2005 CADILLAC STS radiator cap

If you have to add coolant more than once or twice a
year, have your dealer check your cooling system.
Notice:If you use the proper coolant, you do not
have to add extra inhibitors or additives which claim
to improve the system. These can be harmful.
Checking Coolant
The coolant surge tank and pressure cap are located on
the driver’s side of the vehicle, toward the rear of the
engine compartment. SeeEngine Compartment
Overview on page 5-12for more information on location.
{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/FROID line on the side of the surge tank.
Follow the arrow from the top of the tank down the side
to the horizontal mark.
If the Check Coolant Level message in the Driver
Information Center (DIC) comes on and stays on,
it means you are low on engine coolant. See
DIC Warnings and Messages on page 3-78
for more information.
5-23

When the engine is cold, the coolant level should be at
or slightly above the FULL COLD/FROID line on the
side of the coolant surge tank. If it is not, you may have
a leak at the pressure cap or in the radiator hoses,
heater hoses, radiator, water pump or somewhere else
in the cooling system.
{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 5-26for 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.
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 coolant level is not at the FULL COLD/FROID
line on the side of the coolant surge tank, add a
50/50 mixture ofclean, drinkable waterand DEX-COOL
®
coolant at the coolant surge tank, but be sure the
cooling system, including the coolant surge tank
pressure cap, is cool before you do it. SeeEngine
Coolant on page 5-22for more information.
5-28

{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.
{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.
CAUTION: (Continued)
CAUTION: (Continued)
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.
5-29

If no coolant is visible in the surge tank, add coolant
as follows:
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 (left) about one-quarter turn and
then stop.
If you hear a hiss, wait for that to stop. A hiss
means there is still some pressure left.
2. Then keep turning the pressure cap slowly, and
remove it.3. Fill the coolant surge tank with the proper mixture,
to slightly above the FULL COLD/FROID line on the
side of the coolant surge tank.
5-30

4. With the coolant surge tank pressure cap off, start
the engine and let it run until you can feel the upper
radiator hose getting hot. The upper radiator
hose is the largest of the hoses which comes out of
the radiator, on the passenger’s side of the
vehicle. 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/FROID
line on the side of the coolant surge tank.
5. Then replace the pressure cap. Be sure the
pressure cap is hand-tight and fully seated.
Start the engine and allow it to warm up. If the Check
Coolant Level message does not appear on the
Driver Information Center, the coolant is at the proper ll
level. If a Check Coolant Level message does appear,
repeat Steps 1 to 3 then reinstall the pressure cap,
or see your GM dealer.Power Steering Fluid
The power steering uid
reservoir is located in the
center of the engine
compartment, toward the
front of the vehicle.
SeeEngine Compartment
Overview on page 5-12
for more information
on location.
When to Check Power Steering Fluid
It is not necessary to regularly check power steering uid
unless you suspect there is a leak in the system or
you hear an unusual noise. A uid loss in this system
could indicate a problem. Have the system inspected
and repaired.
5-31

Additional Required Services (cont’d)
Service and Miles (Kilometers)25,000
(41 500)50,000
(83 000)75,000
(125 000)100,000
(166 000)125,000
(207 500)150,000
(240 000)
Engine cooling system service
(or every ve years, whichever occurs
rst).An Emission Control Service.
See footnote (j).•
Inspect engine accessory drive belt.
An Emission Control Service.•
Maintenance Footnotes
†The U.S. Environmental Protection Agency or the
California Air Resources Board has determined that the
failure to perform this maintenance item will not nullify
the emission warranty or limit recall liability prior to
the completion of the vehicle’s useful life. We, however,
urge that all recommended maintenance services be
performed at the indicated intervals and the
maintenance be recorded.
(a)Visually inspect brake lines and hoses for proper
hook-up, binding, leaks, cracks, chang, etc. Inspect
disc brake pads for wear and rotors for surface
condition. Inspect other brake parts, including calipers,
parking brake, etc.(b)Visually inspect front and rear suspension and
steering system for damaged, loose, or missing parts or
signs of wear. Inspect power steering lines and hoses
for proper hook-up, binding, leaks, cracks, chang, etc.
(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.
6-7

(d)Visually inspect wiper blades for wear or cracking.
Replace blade inserts 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 transmission 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.
Uses such as limousine service.
Uses such as high performance operation.
If you do not use your vehicle under any of these
conditions, the uid and lter do not require change.
(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.
6-8