cooling CADILLAC DTS PROFESSIONAL 2006 1.G User Guide

Cooling System
When you decide it is safe to lift the hood, here is what you will see:
A. Coolant Surge Tank with Pressure Cap B. Electric Engine Cooling Fans4.6L L37 Engine shown, 4.6L LD8 Engine similar
5-28

{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

{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will. Your
vehicle’s coolant warning system is set for the
proper coolant mixture. With plain water or the
wrong mixture, your engine could get too hot
but you would not get the overheat warning.
Your engine could catch re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.
Notice:In cold weather, water can freeze and crack
the engine, radiator, heater core and other parts.
Use the recommended coolant and the proper
coolant mixture.
{CAUTION:
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.
1. You can 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.
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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

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 may need to be checked. If you notice your
vehicle vibrating when driving on a smooth road, your
tires and wheels may 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 or
wheel nuts, replace them only with new GM original
equipment parts. This way, you will be sure to have the
right wheel, wheel bolts and wheel nuts for your vehicle.
{CAUTION:
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 ve wheel nuts. SeeChanging a Flat Tire on
page 5-72for more information.
5-69

Fuses Usage
F1 Spare
F2 Driver’s Side Low-Beam
F3 Passenger’s Side Low-Beam
F4 Airbag Ignition
F5 Engine Control Module
F6 Transaxle Ignition
F7 Spare
F8 Spare
F9 Spare
F10 High-Beam Headlamp
F11 High-Beam Headlamp
F12 Windshield Washer Pump
F13 Spare
F14Climate Controls, Instrument Panel
Cluster
F15 Spare
F16 Fog Lamps
F17 Horn
F18 Windshield Wiper
F19 Driver’s Side Corner Lamp
F20 Passenger’s Side Corner Lamp
F21 Oxygen Sensor
F22 PowertrainFuses Usage
F23Engine Control Module (ECM),
Crank
F24 Injector Coil
F25 Injector Coil
F26 Air Conditioning
F27 Air Solenoid
F28Engine Control Module, Transaxle
Control Module (ECM/TCM)
F29 Spare
F30 Spare
F31 Spare
F32 Spare
J-Case Fuse Usage
JC1 Heated Windshield Washer
JC2 Cooling Fan 1
JC3 Spare
JC4 Crank
JC5 Cooling Fan 2
JC6 Anti-lock Brake System 2
JC7 Anti-lock Brake System 1
JC8 Air Pump
5-95

Relays Usage
R1 Cooling Fan 1
R2 Cooling Fan
R3 Crank
R4 Powertrain
R5 Spare
R6 Run/Crank
R7 Cooling Fan 2
R8 Windshield Wiper
R9 Air Pump
R10 Windshield Wiper High
R11 Air Conditioning
R12 Air Solenoid
Rear Underseat Fuse Block
The rear fuse block is located under the rear seat on
the driver’s side. The rear seat cushion must be
removed to access the rear fuse block.
Removing the Rear Seat Cushion
Notice:If you touch the exposed wires with the
metal on the seat cushion, you could cause a short
that could damage the battery and or wires.Avoid contact between the rear seat and the fuse
center whenever you remove or reinstall the rear
seat. Do not remove covers from any of the covered
parts, and do not store anything under the seats.
To remove the rear seat cushion, do the following:
1. Pull up on the front of the cushion to release the
front hooks.
2. Pull the cushion up and out toward the front of the
vehicle.
To access the fuse block, pull out and lift up on the
cover latch, located at the end of the fuse block, near
the battery cable.
5-96

Capacities and Specications
The following approximate capacities are given in English and metric conversions. SeeRecommended Fluids and
Lubricants on page 6-12for more information.
ApplicationCapacities
English Metric
Air Conditioning Refrigerant 1.43 lbs 0.65 kg
Cooling System 12.9 qt 12.2 L
Engine Oil with Filter 7.5 qt 7.1 L
Fuel Tank 18.5 gal 70.0 L
Transaxle 15.0 qt 14.2 L
Wheel Nut Torque 100 lb ft 140Y
All capacities are approximate. When adding, be sure to ll to the approximate level as recommended in this
manual. Recheck uid level after lling.
Engine Specications
Engine VIN Code Transaxle Spark Plug Gap
4.6L DOHC V8 Y Automatic 0.050 inches (1.27 mm)
4.6L DOHC V8 9 Automatic 0.050 inches (1.27 mm)
5-101

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