2010 CADILLAC DTS check engine

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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Service. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-3Accessories and Modifications . . . . . . . . . . . . . . . . . . . . . . . . . .6-3California Proposition 65 Warning . . . . . . . . . . . . . . . . . . . . .6-4California Perchlorate Materials Requirements . . . . .6-4Doing Your Own Service Work . . . . . . . . . . . . . . . . . . . . . . . . .6-4Adding Equipment to the Outsideof the Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-5
Fuel. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-5Gasoline Octane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-5Gasoline Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-6California Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-6Additives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-6Fuels in Foreign Countries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-7Filling the Tank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-8Filling a Portable Fuel Container . . . . . . . . . . . . . . . . . . . . .6-10
Checking Things Under the Hood. . . . . . . . . . . . . . . . . . . .6-10Hood Release . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-11Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . . . .6-12Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-13Engine Oil Life System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-16Engine Air Cleaner/Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-17Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . .6-19Cooling System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-22Engine Coolant . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-23Engine Overheating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-27
Overheated Engine ProtectionOperating Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-29Power Steering Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-30Windshield Washer Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-31Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-32Battery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-34Jump Starting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-36
Headlamp Aiming. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-40
Bulb Replacement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-43High Intensity Discharge (HID) Lighting . . . . . . . . . . . .6-43
Windshield Wiper Blade Replacement. . . . . . . . . . . . . .6-44
Tires. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-46Tire Sidewall Labeling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-47Tire Terminology and Definitions . . . . . . . . . . . . . . . . . . . . .6-52Inflation - Tire Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-54High-Speed Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-56Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . . . . . . .6-57Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . . .6-58Tire Inspection and Rotation . . . . . . . . . . . . . . . . . . . . . . . . . . .6-62When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . .6-64Buying New Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-64Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . .6-66Uniform Tire Quality Grading . . . . . . . . . . . . . . . . . . . . . . . . . .6-67Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . .6-68Wheel Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-68
Section 6 Service and Appearance Care
6-1

Keep a record with all parts receipts and list the mileageand the date of any service work performed. SeeMaintenance Record on page 7-12.
Adding Equipment to the Outside of
the Vehicle
Things added to the outside of the vehicle can affect theairflow around it. This can cause wind noise and canaffect fuel economy and windshield washer performance.Check with your dealer/retailer before adding equipmentto the outside of the vehicle.
Fuel
Use of the recommended fuel is an important part of theproper maintenance of this vehicle. To help keep theengine clean and maintain optimum vehicleperformance, we recommend the use of gasolineadvertised as TOP TIER Detergent Gasoline.
Look for the TOP TIER label on the fuel pump to ensuregasoline meets enhanced detergency standardsdeveloped by auto companies. A list of marketersproviding TOP TIER Detergent Gasoline can be foundat www.toptiergas.com.
Gasoline Octane
Use premium unleaded gasoline with a posted octanerating of 91 or higher. You can also use regularunleaded gasoline rated at 87 octane or higher, but thevehicle’s acceleration could be slightly reduced, anda slight audible knocking noise, commonly referred to asspark knock, might be heard. If the octane is lessthan 87, you might notice a heavy knocking noise whenyou drive.
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If this occurs, use a gasoline rated at 87 octane orhigher as soon as possible. Otherwise, you coulddamage the engine. If heavy knocking is heard whenusing gasoline rated at 87 octane or higher, the engineneeds service.
Gasoline Specifications
At a minimum, gasoline should meet ASTM specificationD 4814 in the United States or CAN/CGSB-3.5 or3.511 in Canada. Some gasolines contain anoctane-enhancing additive called methylcyclopentadienylmanganese tricarbonyl (MMT). We recommendagainst the use of gasolines containing MMT. SeeAdditives on page 6-6for additional information.
California Fuel
If the vehicle is certified to meet California EmissionsStandards, it is designed to operate on fuels thatmeet California specifications. See the underhoodemission control label. If this fuel is not availablein states adopting California emissions standards, thevehicle will operate satisfactorily on fuels meeting federalspecifications, but emission control system performancemight be affected. The malfunction indicator lampcould turn on and the vehicle might fail asmog-check test.
SeeMalfunction Indicator Lamp on page 4-57. If thisoccurs, return to your authorized dealer/retailer fordiagnosis. If it is determined that the condition is causedby the type of fuel used, repairs might not be coveredby the vehicle warranty.
Additives
To provide cleaner air, all gasolines in the United Statesare now required to contain additives that help preventengine and fuel system deposits from forming, allowingthe emission control system to work properly. In mostcases, nothing should have to be added to the fuel.However, some gasolines contain only the minimumamount of additive required to meet U.S. EnvironmentalProtection Agency regulations. To help keep fuel injectorsand intake valves clean, or if the vehicle experiencesproblems due to dirty injectors or valves, look for gasolinethat is advertised as TOP TIER Detergent Gasoline.
For customers who do not use TOP TIER DetergentGasoline regularly, one bottle of GM Fuel SystemTreatment PLUS, added to the fuel tank at everyengine oil change, can help clean deposits from fuelinjectors and intake valves. GM Fuel System TreatmentPLUS is the only gasoline additive recommended byGeneral Motors.
Also, your dealer/retailer has additives that will helpcorrect and prevent most deposit-related problems.
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Filling a Portable Fuel Container
{WARNING:
Never fill a portable fuel container while it is in the
vehicle. Static electricity discharge from the
container can ignite the fuel vapor. You can be
badly burned and the vehicle damaged if this
occurs. To help avoid injury to you and others:
•Dispense fuel only into approved containers.
•Do not fill a container while it is inside a
vehicle, in a vehicle’s trunk, pickup bed, or onany surface other than the ground.
•Bring the fill nozzle in contact with the inside
of the fill opening before operating the nozzle.Contact should be maintained until the fillingis complete.
•Do not smoke while pumping fuel.
•Do not use a cellular phone while
pumping fuel.
Checking Things Under
the Hood
{WARNING:
An electric fan under the hood can start up and
injure you even when the engine is not running.
Keep hands, clothing, and tools away from any
underhood electric fan.
{WARNING:
Things that burn can get on hot engine parts and
start a fire. These include liquids like fuel, oil,
coolant, brake fluid, windshield washer and other
fluids, and plastic or rubber. You or others could
be burned. Be careful not to drop or spill things
that will burn onto a hot engine.
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