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320 VEHICLE CARE
{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
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
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
0 219.
3.3. Turn off the air conditioning.
3.4. Set the parking brake.
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VEHICLE CARE 321
3.5. At the same time, press theaccelerator 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.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
0 219.
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
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Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
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322 VEHICLE CARE
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 0403.
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 running. If it is not, do not continue
to run the engine. Have the vehicle
serviced.
Caution
Do not run the engine if there is a
leak in the engine cooling system.
This can cause a loss of all coolant
and can damage the system and
vehicle. Have any leaks fixed
right away.
If Steam Is Coming from the
Engine Compartment
{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.
If No Steam Is Coming from the
Engine Compartment
If an engine overheat warning is
displayed but no steam can be seen or
heard, the problem may not be too
serious. Sometimes the engine can get
a little too hot when the vehicle:
.Climbs a long hill on a hot day.
.Stops after high-speed driving.
.Idles for long periods in traffic.
If the overheat warning is displayed
with no sign of steam: 1. Turn the air conditioning off.
2. Turn the heater on to the highest temperature and to the highest fan
speed. Open the windows as
necessary.
3. When it is safe to do so, pull off the road, shift to P (Park) or
N (Neutral) and let the engine idle.
If the overheat warning no longer
displays, the vehicle can be driven.
Continue to drive the vehicle slowly
for about 10 minutes. Keep a safe
vehicle distance from the vehicle in
front. If the warning does not come
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SERVICE AND MAINTENANCE 381
oil life system must be reset. Your
trained dealer technician can perform
this work. If the engine oil life system
is reset accidentally, service the
vehicle within 5 000 km (3,000 mi)
since the last service. Reset the oil life
system when the oil is changed. See
Engine Oil Life System0314.
Air Conditioning Desiccant
(Replace Every Seven Years)
The air conditioning system requires
maintenance every seven years. This
service requires replacement of the
desiccant to help the longevity and
efficient operation of the air
conditioning system. This service can
be complex. See your dealer.
Tire Rotation and Required
Services Every 12 000 km
(7,500 mi)
Rotate the tires, if recommended for
the vehicle, and perform the following
services. See Tire Rotation0352.
.Check engine oil level and oil
life percentage. If needed, change
engine oil and filter, and reset oil
life system. See Engine Oil0312 and
Engine Oil Life System 0314.
.If equipped, check the air filter
life percentage. If necessary, replace
the engine air filter and reset the
engine air filter life system. See
Engine Air Filter Life System 0315.
If the vehicle is not equipped with
the engine air filter life system,
inspect the engine air cleaner filter.
See Engine Air Cleaner/Filter 0316.
.Check engine coolant level. See
Cooling System 0317.
.Check windshield washer fluid level.
See Washer Fluid 0323.
.Check tire inflation pressures. See
Tire Pressure 0346.
.Inspect tire wear. See Tire Inspection
0 352.
.Visually check for fluid leaks.
.Inspect brake system. See Exterior
Care 0370.
.Visually inspect steering,
suspension, and chassis
components for damage, including
cracks or tears in the rubber boots,
loose or missing parts, or signs of
wear at least once a year. See
Exterior Care 0370.
.Inspect power steering for proper
attachment, connections, binding,
leaks, cracks, chafing, etc.