2020 CADILLAC CT6 air conditioning

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
2020 - CRC - 6/11/19
300 VEHICLE CARE
FusesUsage
1 –
2 – Fuses
Usage
3 –
4 – Fuses
Usage
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
22 Transmission auxiliary oil pump
cooling
23 –
24 Cabin heater pump

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
2020 - CRC - 6/11/19
302 VEHICLE CARE
RelaysUsage
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
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-13566829) -
2020 - CRC - 6/11/19
VEHICLE CARE 305
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-13566829) -
2020 - CRC - 6/11/19
306 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-13566829) -
2020 - CRC - 6/11/19
VEHICLE CARE 307
FusesUsage
F1 Auxiliary power outlet front console
F2 Visor
F3 Front blower
F4 Body control module 8
F5 Steering column switch module Fuses
Usage
F6 Electric steering column lock
F7 Glove box door
F8 Front heated seat module
F9 Sensing and diagnostic module Fuses
Usage
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 –
F22 –
F23 Central gateway module
F24 Center stack module/ Infotainment

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
2020 - CRC - 6/11/19
320 VEHICLE CARE
(1) Passenger (P-Metric) Tire:
The United States version of a
metric tire sizing system. The
letter“P”as the first character in
the tire size means a passenger
vehicle tire engineered to
standards set by the U.S. Tire and
Rim Association.
(2) Tire Width
:The three-digit
number indicates the tire section
width in millimeters from sidewall
to sidewall.
(3) Aspect Ratio
:A two-digit
number that indicates the tire
height-to-width measurements.
For example, if the tire size aspect
ratio is 60, as shown in item (3) of
the illustration, it would mean
that the tire's sidewall is
60 percent as high as it is wide.
(4) Construction Code
:A letter
code is used to indicate the type
of ply construction in the tire. The
letter “R”means radial ply
construction; the letter “D”means
diagonal or bias ply construction. (5) Rim Diameter
:Diameter of
the wheel in inches.
(6) Service Description
:These
characters represent the load
index and speed rating of the tire.
The load index represents the load
carrying capacity a tire is certified
to carry. The speed rating is the
maximum speed a tire is certified
to carry a load.
Tire Terminology and
Definitions
Air Pressure:The amount of air
inside the tire pressing outward
on each square inch of the tire.
Air pressure is expressed in kPa
(kilopascal) or psi (pounds per
square inch).
Accessory Weight
:The combined
weight of optional accessories.
Some examples of optional
accessories are automatic
transmission, power windows,
power seats, and air conditioning. Aspect Ratio
:The relationship of
a tire's height to its width.
Belt
:A rubber coated layer of
cords between the plies and the
tread. Cords may be made from
steel or other reinforcing
materials.
Bead
:The tire bead contains steel
wires wrapped by steel cords that
hold the tire onto the rim.
Bias Ply Tire
:A pneumatic tire in
which the plies are laid at
alternate angles less than
90 degrees to the centerline of the
tread.
Cold Tire Pressure
:The amount
of air pressure in a tire, measured
in kPa (kilopascal) or psi (pounds
per square inch) before a tire has
built up heat from driving. See
Tire Pressure 0322.
Curb Weight
:The weight of a
motor vehicle with standard and
optional equipment including the

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
2020 - CRC - 6/11/19
SERVICE AND MAINTENANCE 359
Maintenance Schedule
Owner Checks and Services
Check the engine oil level. SeeEngine
Oil 0277.
Once a Month
. Check the tire inflation pressures.
See Tire Pressure 0322.
. Inspect the tires for wear. See Tire
Inspection 0329.
. Check the windshield washer fluid
level. See Washer Fluid 0289.
Engine Oil Change
When the CHANGE ENGINE OIL
SOON message displays, have the
engine oil and filter changed within
the next 1 000 km (600 mi). If driven
under the best conditions, the engine
oil life system may not indicate the
need for vehicle service for up to a
year. The engine oil and filter must be
changed at least once a year and the
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 System
0280.
Engine Air Filter Change
When the REPLACE AT NEXT OIL
CHANGE message displays, the engine
air filter should be replaced at the
next engine oil change. When the
REPLACE ENGINE AIR FILTER SOON
message displays, the engine air filter
should be replaced at the earliest
convenience. Reset the engine air
filter life system after the engine air
filter is replaced. See Engine Air Filter
Life System 0281.
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 Rotation0329.
. Check engine oil level and oil
life percentage. If needed,
change engine oil and filter,
and reset oil life system. See
Engine Oil 0277 and
Engine Oil Life System 0280.
. If equipped with the engine air
filter life system, 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 0281. If the vehicle is not
equipped with the engine air filter
life system, inspect the engine air
cleaner filter. See Engine Air
Cleaner/Filter 0282.
. Check engine coolant level. See
Cooling System 0284.
. Check windshield washer fluid
level. See Washer Fluid 0289.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
2020 - CRC - 6/11/19
SERVICE AND MAINTENANCE 361
Maintenance Schedule
Additional Required Services -
Normal12 000 km/7,500 mi
24 000 km/15,000 mi
36 000 km/22,500 mi
48 000 km/30,000 mi
60 000 km/37,500 mi
72 000 km/45,000 mi
84 000 km/52,500 mi
96 000 km/60,000 mi
108 000 km/67,500 mi
120 000 km/75,000 mi
132 000 km/82,500 mi
144 000 km/90,000 mi
156 000 km/97,500 mi
168 000 km/105,000 mi
180 000 km/112,500 mi
192 000 km/120,000 mi
204 000 km/127,500 mi
216 000 km/135,000 mi
228 000 km/142,500 mi
240 000 km/150,000 mi
Rotate tires, if recommended for the vehicle, and
perform Required Services. (1) Check engine oil level
and oil life percentage. Change engine oil and filter,
if needed. Check engine air filter life percentage and
status. Change engine air filter, if needed.
@ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @
Replace passenger compartment air filter. (2)@ @@@@@
Inspect evaporative control system. (3)@ @@
Replace spark plugs. Inspect spark plug wires and/or
boots. (4.2L Engine)@ @
Replace spark plugs. Inspect spark plug wires and/or
boots. (3.6L Engine)@
Change transfer case fluid. (4)@
Change rear axle fluid. (Except V-Series) (4)@
Change rear axle fluid. (V-Series Only) (4)@@@
Change front axle fluid 4WD. (4)@
Drain and fill engine cooling system. (5)@
Visually inspect accessory drive belts. (6)@
Replace brake fluid. (7)
Replace windshield wiper blades. (8)
@ @ @ @ @ @ @ @ @ @
Replace hood and/or body lift support gas struts. (9)@ @
Replace air conditioning desiccant. (10)