2010 CADILLAC DTS check engine

A.Underhood Fuse Block on page 6-101.
B. Remote Positive (+) Terminal. SeeJump Starting onpage 6-36.
C. Windshield Washer Fluid Reservoir. See “AddingWasher Fluid” underWindshield Washer Fluidon page 6-31.
D. Engine Coolant Surge Tank and Pressure Cap.SeeEngine Coolant on page 6-23.
E. Remote Negative (!) Terminal. SeeJump Startingon page 6-36.
F.Power Steering Fluid on page 6-30.
G. Engine Oil Fill Cap. See “When to Add Engine Oil”underEngine Oil on page 6-13.
H. Engine Oil Dipstick. See “Checking Engine Oil”underEngine Oil on page 6-13.
I. Brake Master Cylinder Reservoir. See “Brake Fluid”underBrakes on page 6-32.
J. Automatic Transmission Fluid Cap and Dipstick(Out of View). SeeAutomatic Transmission Fluid onpage 6-19.
K.Engine Air Cleaner/Filter on page 6-17.
Engine Oil
Checking Engine Oil
It is a good idea to check the engine oil level at eachfuel fill. In order to get an accurate reading, the oil mustbe warm and the vehicle must be on level ground.
The engine oil dipstick handle is a yellow loop. SeeEngine Compartment Overview on page 6-12forthe location of the engine oil dipstick.
1. Turn off the engine and give the oil several minutesto drain back into the oil pan. If this is not done, theoil dipstick might not show the actual level.
2. Pull out the dipstick and clean it with a paper towelor cloth, then push it back in all the way. Remove itagain, keeping the tip down, and check the level.
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Engine Oil Additives / Engine Oil
Flushes
Do not add anything to the oil. The recommended oilswith the starburst symbol that meet GM standards are allthat is needed for good performance and engineprotection.
Engine oil system flushes are not recommended andcould cause engine damage not covered by the vehiclewarranty.
Engine Oil Life System
When to Change Engine Oil
This vehicle has a computer system that indicates whento change the engine oil and filter. This is based onengine revolutions and engine temperature, and not onmileage. Based on driving conditions, the mileage atwhich an oil change is indicated can vary considerably.For the oil life system to work properly, the systemmust be reset every time the oil is changed.
When the system has calculated that oil life has beendiminished, it indicates that an oil change is necessary.A CHANGE ENGINE OIL SOON message in theDriver Information Center (DIC) comes on. Change theoil as soon as possible within the next 600 miles(1 000 km). It is possible that, if driving under the bestconditions, the oil life system might not indicate thatan oil change is necessary for over a year. However, theengine oil and filter must be changed at least once ayear and at this time the system must be reset.Your dealer/retailer has trained people who will performthis work using genuine parts and reset the system.It is also important to check the oil regularly and keep itat the proper level.
If the system is ever reset accidentally, the oil must bechanged at 3,000 miles (5 000 km) since the last oilchange. Remember to reset the oil life system wheneverthe oil is changed.
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{WARNING:
Operating the engine with the air cleaner/filter off
can cause you or others to be burned. The air
cleaner not only cleans the air; it helps to stop
flames if the engine backfires. If it is not there and
the engine backfires, you could be burned. Do not
drive with it off, and be careful working on the
engine with the air cleaner/filter off.
Notice:If the air cleaner/filter is off, a backfire cancause a damaging engine fire. And, dirt caneasily get into the engine, which will damage it.Always have the air cleaner/filter in place when youare driving.
Automatic Transmission Fluid
When to Check and Change Automatic
Transmission Fluid
A good time to check the automatic transmission fluidlevel is when the engine oil is changed.
Change the fluid and filter at the intervals listed inScheduled Maintenance on page 7-3, and be sure touse the transmission fluid listed inRecommended Fluidsand Lubricants on page 7-8.
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How to Check Automatic
Transmission Fluid
Because this operation can be a little difficult, you maychoose to have this done at the dealer/retailer servicedepartment.
If you do it yourself, be sure to follow all the instructionshere or you could get a false reading on the dipstick.
Notice:Too much or too little fluid can damageyour transmission. Too much can mean that someof the fluid could come out and fall on hot engineparts or exhaust system parts, starting a fire.Too little fluid could cause the transmission tooverheat. Be sure to get an accurate reading if youcheck your transmission fluid.
Wait at least 30 minutes before checking thetransmission fluid level if you have been driving:
•When outside temperatures are above 32°C (90°F).
•At high speed for quite a while.
•In heavy traffic — especially in hot weather.
•While pulling a trailer.
To get the right reading, the fluid should be atnormal operating temperature, which is 82°C to 93°C(180°F to 200°F).
Get the vehicle warmed up by driving about 24 km(15 miles) when outside temperatures are above10°C (50°F). If it is colder than 10°C (50°F), you mayhave to drive longer.
Checking the Fluid Level
Prepare the vehicle as follows:
1. Park the vehicle on a level place. Keep the enginerunning.
2. With the parking brake applied, place the shift leverin P (Park).
3. With your foot on the brake pedal, move the shiftlever through each gear range, pausing for aboutthree seconds in each range. Then, positionthe shift lever in P (Park).
4. Let the engine run at idle for three to five minutes.
Then, without shutting off the engine, follow these steps:
1. Locate the transmission fluid cap which is locatednext to the radiator hose and below the engine aircleaner/filter assembly on the driver side of thevehicle. The cap is marked TRANS FLUID.SeeEngine Compartment Overview on page 6-12for more information on location.
2. After removing the engine air cleaner/filter assemblyto reach the transmission fluid cap, turn the capcounterclockwise to remove. Pull out the dipstickand wipe it with a clean rag or paper towel.
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3. Push it back in all the way, wait three seconds, andthen pull it back out again.
4. Check both sides of the dipstick and readthe lower level. The fluid level must be in thecross-hatched area.
5. If the fluid level is in the acceptable range, push thedipstick back in all the way and turn the handleclockwise.
6. Reinstall the engine air cleaner/filter assembly.
How to Add Automatic Transmission
Fluid
Refer to the Maintenance Schedule to determine whatkind of transmission fluid to use. SeeRecommendedFluids and Lubricants on page 7-8.
If the fluid level is low, add only enough of the properfluid to bring the level into the cross-hatched area onthe dipstick.
1. Pull out the dipstick.
2. Using a long-neck funnel, add enough fluid at thedipstick hole to bring it to the proper level.
It does not take much fluid, generally less thanone pint (0.5 L). Do not overfill.
Notice:Use of the incorrect automatic transmissionfluid may damage the vehicle, and the damagesmay not be covered by the vehicle’s warranty.Always use the automatic transmission fluid listedinRecommended Fluids and Lubricants on page 7-8.
3. After adding fluid, recheck the fluid level asdescribed under “How to Check AutomaticTransmission Fluid,” earlier in this section.
4. When the correct fluid level is obtained, pushthe dipstick back in all the way and turn thehandle clockwise.
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{WARNING:
An electric engine cooling fan under the hood can
start up even when the engine is not running and
can cause injury. Keep hands, clothing, and tools
away from any underhood electric fan.
{WARNING:
Heater and radiator hoses, and other engine parts,
can be very hot. Do not touch them. If you do, you
can be burned.
Do not run the engine if there is a leak. If you run
the engine, it could lose all coolant. That could
cause an engine fire, and you could be burned.
Get any leak fixed before you drive the vehicle.
Notice:Using coolant other than DEX-COOL®cancause premature engine, heater core, or radiatorcorrosion. In addition, the engine coolant couldrequire changing sooner, at 50 000 km (30,000 miles)or 24 months, whichever occurs first. Any repairswould not be covered by the vehicle warranty.Always use DEX-COOL®(silicate-free) coolant inthe vehicle.
Engine Coolant
The cooling system in the vehicle is filled withDEX-COOL®engine coolant. This coolant is designedto remain in the vehicle for five years or 150,000 miles(240 000 km), whichever occurs first.
The following explains the cooling system and how tocheck and add coolant when it is low. If there is aproblem with engine overheating, seeEngineOverheating on page 6-27.
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Checking Coolant
The vehicle must be on a level surface when checkingthe coolant level.
Check to see if coolant is visible in the coolant recoverytank. If the coolant inside the coolant recovery tank isboiling, do not do anything else until it cools down.If coolant is visible but the coolant level is not ator above the FULL COLD mark, add a 50/50 mixture ofclean, drinkable water and DEX-COOL®coolant atthe coolant recovery tank, but be sure the coolingsystem is cool before this is done. SeeEngine Coolanton page 6-23for more information.
How to Add Coolant to the Surge Tank
{WARNING:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol and
it will burn if the engine parts are hot enough. Do
not spill coolant on a hot engine.
Notice:This vehicle has a specific coolant fillprocedure. Failure to follow this procedure couldcause the engine to overheat and be severelydamaged.
{WARNING:
An electric engine cooling fan under the hood can
start up even when the engine is not running and
can cause injury. Keep hands, clothing, and tools
away from any underhood electric fan.
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You may decide not to lift the hood when this warningappears, but instead get service help right away.SeeRoadside Service on page 8-7.
If you do decide to lift the hood, make sure the vehicleis parked on a level surface.
Then check to see if the engine cooling fans arerunning. If the engine is overheating, both fans shouldbe running. If they are not, do not continue to runthe engine and have the vehicle serviced.
Notice:Engine damage from running the enginewithout coolant is not covered by the warranty.
Notice:If the engine catches fire while driving withno coolant, the vehicle can be badly damaged.The costly repairs would not be covered bythe vehicle warranty. SeeOverheated EngineProtection Operating Mode on page 6-29forinformation on driving to a safe place in anemergency.
If Steam Is Coming From The Engine
Compartment
{WARNING:
Steam from an overheated engine can burn you
badly, even if you just open the hood. Stay away
from the engine if you see or hear steam coming
from it. Turn it off and get everyone away from the
vehicle until it cools down. Wait until there is no sign
of steam or coolant before you open the hood.
If you keep driving when the vehicles engine is
overheated, the liquids in it can catch fire. You or
others could be badly burned. Stop the engine if it
overheats, and get out of the vehicle until the
engine is cool.
SeeOverheated Engine Protection Operating Mode
on page 6-29for information on driving to a safe
place in an emergency.
6-28