2018 CADILLAC CTS Cooling fan

Cadillac CTS/CTS-V Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
11349156) - 2018 - CRC - 9/29/17
270 VEHICLE CARE
3.6L V6 Engine (LF3)
1. Engine Coolant Surge Tankand Pressure Cap
2. Engine Cooling Fan (Out of View)
6.2L V8 Engine (LT4)
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.
{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.
See Maintenance Schedule 0339 and
Recommended Fluids and Lubricants
0 348.
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 0274.

Cadillac CTS/CTS-V Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
11349156) - 2018 - CRC - 9/29/17
VEHICLE CARE 273
1. Remove the coolant surge tankpressure cap from the top
chamber 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. Open the
surge tank service port cap to
the lower chamber. The service
port is behind the top chamber.
3. Fill the surge tank top chamberwith the proper mixture to the
bottom of the fill neck. The top
chamber needs to be completely
full. Fill the surge tank bottom
chamber through the service port
to approximately half.
4. With the coolant surge tank pressure cap off and the surge
tank service port cap open, start
the engine and let it run until
you can feel the upper radiator
hose getting hot. Watch out for
the engine cooling fan(s).
By this time, the coolant level
inside the coolant surge tank top
chamber may be lower. If the level is lower, add more of the
proper mixture to the surge tank
top chamber until the level
reaches the bottom of the
fill neck.
5. Replace the surge tank pressure cap tightly and close the surge
tank service port cap.
6. Check the level in the surge tank top and bottom chambers when
the cooling system has cooled
down. If the coolant is not at the
proper levels, repeat Steps 1–
6 and reinstall the pressure cap
and close the service port. If the
coolant still is not at the proper
levels 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.

Cadillac CTS/CTS-V Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
11349156) - 2018 - CRC - 9/29/17
274 VEHICLE CARE
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. SeeRoadside
Service 0361.
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 Steam Is Coming from the
Engine Compartment with No
Overheat Warning
(V-Series Only)
The V-Series hood vent is functional,
and will allow water from rain and car
washes to enter the engine
compartment and contact hot
surfaces. If steam is seen coming from
the hood vent with no accompanying
overheat warning, no action is
required.
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

Cadillac CTS/CTS-V Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
11349156) - 2018 - CRC - 9/29/17
288 VEHICLE CARE
FusesUsage
22 Driver motorized seat belt
26 –
27 –/Heated seat 2
28 –/Reverse lock out
29 Adaptive forward lighting, Automatic
headlamp leveling/
Pedestrian protection
30 –
31 Passenger window switch
32 –
33 Sunroof
34 Front wiper
35 Steering column lock
36 Rear bussed electrical center/Ignition
37 –/Malfunction
Indicator Lamp/
Ignition
38 Aeroshutter Fuses
Usage
39 O2 sensor/Emissions
40 Ignition coil even/O2 sensor
41 Ignition coil odd
42 Engine control module
43 –
44 –
45 Washer
48 Instrument panel/ Body/Ignition
49 Fuel system control module/Ignition
50 Heated steering wheel
51 Engine control module/Ignition
52 Transmission control module/Ignition
53 Coolant pump
55 – Fuses
Usage
56 Transmission control module
64 Adaptive headlamp leveling
65 Left HID headlamp
66 Right HID headlamp
67 Left/Right high-beam headlamp
68 Headlamp leveling motor
69 Horn
71 Cooling fan
72 Starter 2
73 Brake vacuum pump
74 Starter 1
75 Air conditioning clutch
76 –
Relays Usage
8 Headlamp washer
23 Wiper control