2005 CADILLAC STS coolant reservoir

Your vehicle may be equipped with front compartment
underhood sight shields, which surround the vehicle’s
engine cover. These sight shields will need to be
removed in order to access some of the underhood
components in your vehicle.
To remove the sight shields, turn the fasteners on each
shield to the left until they pop out. Then remove the
fasteners and lift the shields up and away from the
shock towers that support them.
After you have removed the sight shields (if equipped)
on the 3.6L V6 engine, here is what you will see:
A. Underhood Fuse Block. SeeUnderhood Fuse Block
on page 5-96.
B. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-32.
C. Battery. SeeBattery on page 5-37.D. Passenger Compartment Air Filter. SeePassenger
Compartment Air Filter on page 3-58.
E. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-31.
F. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-15.
G. Engine Oil Dipstick (Out of View). See “Checking
Engine Oil” underEngine Oil on page 5-15.
H. Brake Master Cylinder Reservoir. See “Brake Fluid”
underBrakes on page 5-34.
I. Engine Coolant Surge Tank and Pressure Cap. See
Coolant Surge Tank Pressure Cap on page 5-24
andCooling System on page 5-27.
J. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-20.
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After you have removed the sight shields (if equipped)
on the 4.6L V8 engine, here is what you will see:
A. Underhood Fuse Block. SeeUnderhood Fuse Block
on page 5-96.
B. Battery. SeeBattery on page 5-37.
C. Passenger Compartment Air Filter. SeePassenger
Compartment Air Filter on page 3-58.
D. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-32.
E. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-31.
F. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-15.
G. Engine Oil Dipstick (Out of View). See “Checking
Engine Oil” underEngine Oil on page 5-15.
H. Brake Master Cylinder Reservoir. See “Brake Fluid”
underBrakes on page 5-34.
I. Engine Coolant Surge Tank and Pressure Cap. See
Coolant Surge Tank Pressure Cap on page 5-24
andCooling System on page 5-27.
J. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-20.If your vehicle is equipped with front compartment
underhood sight shields, before closing the hood be sure
to replace the sight shields. To replace the shields,
locate the ribs on the underside of each shield and guide
the ribs on to the supporting shock towers. Then
insert the fasteners into the top of the shield and push
the fasteners back into place.
Engine Oil
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.
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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.
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Adding Washer Fluid
The Check Washer Fluid message will appear on the
Driver Information Center (DIC) when the uid level
is low. SeeDIC Warnings and Messages on page 3-78
for more information.
Open the cap with the
washer symbol on it. Add
washer uid until the
tank is full. SeeEngine
Compartment Overview on
page 5-12for reservoir
location.Notice:When using concentrated washer uid, follow
the manufacturer’s instructions for adding
water.
Do not mix water with ready-to-use washer uid.
Water can cause the solution to freeze and
damage your washer uid tank and other parts
of the washer system. Also, water does not
clean as well as washer uid.
Fill your washer uid tank only three-quarters
full when it is very cold. This allows for
expansion if freezing occurs, which could
damage the tank if it is completely full.
Do not use engine coolant (antifreeze) in your
windshield washer. It can damage your washer
system and paint.
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