2019 CADILLAC CT6 air conditioning

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-12533370) -
2019 - crc - 1/23/19
188 CLIMATE CONTROLS
atmosphere is harmful to the
environment and may also create
unsafe conditions based on inhalation,
combustion, frostbite, or other
health-based concerns.
The air conditioning system requires
periodic maintenance. See
Maintenance Schedule0383.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-12533370) -
2019 - crc - 1/23/19
VEHICLE CARE 311
1. Remove the coolant surge tankpressure 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 about
one-quarter of a turn. 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.
3. Fill the coolant surge tank with the proper mixture 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 coolant surge
tank until the level reaches the
indicated level mark.
5. Replace the pressure cap tightly.
6. Verify coolant level after the engine is shut off and the
coolant is cold. If necessary,
repeat coolant fill procedure
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.
2.0L L4 Engine Only - Automatic
Coolant Service Fill Instructions
If equipped, this feature assists in
filling and removing air from the
cooling system after service of
components or when coolant is added
after being too low.
To activate the fill and air removal
process:
1. With a cold system, add coolant to the COLD FILL mark on the
surge tank.
2. Replace the cap on the surge tank.
3. Connect the vehicle to a battery charger.
4. Turn the ignition to Service Mode. See Ignition Positions
0 201.
5. Turn off the air conditioning.
6. Set the parking brake.
7. At the same time, press the accelerator and the brake for
two seconds, then release.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-12533370) -
2019 - crc - 1/23/19
VEHICLE CARE 313
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 engine coolant temperature
gauge is no longer in the overheated
area or the engine coolant
temperature warning light no longer
displays, the vehicle can be driven. Continue to drive the vehicle slowly
for about 10 minutes. Keep a safe
distance from the vehicle in front.
If the warning does not come back on,
continue to drive normally and have
the cooling system checked for proper
fill and function.
If the warning continues, pull over,
stop, and park the vehicle right away.
If there is no sign of steam, idle the
engine for three minutes while parked.
If the warning is still displayed, turn
off the engine until it cools down.
Washer Fluid
What to Use
When windshield washer fluid is
needed, be sure to read the
manufacturer's instructions before
use. If operating the vehicle in an area
where the temperature may fall below
freezing, use a fluid that has sufficient
protection against freezing.
Adding Washer Fluid
Open the cap with the washer symbol
on it. Add washer fluid until the tank
is full. See
Engine Compartment
Overview 0292 for reservoir location.
Caution
.
Do not use washer fluid that
contains any type of water
repellent coating. This can
cause the wiper blades to
chatter or skip.
. Do not use engine coolant
(antifreeze) in the windshield
washer. It can damage the
windshield washer system
and paint.
(Continued)

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-12533370) -
2019 - crc - 1/23/19
324 VEHICLE CARE
FusesUsage
1 –
2 –
3 –
4 –
5 Transfer case control/Transmission
control module
ignition
6 –
7 Starter motor
8 Starter pinion
9 Horn
10 –
11 –
12 –
13 High-beam headlamps left/right
18 Right cornering LED
21 Air conditioning clutch

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-12533370) -
2019 - crc - 1/23/19
326 VEHICLE CARE
FusesUsage
69 –
70 –
71 Antilock brake system valve
72 –
73 –
Relays Usage
14 Air conditioning control
15 Starter motor
16 Starter pinion
17 Run/Crank
19 –
20 High-beam headlamp
25 Cabin heater pump
48 –
49 –
50 Engine control module
51 Wiper speed Relays
Usage
52 Wiper control
53 Headlamp control
65 –
4.2L Engine
The 4.2L engine has an underhood
fuse block on each side of the engine
compartment.
Driver Side Fuse Block
Lift the fuse block cover to access the
fuses.
The vehicle may not be equipped with
all of the fuses and relays shown.
Caution
Spilling liquid on any electrical
component on the vehicle may
damage it. Always keep the covers
on any electrical component.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-12533370) -
2019 - crc - 1/23/19
VEHICLE CARE 329
FusesUsage
F1 Electric brake control module–2
F2 –
F3 Headlamp/Daytime running lamps
F4 Right cornering LED
F5 – Fuses
Usage
F6 Front short range radar sensors
F7 Horn
F8 Air conditioning clutch
F9 –
F10 – Fuses
Usage
F11 Automatic headlamp leveling
F12 Starter motor
F13 Starter pinion
F14 –
F15 –
F16 –
F17 Cabin heater pump
F18 Transmission auxiliary oil pump
cooling
F19 Engine control module ignition
F20 Non walk
F21 Ignition coils –even/
Non walk –2
F22 Engine control module ignition –1
F23 Transfer case control module
F24 –
F25 Ignition coils –odd

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-12533370) -
2019 - crc - 1/23/19
330 VEHICLE CARE
FusesUsage
F26 Charge air coolant pump
F27 Engine control module ignition –2
F28 –
F29 –
Relays Usage
R1 Headlamp/Daytime running lamps
R2 Air conditioning control
R3 Starter motor
R4 Starter pinion
R5 Cabin heater pump
R6 Engine control module
R7 –
R8 –Instrument Panel Fuse
Block
The instrument panel fuse block is
behind the driver side instrument
panel storage compartment.
The storage compartment has a press
to open latch. To access the fuses,
open the compartment by pressing
and releasing near the top center
square.
Apply pressure to the two retaining
tabs on the sides of the compartment,
until the two retaining tabs clear the
sides of the instrument panel. Allow
the compartment to move downward,
and out of the way.
To reinstall the compartment, reverse
the steps.
The vehicle may not be equipped with
all of the fuses shown.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-12533370) -
2019 - crc - 1/23/19
VEHICLE CARE 331
FusesUsage
F1 Auxiliary power outlet front console
F2 Visor
F3 Front blower
F4 Body control module 8 Fuses
Usage
F5 Power steering column
F6 Electric steering column lock
F7 Glove box door
F8 Front heated seat module Fuses
Usage
F9 Sensing and diagnostic module
F10 Body control module 4
F11 Body control module 3
F12 Data link connector
F13 –
F14 Electronic shifter
F15 Front camera
F16 Display
F17 Heating, ventilation, and air conditioning
control
F18 OnStar
F19 –
F20 –
F21 Traction power inverter 2
F22 –
F23 Central gateway module