusted and maintainedproperly.
Driving with a Trailer
Towing a trailer requires a certain amount of experience.Get to know the rig before setting out for the openroad. Get acquainted with the feel of handling andbraking with the added weight of the trailer. And alwayskeep in mind that the vehicle you are driving is nowlonger and not as responsive as the vehicle is by itself.
Before starting, check all trailer hitch parts andattachments, safety chains, electrical connectors, lamps,tires and mirror adjustments. If the trailer has electricbrakes, start the vehicle and trailer moving andthen apply the trailer brake controller by hand to be surethe brakes are working. This checks the electricalconnection at the same time.
During the trip, check occasionally to be sure that theload is secure, and that the lamps and any trailer brakesare still working.
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Leaving After Parking on a Hill
1. Apply and hold the brake pedal while you:
•start the engine,
•shift into a gear, and
•release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and storethe chocks.
Maintenance When Trailer Towing
The vehicle needs service more often when pulling atrailer. SeeScheduled Maintenance on page 7-3for moreinformation. Things that are especially important in traileroperation are automatic transmission fluid, engine oil,belts, cooling system and brake system. It is a good ideato inspect these before and during the trip.
Check periodically to see that all hitch nuts and boltsare tight.
Engine Cooling When Trailer Towing
The cooling system may temporarily overheat duringsevere operating conditions. SeeEngine Overheating onpage 6-27.
Changing a Tire When Trailer Towing
If the vehicle gets a flat tire while towing a trailer,be sure to secure the trailer and disconnect it from thevehicle before changing the tire.
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