Cadillac CT5 Owner Manual (GMNA-Localizing-U.S./Canada-14584312) -
2021 - CRC - 11/23/20
VEHICLE CARE 325
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 too low.
To use the service feature:
1. With a cold system, add coolant tothe indicated line on the
surge tank.
2. Replace the pressure cap on the surge tank. To activate the service feature:
1. Connect the vehicle to a battery charger.
2. Turn the ignition on. See Ignition
Positions 0224.
3. Turn off the air conditioning.
4. Set the parking brake.
5. At the same time, press the accelerator and the brake pedal for
two seconds, then release.
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 2–6.
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 2–6.
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.
3.0L V6 Engine
1. 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. This will
allow any pressure still left to be
vented out the discharge hose.
2. Keep turning the pressure cap slowly and remove it.
Cadillac CT5 Owner Manual (GMNA-Localizing-U.S./Canada-14584312) -
2021 - CRC - 11/23/20
326 VEHICLE CARE
3. Fill the surge tank with the propermixture to the indicated
level mark.
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.
Watch out for the engine
cooling fan.
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
surge tank until the level reaches
the indicated level mark.
5. Replace the pressure cap tightly. 6. Check the level in the surge tank
after the engine is shut off and the
cooling system has cooled down.
If the coolant is not at the proper
level, repeat Steps 1–6. If the
coolant still is not at the proper
level when the system cools down
again, see your dealer.
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 0405.
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.
