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VEHICLE CARE 327
1. Windshield Washer Fluid Reservoir.See Washer Fluid 0343.
2. Engine Coolant Surge Tank and Pressure Cap. See Cooling System
0 338.
3. Engine Air Cleaner/Filter 0336.
4. Engine Cooling Fan (Out of View). See Cooling System 0338.
5. Engine Oil Fill Cap. See Engine Oil
0 331.
6. Engine Oil Dipstick. See Engine Oil
0 331.
7. Remote Positive (+) Battery Terminal. See Jump Starting - North
America 0390.
8. Brake Fluid Reservoir. See Brake
Fluid 0348.
9. Remote Negative (-) Battery Terminal. See Jump Starting - North
America 0390.
10. Engine Compartment Fuse Block
0356.
Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-15283641) -
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VEHICLE CARE 329
1. Windshield Washer Fluid Reservoir.See Washer Fluid 0343.
2. Engine Coolant Surge Tank and Pressure Cap. See Cooling System
0 338.
3. Engine Air Cleaner/Filter 0336.
4. Engine Cooling Fan (Out of View). See Cooling System 0338.
5. Engine Oil Fill Cap. See Engine Oil
0 331.
6. Cooling System Air Bleeder Cap. See Cooling System 0338.
7. Engine Oil Dipstick. See Engine Oil
0 331.
8. Remote Positive (+) Battery Terminal. See Jump Starting - North
America 0390.
9. Brake Fluid Reservoir. See Brake
Fluid 0348.
10. Remote Negative (-) Battery Terminal. See Jump Starting - North
America 0390.
11. Engine Compartment Fuse Block. SeeEngine Compartment Fuse Block
0356.
Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-15283641) -
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1. Windshield Washer Fluid Reservoir.See Washer Fluid 0343.
2. Engine Coolant Surge Tank and Pressure Cap. See Cooling System
0 338.
3. Engine Air Cleaner/Filter 0336.
4. Engine Cooling Fan (Out of View). See Cooling System 0338.
5. Engine Oil Fill Cap. See Engine Oil
0 331.
6. Engine Oil Dipstick. See Engine Oil
0 331.
7. Remote Positive (+) Battery Terminal. See Jump Starting - North
America 0390.
8. Brake/Clutch Fluid Reservoir. See Brake Fluid 0348.
9. Remote Negative (-) Battery Terminal. See Jump Starting - North
America 0390.
10. Engine Compartment Fuse Block. See Engine Compartment Fuse Block
0 356.Engine Oil
To ensure proper engine performance
and long life, careful attention must
be paid to engine oil. Following these
simple, but important steps will help
protect your investment:
.Use engine oil approved to the
proper specification and of the
proper viscosity grade. See
“Selecting the Right Engine Oil” in
this section.
.Check the engine oil level regularly
and maintain the proper oil level.
See “Checking Engine Oil” and
“When to Add Engine Oil” in this
section.
.Change the engine oil at the
appropriate time. See Engine Oil Life
System 0333.
.Always dispose of engine oil
properly. See “What to Do with Used
Oil” in this section.
Checking Engine Oil
Check the engine oil level regularly,
every 650 km (400 mi), especially prior
to a long trip. The engine oil dipstick
handle is a loop. See Engine
Compartment Overview 0326 for the
location.
{Warning
The engine oil dipstick handle may
be hot; it could burn you. Use a
towel or glove to touch the dipstick
handle.
If a low oil Driver Information Center
(DIC) message displays, check the oil
level.
Follow these guidelines:
.To get an accurate reading, park the
vehicle on level ground. Check the
engine oil level after the engine has
been off for at least two hours.
Checking the engine oil level on
steep grades or too soon after
engine shutoff can result in
incorrect readings. Accuracy
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Caution
If the air cleaner/filter is off, dirt
can easily get into the engine,
which could damage it. Always have
the air cleaner/filter in place when
driving.
Cooling System
The cooling system allows the engine
to maintain the correct working
temperature.
2.0L L4 Engine
1. Engine Coolant Surge Tank andPressure Cap
2. Engine Cooling Fan (Out of View)
2.7L L4 Engine
1. Engine Coolant Surge Tank and Pressure Cap
2. Engine Cooling Fan (Out of View)
3. Cooling System Air Bleeder Cap
3.6L V6 Engine
1. Engine Coolant Surge Tank and Pressure Cap
2. Engine Cooling Fan (Out of View)
{Warning
An underhood electric fan can start
up even when the engine is not
running and can cause injury. Keep
hands, clothing, and tools away
from any underhood electric fan.
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{Warning
Do not touch heater or radiator
hoses, or other engine parts. They
can be very hot and can burn you.
Do not run the engine if there is a
leak; all coolant could leak out.
That could cause an engine fire and
can burn you. Fix any leak before
driving the vehicle.
Engine Coolant
The cooling system in the vehicle is
filled with DEX-COOL engine coolant.
SeeMaintenance Schedule 0408 and
Recommended Fluids and Lubricants
0 417.
The following explains the cooling
system and how to check and add
coolant when it is low. If there is a
problem with engine overheating, see
Engine Overheating 0342.
What to Use
{Warning
Do not touch heater or radiator
hoses, or other engine parts. They
can be very hot and can burn you.
Do not run the engine if there is a
leak; all coolant could leak out.
That could cause an engine fire and
can burn you. Fix any leak before
driving the vehicle.
Use a 50/50 mixture of clean
drinkable water and DEX-COOL
coolant. This mixture:
.Gives freezing protection down to
−37 °C (−34 °F), outside temperature.
.Gives boiling protection up to
129 °C (265 °F), engine temperature.
.Protects against rust and corrosion.
.Will not damage aluminum parts.
.Helps keep the proper engine
temperature.
Caution
Do not use anything other than a
mix of DEX-COOL coolant that
meets GM Standard GMW3420 and
clean, drinkable water. Anything
else can cause damage to the
engine cooling system and the
vehicle, which would not be covered
by the vehicle warranty.
Never dispose of engine coolant by
putting it in the trash, pouring it on
the ground, or into sewers, streams,
or bodies of water. Have the coolant
changed by an authorized service
center, familiar with legal
requirements regarding used coolant
disposal. This will help protect the
environment and your health.
Checking Coolant
The vehicle must be on a level surface
when checking the coolant level.
It is normal to see coolant moving in
the upper coolant hose return line
when the engine is running. It is also
normal to see bubbles entering the
surge tank through the small hose.
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Check to see if coolant is visible in the
coolant surge tank. If the coolant
inside the coolant surge tank is
boiling, do not do anything else until
it cools down.
If coolant is visible but the coolant
level is not at or above the indicated
mark, add a 50/50 mixture of clean
drinkable water and DEX-COOL
coolant.
Be sure the cooling system is cool
before this is done.If no coolant is visible in the coolant
surge tank, add coolant as follows:
How to Add Coolant to the
Coolant Surge Tank
{Warning
Spilling coolant on hot engine parts
can burn you. Coolant contains
ethylene glycol and it will burn if
the engine parts are hot enough.
{Warning
Plain water, or other liquids such as
alcohol, can boil before the proper
coolant mixture will. With plain
water or the wrong mixture, the
engine could get too hot but there
would not be an overheat warning.
The engine could catch fire and you
or others could be burned.
{Warning
Steam and scalding liquids from a
hot cooling system are under
pressure. Turning the pressure cap,
even a little, can cause them to
come out at high speed and you
could be burned. Never turn the cap
when the cooling system, including
the pressure cap, is hot. Wait for
the cooling system and pressure
cap to cool.
Caution
Failure to follow the specific
coolant fill procedure could cause
the engine to overheat and could
cause system damage. If coolant is
not visible in the surge tank,
contact your dealer.
If no problem is found, check to see if
coolant is visible in the coolant surge
tank. If coolant is visible but the
coolant level is not at or above the
indicated mark, add a 50/50 mixture
of clean, drinkable water and
DEX-COOL coolant at the coolant
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surge tank, but be sure the cooling
system, including the coolant surge
tank pressure cap, is cool before you
do it.
2.0L L4 Engine and 3.6L
V6 Engine
Automatic Coolant Service Fill
Instructions
The vehicle is equipped with a service
feature that assists with filling and
removing air from the cooling system
after service of components or when
coolant is added after being to low.To use this feature:1. With a cold system, add coolant to
the indicated line on the
surge tank.
2. Replace the pressure cap on the surge tank.
3. Activate the service feature: 3.1. Connect the vehicle to a battery charger.
3.2. Turn the ignition to Service Mode. See Ignition Positions
0 232.
3.3. Turn off the air conditioning.
3.4. Set the parking brake. 3.5. At the same time, press the
accelerator and the brake
pedal for two seconds, then
release.
3.6. At the end of the cycle, check the coolant level in the surge
tank and add coolant if it is
below the indicated line. Turn
the ignition off, allow the
Electronic Control Module
(ECM) to go to sleep, about
two minutes, and repeat
Steps 3.2 –3.6.
Listen for pump activation and
movement of the control valves while
watching the level of the coolant in
the surge tank. If the tank empties,
turn the ignition off, carefully remove
the pressure cap, refill to the indicated
line, replace the pressure cap, and
repeat steps 3.2 –3.6.
The fill and air removal process will
run for approximately 15 minutes.
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Caution
If the pressure cap is not tightly
installed, coolant loss and engine
damage may occur. Be sure the cap
is properly and tightly secured.
2.7L L4 Engine
Automatic Coolant Service Fill
Instructions
The vehicle is equipped with a service
feature that assists with filling and
removing air from the cooling system
after service of components or when
coolant is added after being to low.
To use this feature:1. With a cold system unscrew the cooling system air bleeder cap.
If coolant can be seen through the
bleeder move to Step 3.
2. Add coolant through the surge tank until it is visible through the air
bleeder.
3. Replace the cooling system air bleeder cap.
4. Add coolant to the indicated line on the surge tank. 5. Replace the pressure cap on the
surge tank.
6. Activate the service feature: 6.1. Connect the vehicle to a battery charger.
6.2. Turn the ignition to Service Mode. See Ignition Positions
0 232.
6.3. Turn off the air conditioning.
6.4. Set the parking brake.
6.5. At the same time, press the accelerator and the brake
pedal for two seconds, then
release.
6.6. At the end of the cycle, check the coolant level in the surge
tank and add coolant if it is
below the indicated line. Turn
the ignition off, carefully
remove the pressure cap, refill
to the indicated line, replace
the pressure cap, and repeat
steps 6.2 –6.6.
Listen for pump activation and
movement of the control valves while
watching the level of the coolant in
the surge tank. If the tank empties,
turn the ignition off, carefully remove the pressure cap, refill to the indicated
line, replace the pressure cap, and
repeat steps 6.2
–6.6.
The fill and air removal process will
run for approximately 15 minutes.
Caution
If the pressure cap is not tightly
installed, coolant loss and engine
damage may occur. Be sure the cap
is properly and tightly secured.
Engine Overheating
The vehicle has an indicator to warn
of the engine overheating.
If the decision is made not to lift the
hood when this warning appears, get
service help right away. See Roadside
Service 0432.
If the decision is made to lift the
hood, make sure the vehicle is parked
on a level surface.
Then check to see if the engine
cooling fan is running. If the engine is
overheating, the fan should be