2010 CADILLAC DTS cooling

Reading Lamps
The reading lamps are located on the overhead consoleon the headliner and in the rear door opening. Theselamps come on automatically when any door is openedand it is dark outside.
For manual operation, press the button to turn them on.Press it again to turn them off.
If the reading lamps are left on, they automatically shutoff 10 minutes after the ignition has been turned off.
Footwell Lamps
For vehicles with footwell lamps, they are located underthe instrument panel and at the rear of the frontseats. These lamps provide soft light to the front andrear floor areas. They dim with the instrument panelcluster lights.
Footwell lighting brightness can be adjusted with theinstrument panel brightness control located belowthe exterior lamps control. SeeInstrument PanelBrightness on page 4-31. The footwell lights will turn offbefore the instrument panel lights are at their lowestlevel of brightness.
Battery Load Management
This feature monitors the vehicle’s electrical load anddetermines when the battery is in a heavy dischargecondition. During times of high electrical loading,the engine may idle at a higher revolutions per minute(rpm) setting than normal to make sure the batterycharges. High electrical loads may occur when severalof the following are on: headlamps, high beams, foglamps, rear window defogger, the climate control fan athigh speeds, heated seats and engine cooling fans.
If the battery continues to discharge, even withthe engine idling at a higher rpm setting, some electricalloads will automatically be reduced. When this occurs,the rear window defogger may take slightly longerto clear the glass, the heated seats may not get as warmas they usually do and the climate control fan may cutback to a lower speed. For more battery savinginformation, see “Battery Saver Active Message” underDIC Warnings and Messages on page 4-67.
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Electric Power Management
The vehicle has Electric Power Management (EPM) thatestimates the battery’s temperature and state ofcharge. It then adjusts the voltage for best performanceand extended life of the battery.
When the battery’s state of charge is low, the voltage israised slightly to quickly bring the charge back up.When the state of charge is high, the voltage is loweredslightly to prevent overcharging. If the vehicle has avoltmeter gage or a voltage display on the DriverInformation Center (DIC), you may see the voltage moveup or down. This is normal. If there is a problem, analert will be displayed.
The battery can be discharged at idle if the electricalloads are very high. This is true for all vehicles. This isbecause the generator (alternator) may not bespinning fast enough at idle to produce all the powerthat is needed for very high electrical loads.
A high electrical load occurs when several of thefollowing are on, such as: headlamps, high beams, foglamps, rear window defogger, climate control fan athigh speed, heated seats, engine cooling fans, trailerloads, and loads plugged into accessory power outlets.
EPM works to prevent excessive discharge of thebattery. It does this by balancing the generator’s outputand the vehicle’s electrical needs. It can increase
engine idle speed to generate more power, wheneverneeded. It can temporarily reduce the power demands ofsome accessories.
Normally, these actions occur in steps or levels, withoutbeing noticeable. In rare cases at the highest levelsof corrective action, this action may be noticeable to thedriver. If so, a Driver Information Center (DIC)message might be displayed, such as BATTERYSAVER ACTIVE, BATTERY VOLTAGE LOW, orLOW BATTERY. If this message is displayed, it isrecommended that the driver reduce the electrical loadsas much as possible. SeeDIC Warnings and Messageson page 4-67.
Inadvertent Power Battery Saver
This feature is designed to protect your vehicle’s batteryagainst drainage from the interior lamps, trunk lamp,glove box lamp, or the garage door opener. When theignition is turned off, the power to these features willautomatically turn off after 10 minutes. Power willbe restored for an additional 10 minutes if any door ortrunk is opened, or the courtesy lamp switch isturned on.
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Climate Controls
Dual Climate Control System
The heating, cooling, and ventilation for the vehicle canbe controlled with this system.
A. Fan Control
B. Display
C. Air Delivery Mode Control
D. Driver and Passenger Temperature Controls
E. Air Conditioning
F. Outside Air or AUX
G. Recirculation
H. PASS (Passenger Climate Control)
I. Rear Window Defogger
Dual Climate Control System
Dual Climate Control System for Vehicles withRear Climate Control
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Lane Departure Warning (LDW)
Light
For vehicles with the lanedeparture warning system,this light briefly comeson green, while starting thevehicle, to indicate that itis working.
If it does not, have the vehicle serviced by yourdealer/retailer. If the system is working normally theindicator light will then go off.
This light also comes on green if the system detects aleft or right lane marking. It flashes, changes toamber and three beeps sound if a detected lane markingis crossed without using a turn signal. For moreinformation, see the Index in the Navigation Manual.
Engine Coolant Temperature
Warning Light
The engine coolanttemperature warning lightcomes on when theengine is very hot.
This light also comes on briefly when the vehicle isstarted.
If the light does not go out or comes on and stays onwhile driving, there may be a problem with the coolingsystem. Driving with engine coolant temperature light oncould cause the vehicle to overheat, seeOverheatedEngine Protection Operating Mode on page 6-29.SeeEngine Overheating on page 6-27andDICWarnings and Messages on page 4-67for moreinformation.
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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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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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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