
Black plate (25,1)Cadillac DTS Owner Manual - 2011
A. Coolant Surge Tank with Pressure Cap
B. Electric Engine Cooling Fans
{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.(Continued)
WARNING: (Continued)
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
®can
cause premature engine, heater core, or radiator
corrosion. In addition, the engine coolant could
require changing sooner, at 50 000 km (30,000 miles)
or 24 months, whichever occurs first. Any repairs
would not be covered by the vehicle warranty.
Always use DEX-COOL (silicate-free) coolant in the
vehicle.
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Black plate (26,1)Cadillac DTS Owner Manual - 2011
Engine Coolant
The cooling system in the vehicle is filled with
DEX-COOL®engine coolant. This coolant is designed
to 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 to
check and add coolant when it is low. If there is a
problem with engine overheating, see Engine
Overheating on page 6‑29.
What to Use
{WARNING:
Adding only plain water or some other liquid to the
cooling system can be dangerous. Plain water
and other liquids, can boil before the proper
coolant mixture will. The vehicle's coolant warning
system is set for the proper coolant mixture. With
plain water or the wrong mixture, the engine could
get too hot but you would not get the overheat
warning. The engine could catch fire and you or
others could be burned. Use a 50/50 mixture of
clean, drinkable water and DEX-COOL coolant. Use a 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant. If using this mixture, nothing else
needs to be added. This mixture:
.Gives freezing protection down to −34°F (−37°C),
outside temperature.
.Gives boiling protection up to 265°F (129°C),
engine temperature.
.Protects against rust and corrosion.
.Will not damage aluminum parts.
.Helps keep the proper engine temperature.
Notice: If an improper coolant mixture is used, the
engine could overheat and be badly damaged. The
repair cost would not be covered by the vehicle
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core, and
other parts.
Notice: If extra inhibitors and/or additives are used
in the vehicle's cooling system, the vehicle could be
damaged. Use only the proper mixture of the engine
coolant listed in this manual for the cooling system.
See Recommended Fluids and Lubricants
on
page 7‑9for more information.
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Black plate (27,1)Cadillac DTS Owner Manual - 2011
Checking Coolant
The vehicle must be on a level surface when checking
the coolant level.
Check to see if coolant is visible in the coolant recovery
tank. If the coolant inside the coolant recovery tank is
boiling, do not do anything else until it cools down.
If coolant is visible but the coolant level is not at or
above the FULL COLD mark, add a 50/50 mixture of
clean, drinkable water and DEX-COOL
®coolant at the
coolant recovery tank, but be sure the cooling system is
cool before this is done. See Engine Coolant
on
page 6‑26for 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 fill
procedure. Failure to follow this procedure could
cause the engine to overheat and be severely
damaged.
{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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Black plate (28,1)Cadillac DTS Owner Manual - 2011
{WARNING:
Steam and scalding liquids from a hot cooling
system can blow out and burn you badly. They are
under pressure, and if you turn the surge tank
pressure cap—even a little —they can come out
at high speed. Never turn the cap when the
cooling system, including the surge tank pressure
cap, is hot. Wait for the cooling system and surge
tank pressure cap to cool if you ever have to turn
the pressure cap.
If no coolant is visible in the surge tank, add coolant as
follows:
1. Remove the coolant surge tank pressure
cap when the cooling
system, including the
coolant surge tank
pressure cap and
upper radiator hose, is
no longer hot. Turn the pressure cap slowly counterclockwise.
If you hear a hiss, wait for that to stop. A hiss
means there is still some pressure left.
2. Keep turning the cap and remove it.
3. Fill the coolant surge tank with the proper
mixture to the FULL
COLD mark on the
side of the coolant
surge tank.
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Black plate (29,1)Cadillac DTS Owner Manual - 2011
4.6L L37 Engine shown, 4.6L LD8 Engine similar
4. With the coolant surge tank cap off, start the engine and let it run until you can feel the upper
radiator hose getting hot. Watch out for the engine
cooling fans.
By this time, the coolant level inside the coolant
surge tank may be lower. If the level is lower, add
more of the proper mixture to the coolant surge
tank until the level reaches the FULL COLD mark
on the side of the coolant surge tank.
5. Replace the cap. Be sure the cap is hand‐tight and fully seated. Notice:
If the pressure cap is not tightly installed,
coolant loss and possible engine damage may
occur. Be sure the cap is properly and tightly
secured.
If coolant is needed, add the proper DEX-COOL
®
coolant mixture at the coolant recovery tank.
Engine Overheating
The vehicle has several indicators to warn of engine
overheating.
There is an engine temperature warning light and/or
gauge on the instrument panel cluster. See Engine
Coolant Temperature Warning Light
on page 4‑53and
Engine Coolant Temperature Gauge on page 4‑53.
The vehicle may also display a ENGINE OVERHEATED
IDLE ENGINE message or an ENGINE OVERHEATED
STOP ENGINE message displayed in the Driver
Information Center (DIC). See DIC Warnings and
Messages
on page 4‑65for more information. You will
also hear a chime.
The decision may be made not to lift the hood when
this warning appears, but instead get service help right
away. See Roadside Service on page 8‑7.
If the decision is made to lift the hood , make sure the
vehicle is parked on a level surface.
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Black plate (30,1)Cadillac DTS Owner Manual - 2011
Then check to see if the engine cooling fans are
running. If the engine is overheating, both fans should
be running. If they are not, do not continue to run the
engine and have the vehicle serviced.
Notice:Engine damage from running the engine
without coolant is not covered by the warranty.
Notice: If the engine catches fire while driving with
no coolant, the vehicle can be badly damaged. The
costly repairs would not be covered by the vehicle
warranty. See Overheated Engine Protection
Operating Mode
on page 6‑31for information on
driving to a safe place in an emergency.
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.
(Continued)
WARNING: (Continued)
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 6‑31for information on driving to
a safe place in an emergency.
If No Steam Is Coming From The
Engine Compartment
If an engine overheat warning is displayed but no steam
can be seen or heard, the problem may not be too
serious. Sometimes the engine can get a little too hot
when the vehicle:
.Climbs a long hill on a hot day.
.Stops after high-speed driving.
.Idles for long periods in traffic.
.Tows a trailer.
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Black plate (72,1)Cadillac DTS Owner Manual - 2011
Wheel Alignment and Tire Balance
The tires and wheels on your vehicle were aligned and
balanced carefully at the factory to give you the longest
tire life and best overall performance. Adjustments
to wheel alignment and tire balancing will not be
necessary on a regular basis. However, if you notice
unusual tire wear or your vehicle pulling to one side or
the other, the alignment might need to be checked.
If you notice your vehicle vibrating when driving on a
smooth road, the tires and wheels might need to be
rebalanced. See your dealer for proper diagnosis.
Wheel Replacement
Replace any wheel that is bent, cracked or badly rusted
or corroded. If wheel nuts keep coming loose, the
wheel, wheel bolts and wheel nuts should be replaced.
If the wheel leaks air, replace it. Some aluminum wheels
can sometimes be repaired. See your GM dealer if any
of these conditions exist.
Your GM dealer will know the kind of wheel you need.
Each new wheel should have the same load-carrying
capacity, diameter, width, offset and be mounted the
same way as the one it replaces.
If you need to replace any of your wheels, wheel bolts,
wheel nuts, or Tire Pressure Monitor System (TPMS)
sensors, replace them only with new GM originalequipment parts. This way, you will be sure to have the
right wheel, wheel bolts, wheel nuts, and TPMS sensors
for your vehicle.
{WARNING:
Using the wrong replacement wheels, wheel bolts,
or wheel nuts on your vehicle can be dangerous.
It could affect the braking and handling of your
vehicle, make your tires lose air and make you
lose control. You could have a collision in which
you or others could be injured. Always use the
correct wheel, wheel bolts, and wheel nuts for
replacement.
Notice: The wrong wheel can also cause problems
with bearing life, brake cooling, speedometer or
odometer calibration, headlamp aim, bumper height,
vehicle ground clearance, and tire or tire chain
clearance to the body and chassis.
If your vehicle is a professional model, the wheels have
a unique offset and bolt hole diameter. Each of the
wheels on the professional vehicle have eight wheels
nuts. The wheels on the non-professional vehicle
have five wheel nuts. See Changing a Flat Tire
on
page 6‑83for more information.
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Black plate (106,1)Cadillac DTS Owner Manual - 2011
Fuses Usage
9Engine Control Module (ECM),
Powertrain Control Module (PCM)
10 Climate Control System, Instrument
Panel Cluster Ignition 1
11 Airbag System
12 Horn
13 Windshield Wiper
14 Fog Lamps
15 Right High-Beam Headlamp
16 Left High-Beam Headlamp
17 Left Low-Beam Headlamp
18 Right Low-Beam Headlamp
19 Windshield Washer Pump Motor
20 Left Front Cornering Lamp
21 Right Front Cornering Lamp
22 Air Pump (J-Case)
23 Antilock Brake System (ABS)
(J-Case)
Fuses Usage
24 Starter (J-Case)
25Antilock Brake System (ABS) Motor
(J-Case)
26 Cooling Fan 2 (J-Case)
27 Cooling Fan 1 (J-Case)
Relays Usage
29 Powertrain
30 Starter
31 Cooling Fan 2
32 Cooling Fan 3
33 Cooling Fan 1
34 Air Conditioning Clutch
35 Air Injection Reactor (AIR) Solenoid
36 Ignition
37 Air Pump
6-106