2006 CADILLAC DTS PROFESSIONAL coolant level

ENGINE OIL LOW ADD OIL
This message will display when the oil level is low. See
Engine Oil on page 5-13for more information on
checking your engine oil.
ENGINE OVERHEATED IDLE ENGINE
Notice:If you drive your vehicle while the engine is
overheating, severe engine damage may occur. If
an overheat warning appears on the instrument
panel cluster and/or DIC, stop the vehicle as soon
as possible. Do not increase the engine speed above
normal idling speed. SeeEngine Overheating on
page 5-25for more information.
This message will display when the engine coolant
temperature is too hot. Stop and allow the vehicle to idle
until it cools down. SeeEngine Coolant Temperature
Warning Light on page 3-65.
SeeOverheated Engine Protection Operating Mode on
page 5-27for information on driving to a safe place
in an emergency.
ENGINE OVERHEATED STOP ENGINE
Notice:If you drive your vehicle while the engine
is overheating, severe engine damage may occur.
If an overheat warning appears on the instrument
panel cluster and/or DIC, stop the vehicle as soon as
possible. Do not increase the engine speed above
normal idling speed. SeeEngine Overheating
on page 5-25for more information.
This message will display when the engine has
overheated. Immediately look for a safe place to pull
your vehicle over and turn the engine off right away to
avoid severe engine damage. SeeEngine Overheating
on page 5-25andOverheated Engine Protection
Operating Mode on page 5-27. A chime will also sound
when this message is displayed.
ENGINE POWER REDUCED
This message will display when the engine power is
being reduced to protect the engine from damage. There
could be several malfunctions that might cause this
message. Reduced engine power can affect the vehicle’s
ability to accelerate. If this message is on, but there is no
reduction in performance, proceed to your destination.
The performance may be reduced the next time the
vehicle is driven. The vehicle may be driven at a reduced
speed while this message is on, but acceleration and
speed may be reduced. Anytime this message stays on,
the vehicle should be taken to your GM dealer for service
as soon as possible.
3-79

A. Underhood Fuse Block. SeeUnderhood Fuse Block
on page 5-93.
B. Remote Positive (+) Terminal. SeeJump Starting on
page 5-39.
C. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-34.
D. Engine Coolant Surge Tank and Pressure Cap. See
Coolant Surge Tank Pressure Cap on page 5-25
andCooling System on page 5-28.
E. Power Steering Fluid. SeePower Steering Fluid on
page 5-33.
F. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-13.
G. Engine Oil Dipstick. See “Checking Engine Oil”
underEngine Oil on page 5-13.
H. Brake Master Cylinder Reservoir. See “Brake Fluid”
underBrakes on page 5-35.
I. Automatic Transaxle Fluid Cap and Dipstick (Out of
View). SeeAutomatic Transaxle Fluid on page 5-19.
J. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-18.Engine Oil
If the ENGINE OIL LOW ADD OIL message appears
on the Driver Information Center (DIC), it means
you need to check your engine oil level right away. See
“ENGINE OIL LOW ADD OIL” underDIC Warnings
and Messages on page 3-76.
You should check your engine oil level regularly; this is
an added reminder.
Checking Engine Oil
It is a good idea to check your engine oil every time you
get fuel. In order to get an accurate reading, the oil
must be warm and the vehicle must be on level ground.
The engine oil dipstick handle is a yellow loop. See
Engine Compartment Overview on page 5-12for
the location of the engine oil dipstick.
1. Turn off the engine and give the oil several minutes
to drain back into the oil pan. If you do not do this,
the oil dipstick might not show the actual level.
2. Pull out the dipstick and clean it with a paper towel
or cloth, then push it back in all the way. Remove it
again, keeping the tip down, and check the level.
5-13

Checking Coolant
The engine coolant surge
tank is located toward the
rear of the engine
compartment on the
passenger’s side of
the vehicle.
For more information on location, seeEngine
Compartment Overview on page 5-12.{CAUTION:
Turning the surge tank pressure cap when the
engine and radiator are hot can allow steam
and scalding liquids to blow out and burn you
badly. Never turn the surge tank pressure
cap — even a little — when the engine and
radiator are hot.
The vehicle must be on a level surface. When your
engine is cold, the coolant level should be at the FULL
COLD mark, located on the side of the surge tank
that faces the engine.
5-24

{CAUTION:
An electric engine cooling fan under the hood
can start up even when the engine is not
running and can injure you. Keep hands,
clothing and tools away from any underhood
electric fan.
If the coolant inside the coolant surge tank is boiling, do
not do anything else until it cools down. The vehicle
should be parked on a level surface.
{CAUTION:
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 re, and you could be
burned. Get any leak xed before you drive the
vehicle.If there seems to be no leak, with the engine on, check
to see if the electric engine cooling fans are running.
If the engine is overheating, both fans should be
running. If they are not, your vehicle needs service.
Notice:Engine damage from running your engine
without coolant is not covered by your warranty. See
Overheated Engine Protection Operating Mode on
page 5-27for information on driving to a safe place
in an emergency.
Notice:Using coolant other than DEX-COOL
®may
cause premature engine, heater core or radiator
corrosion. In addition, the engine coolant
may require changing sooner, at 30,000 miles
(50 000 km) or 24 months, whichever occurs rst.
Any repairs would not be covered by your warranty.
Always use DEX-COOL
®(silicate-free) coolant in
your vehicle.
5-29

How to Add Coolant to the Coolant
Surge Tank
If you have not found a problem yet, check to see if
coolant is visible in the surge tank. If coolant is visible
but the level is not at the FULL COLD mark located
on the side of the surge tank, add enough of a
50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant at the coolant surge tank to
bring the level to the FULL COLD mark, but be sure
the cooling system, including the coolant surge
tank pressure cap (if equipped), is cool before you
do it. SeeEngine Coolant on page 5-22for more
information.If no coolant is visible in the surge tank, add coolant as
follows:
{CAUTION:
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 coolant
surge tank pressure cap — even a little — they
can come out at high speed. Never turn the
cap when the cooling system, including the
coolant surge tank pressure cap, is hot. Wait
for the cooling system and coolant surge tank
pressure cap to cool if you ever have to turn
the pressure cap.
5-30

2. Then 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.
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. Then replace the cap. Be sure the cap is hand-tight
and fully seated.
4.6L L37 Engine shown, 4.6L LD8 Engine similar
5-32

Scheduled Maintenance
Service MaintenanceIMaintenanceII
Change engine oil and lter. SeeEngine Oil on page 5-13. Reset oil
life system. SeeEngine Oil Life System on page 5-16.An Emission
Control Service.••
Visually check for any leaks or damage.See footnote (k).••
Inspect engine air cleaner lter. If necessary, replace lter. SeeEngine Air
Cleaner/Filter on page 5-18.See footnote (m).•
Rotate tires and check ination pressures and wear. SeeTire Inspection and
Rotation on page 5-63and “Tire Wear Inspection” inAt Least Once a Month
on page 6-9.••
Inspect brake system.See footnote (a).••
Check engine coolant and windshield washer uid levels and add uid
as needed.••
Perform any needed additional services. See “Additional Required Services” in
this section.••
Inspect suspension and steering components.See footnote (b).•
Inspect engine cooling system.See footnote (c).•
Inspect wiper blades.See footnote (d).•
Inspect restraint system components.See footnote (e).•
Lubricate body components.See footnote (f).•
Check transaxle uid level and add uid as needed.•
Replace passenger compartment air lter.See footnote (g).•
6-5

(c)Visually inspect hoses and have them replaced if they
are cracked, swollen, or deteriorated. Inspect all pipes,
ttings and clamps; replace with genuine GM parts as
needed. To help ensure proper operation, a pressure test
of the cooling system and pressure cap and cleaning the
outside of the radiator and air conditioning condenser is
recommended at least once a year.
(d)Visually inspect wiper blades for wear or cracking.
Replace wiper blades that appear worn or damaged
or that streak or miss areas of the windshield.
(e)Make sure the safety belt reminder light and all your
belts, buckles, latch plates, retractors, and anchorages
are working properly. Look for any other loose or
damaged safety belt system parts. If you see anything
that might keep a safety belt system from doing its
job, have it repaired. Have any torn or frayed safety belts
replaced. Also look for any opened or broken airbag
coverings, and have them repaired or replaced.
The airbag system does not need regular maintenance.
(f)Lubricate all key lock cylinders. Lubricate all
hinges and latches, including those for the hood, rear
compartment, glove box door, and console door.
More frequent lubrication may be required when
exposed to a corrosive environment. Applying silicone
grease on weatherstrips with a clean cloth will make
them last longer, seal better, and not stick or squeak.
(g)If you drive regularly under dusty conditions, the lter
may require replacement more often.(h)Change automatic transaxle uid and lter if the
vehicle is mainly driven under one or more of these
conditions:
In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Professional vehicle uses, such as limousine
service.
Uses such as high performance operation.
(j)Drain, ush, and rell cooling system. This service
can be complex; you should have your dealer perform
this service. See Engine Coolant on page 5-22 for
what to use. Inspect hoses. Clean radiator, condenser,
pressure cap, and ller neck. Pressure test the
cooling system and pressure cap.
(k)A uid loss in any vehicle system could indicate a
problem. Have the system inspected and repaired
and the uid level checked. Add uid if needed.
(l)Inspect throttle body bore and valve plates for
deposits. Open the throttle valve and inspect all
surfaces. Clean as required.
(m)If you drive regularly under dusty conditions, inspect
the lter at each engine oil change.
(n)Visually inspect belt for fraying, excessive cracks, or
obvious damage. Replace belt if necessary.
6-8