2006 CADILLAC DTS PROFESSIONAL brake

Trailer Brakes
Because your vehicle has anti-lock brakes, do not try to
tap into your 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 trailer
brakes so you will be able to maintain them properly.
Driving with a Trailer
Towing a trailer requires a certain amount of experience.
Before setting out for the open road, you will want to
get to know your rig. Acquaint yourself with the feel of
handling and braking with the added weight of the trailer.
And always keep in mind that the vehicle you are
driving is now a good deal longer and not nearly as
responsive as your vehicle is by itself.
Before you start, check the trailer hitch and platform,
parts and attachments, safety chains, electrical
connector, lamps, tires and mirror adjustment. If the
trailer has electric brakes, start your vehicle and trailer
moving and then apply the trailer brake controller
by hand to be sure the brakes are working. This lets
you check your electrical connection at the same time.
During your trip, check occasionally to be sure that
the load is secure, and that the lamps and any trailer
brakes are still working.
Following Distance
Stay at least twice as far behind the vehicle ahead as
you would when driving your vehicle without a trailer.
This can help you avoid situations that require
heavy braking and sudden turns.
Passing
You will need more passing distance up ahead when
you are towing a trailer. And, because the vehicle
is a good deal longer, you will need to go much farther
beyond the passed vehicle before you can return to
your lane.
Backing Up
Hold the bottom of the steering wheel with one hand.
Then, to move the trailer to the left, just move that hand
to the left. To move the trailer to the right, move your
hand to the right. Always back up slowly and, if possible,
have someone guide you.
4-42

Making Turns
Notice:Making very sharp turns while trailering
could cause the trailer to come in contact with the
vehicle. Your vehicle could be damaged. Avoid
making very sharp turns while trailering.
When you are turning with a trailer, make wider turns
than normal. Do this so your trailer will not strike
soft shoulders, curbs, road signs, trees or other
objects. Avoid jerky or sudden maneuvers. Signal
well in advance.
Turn Signals When Towing a Trailer
When you tow a trailer, your vehicle may need a
different turn signal asher and/or extra wiring. Check
with your dealer. The arrows on your instrument
panel will ash whenever you signal a turn or lane
change. Properly hooked up, the trailer lamps will also
ash, telling other drivers you are about to turn,
change lanes or stop.
When towing a trailer, the arrows on your instrument
panel will ash for turns even if the bulbs on the trailer
are burned out. Thus, you may think drivers behind
you are seeing your signal when they are not. It
is important to check occasionally to be sure the trailer
bulbs are still working.
Driving on Grades
Reduce speed and shift to a lower gearbeforeyou start
down a long or steep downgrade. If you do not shift
down, you might have to use your brakes so much that
they would get hot and no longer work well.
On a long uphill grade, shift down and reduce your
speed to around 45 mph (70 km/h) to reduce the
possibility of the engine and the transmission
overheating.
Parking on Hills
{CAUTION:
You really should not park your vehicle, with a
trailer attached, on a hill. If something goes
wrong, your rig could start to move. People
can be injured, and both your vehicle and the
trailer can be damaged.
But if you ever have to park your rig on a hill, here is
how to do it:
1. Apply your regular brakes, but do not shift into
PARK (P).
2. Have someone place chocks behind the
trailer wheels.
4-43

3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb the load.
4. Reapply the regular brakes. Then shift into
PARK (P) rmly and apply your parking brake.
5. Release the regular brakes.
When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
Start your engine,
Shift into a gear, and
Make sure the parking brake has released.
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 store
the chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you are
pulling a trailer. See the Maintenance Schedule for
more on this. Things that are especially important in
trailer operation are automatic transaxle uid (do
not overll), engine oil, drive belt, cooling system and
brake system. Each of these is covered in this manual,
and the Index will help you nd them quickly. If you
are trailering, it is a good idea to review this information
before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Engine Cooling When Trailer Towing
Your cooling system may temporarily overheat during
severe operating conditions. SeeEngine Overheating on
page 5-25.
4-44

Service............................................................5-3
Accessories and Modications..........................5-3
California Proposition 65 Warning.....................5-3
Doing Your Own Service Work.........................5-4
Adding Equipment to the Outside
of Your Vehicle...........................................5-5
Fuel................................................................5-5
Gasoline Octane............................................5-5
Gasoline Specications....................................5-6
California Fuel...............................................5-6
Additives.......................................................5-6
Fuels in Foreign Countries...............................5-7
Filling the Tank..............................................5-8
Filling a Portable Fuel Container.....................5-10
Checking Things Under the Hood....................5-10
Hood Release..............................................5-11
Engine Compartment Overview.......................5-12
Engine Oil...................................................5-13
Engine Oil Life System..................................5-16
Engine Air Cleaner/Filter................................5-18
Automatic Transaxle Fluid..............................5-19
Engine Coolant.............................................5-22
Coolant Surge Tank Pressure Cap..................5-25
Engine Overheating.......................................5-25
Overheated Engine Protection Operating Mode . . .5-27
Cooling System............................................5-28Power Steering Fluid.....................................5-33
Windshield Washer Fluid................................5-34
Brakes........................................................5-35
Battery........................................................5-37
Jump Starting...............................................5-39
Headlamp Aiming...........................................5-44
Bulb Replacement..........................................5-47
High Intensity Discharge (HID) Lighting............5-47
Windshield Wiper Blade Replacement..............5-47
Tires..............................................................5-49
Tire Sidewall Labeling...................................5-50
Tire Terminology and Denitions.....................5-53
Ination - Tire Pressure.................................5-56
Tire Pressure Monitor System.........................5-59
Tire Inspection and Rotation...........................5-63
When It Is Time for New Tires.......................5-64
Buying New Tires.........................................5-65
Different Size Tires and Wheels......................5-66
Uniform Tire Quality Grading..........................5-67
Wheel Alignment and Tire Balance..................5-69
Wheel Replacement......................................5-69
Tire Chains..................................................5-70
If a Tire Goes Flat........................................5-71
Changing a Flat Tire.....................................5-72
Section 5 Service and Appearance Care
5-1

Service
Your dealer knows your vehicle best and wants you to
be happy with it. We hope you will go to your dealer
for all your service needs. You will get genuine GM parts
and GM-trained and supported service people.
We hope you will want to keep your GM vehicle all GM.
Genuine GM parts have one of these marks:
Accessories and Modications
When you add non-GM accessories to your vehicle
they can affect your vehicle’s performance and safety,
including such things as, airbags, braking, stability,
ride and handling, emissions systems, aerodynamics,
durability, and electronic systems like anti-lock brakes,
traction control and stability control. Some of these
accessories may even cause malfunction or damage
not covered by warranty.
GM Accessories are designed to complement and
function with other systems on your vehicle. Your
GM dealer can accessorize your vehicle using genuine
GM Accessories. When you go to your GM dealer
and ask for GM Accessories, you will know that
GM-trained and supported service technicians will
perform the work using genuine GM Accessories.
California Proposition 65 Warning
Most motor vehicles, including this one, contain and/or
emit chemicals known to the State of California to
cause cancer and birth defects or other reproductive
harm. Engine exhaust, many parts and systems
(including some inside the vehicle), many uids, and
some component wear by-products contain and/or emit
these chemicals.
5-3

Filling a Portable Fuel Container
{CAUTION:
Never ll a portable fuel container while it is in
your vehicle. Static electricity discharge from
the container can ignite the gasoline vapor.
You can be badly burned and your vehicle
damaged if this occurs. To help avoid injury to
you and others:
Dispense gasoline only into approved
containers.
Do not ll a container while it is inside a
vehicle, in a vehicle’s trunk, pickup bed, or
on any surface other than the ground.
Bring the ll nozzle in contact with the
inside of the ll opening before operating
the nozzle. Contact should be maintained
until the lling is complete.
Do not smoke while pumping gasoline.
Checking Things Under
the Hood
{CAUTION:
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.
{CAUTION:
Things that burn can get on hot engine parts
and start a re. These include liquids like fuel,
oil, coolant, brake uid, windshield washer and
other uids, 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.
5-10

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

Wait at least 30 minutes before checking the transaxle
uid level if you have been driving:
When outside temperatures are above 90°F (32°C).
At high speed for quite a while.
In heavy traffic — especially in hot weather.
While pulling a trailer.
To get the right reading, the uid should be at normal
operating temperature, which is 180°F to 200°F
(82°C to 93°C).
Get the vehicle warmed up by driving about
15 miles (24 km) when outside temperatures are
above 50°F (10°C). If it is colder than 50°F (10°C),
you may have to drive longer.
Checking the Fluid Level
Prepare you vehicle as follows:
1. Park your vehicle on a level place. Keep the engine
running.
2. With the parking brake applied, place the shift lever
in PARK (P).3. With your foot on the brake pedal, move the shift
lever through each gear range, pausing for about
three seconds in each range. Then, position
the shift lever in PARK (P).
4. Let the engine run at idle for three to ve minutes.
Then, without shutting off the engine, follow
these steps:
The transaxle uid cap is located next to the radiator
hose and below the engine air cleaner/lter assembly on
the driver’s side of the vehicle, and is marked TRANS
FLUID. SeeEngine Compartment Overview on
page 5-12for more information on location.
1. After removing the engine air cleaner/lter assembly
to reach the transaxle uid cap, turn the cap
counterclockwise to remove. Pull out the dipstick
and wipe it with a clean rag or paper towel.
2. Push it back in all the way, wait three seconds, and
then pull it back out again.
5-20