2023 CADILLAC CT4 manual transmission

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/10/22
362 Driving and Operating
transmission in P (Park) for a
few minutes before turning
the engine off. If the overheat
warning comes on, see Engine
Overheating0391.
Parking on Hills
{Warning
To prevent serious injury or
death, always park your
vehicle and trailer on a level
surface when possible.
When parking your vehicle and
your trailer on a hill: 1. Press the brake pedal, but do not shift into P (Park)
yet. Turn the wheels into
the curb if facing downhill
or into traffic if facing
uphill.
2. Have someone place chocks under the trailer
wheels. 3. When the wheel chocks
are in place, gradually
release the brake pedal to
allow the chocks to absorb
the load of the trailer.
4. Reapply the brake pedal. Then apply the parking
brake and shift into
P (Park).
5. Release the brake pedal.
Leaving After Parking on
a Hill
1. Apply and hold the brake pedal.
.Start the engine.
.Shift into the
desired gear.
.Release the parking
brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the
chocks.
Maintenance when Trailer
Towing
The vehicle needs service
more often when used to tow
trailers. See Maintenance
Schedule 0469. It is especially
important to check the
automatic transmission fluid,
engine oil, axle lubricant, belts,
cooling system, and brake
system before and during
each trip.
Check periodically that all nuts
and bolts on the trailer hitch
are tight.
Engine Cooling when
Trailer Towing
The cooling system may
temporarily overheat during
severe operating conditions.
See Engine Overheating 0391.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
368 Vehicle Care
Vehicle Care
General Information
General Information . . . . . . 369
California PerchlorateMaterials
Requirements . . . . . . . . . . . . . 370
Accessories and Modifications . . . . . . . . . . . . . 370
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . 370
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . 371
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . 373
Engine Oil . . . . . . . . . . . . . . . . . . . . 378
Engine Oil Life System . . . 381
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 382
Manual Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 382
Hydraulic Clutch . . . . . . . . . . . 383
Engine Air Filter Life System . . . . . . . . . . . . . . . . . . . . . . 383
Engine Air Cleaner/ Filter . . . . . . . . . . . . . . . . . . . . . . . . . 384
Cooling System . . . . . . . . . . . . 386
Engine Overheating . . . . . . . 391 Washer Fluid . . . . . . . . . . . . . . . . 393
Brakes . . . . . . . . . . . . . . . . . . . . . . . . 393
Brake Pad Life System (If
Equipped) . . . . . . . . . . . . . . . . . . 396
Brake Fluid . . . . . . . . . . . . . . . . . . 398
Battery - North
America . . . . . . . . . . . . . . . . . . . . . 399
All-Wheel Drive . . . . . . . . . . . . 400
Park Brake and P (Park) Mechanism Check . . . . . . . 400
Wiper Blade Replacement . . . . . . . . . . . . . . 401
Windshield Replacement . . . . . . . . . . . . . . 401
Gas Strut(s) . . . . . . . . . . . . . . . . . 402
Headlamp Aiming
Front Headlamp Aiming . . . . . . . . . . . . . . . . . . . . . . . 403
Bulb Replacement
Bulb Replacement . . . . . . . . 403
Halogen Bulbs . . . . . . . . . . . . . . 403
High Intensity Discharge(HID) Lighting . . . . . . . . . . . . . 403
LED Lighting . . . . . . . . . . . . . . . . 403
Front Turn Signal Lamps . . . . . . . . . . . . . . . . . . . . . . . 404
Electrical System
Electrical SystemOverload . . . . . . . . . . . . . . . . . . . 404
Fuses and Circuit Breakers . . . . . . . . . . . . . . . . . . . 406
Engine Compartment
Fuse Block . . . . . . . . . . . . . . . . . 407
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 409
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . . . 411
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . 413
All-Season Tires . . . . . . . . . . . . 414
Winter Tires . . . . . . . . . . . . . . . . . 414
Run-Flat Tires . . . . . . . . . . . . . . . 415
Self-Sealing Tires . . . . . . . . . . 415
Low-Profile Tires . . . . . . . . . . 416
Summer Tires . . . . . . . . . . . . . . . 416
Tire Sidewall Labeling . . . . 417
Tire Designations . . . . . . . . . . 418
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . . . 419
Tire Pressure . . . . . . . . . . . . . . . 422
Tire Pressure for High-Speed
Operation . . . . . . . . . . . . . . . . . . 423
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . . . . 424

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
382 Vehicle Care
confirmation message
displays, select YES. The
oil life will change to 100%.
Be careful not to reset the
oil life display accidentally
at any time other than
after the oil is changed.
It cannot be reset
accurately until the next oil
change.
The oil life system can also be
reset as follows: 1. Using the DIC buttons, display REMAINING OIL
LIFE on the DIC. See Driver
Information Center (DIC)
(Base Level) 0129 or
Driver Information Center
(DIC) (Uplevel) 0132.
2. Fully press and release the accelerator pedal three
times within five seconds.
If the CHANGE ENGINE
OIL SOON message is not
on, the system is reset.
The system is reset when the
CHANGE ENGINE OIL SOON
message is off. If the CHANGE ENGINE OIL
SOON message comes back
on when the vehicle is started,
the engine oil life system has
not been reset. Repeat the
procedure.
Automatic
Transmission Fluid
How to Check Automatic
Transmission Fluid
It is not necessary to check
the transmission fluid level.
A transmission fluid leak is the
only reason for fluid loss. If a
leak occurs, take the vehicle to
your dealer and have it
repaired as soon as possible.
The vehicle is not equipped
with a transmission fluid level
dipstick. There is a special
procedure for checking and
changing the transmission
fluid. Because this procedure
is difficult, this should be done
at the dealer. Contact your
dealer for additional
information.
Caution
Use of the incorrect
automatic transmission fluid
may damage the vehicle, and
the damage may not be
covered by the vehicle
warranty. Always use the
correct automatic
transmission fluid. See
Recommended Fluids and
Lubricants
0474.
Change the fluid and filter at
the intervals listed in
Maintenance Schedule 0469,
and be sure to use the fluid
listed in Recommended Fluids
and Lubricants 0474.
Manual Transmission
Fluid
It is not necessary to check
the manual transmission fluid
level. A transmission fluid leak
is the only reason for fluid
loss. If a leak occurs, take the
vehicle to your dealer and
have it repaired as soon as

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 383
possible. See Recommended
Fluids and Lubricants0474
for the proper fluid to use.
Hydraulic Clutch
For vehicles with a manual
transmission, it is not
necessary to regularly check
brake/clutch fluid unless there
is a leak suspected. Adding
fluid will not correct a leak.
A fluid loss in this system
could indicate a problem. Have
the system inspected and
repaired.
When to Check and What
to Use
The brake/hydraulic clutch
fluid reservoir cap has this
symbol on it. See Engine
Compartment Overview 0373
for reservoir location. The common hydraulic clutch
and brake master cylinder fluid
reservoir is filled with brake
fluid as indicated on the
reservoir cap. See Brake Fluid
0
398 for brake fluid to use.
How to Check and Add
Fluid
Visually check the brake/
clutch fluid reservoir to make
sure the fluid level is at the
MIN (minimum) line on the side
of the reservoir. The brake/
hydraulic clutch fluid system
should be closed and sealed.
Do not remove the cap to
check the fluid level or to
top-off the fluid level. Remove
the cap only when necessary
to add the proper fluid until
the level reaches the MIN line.
Engine Air Filter Life
System
This feature provides the
engine air filter’s remaining life
and best timing for a change.
The timing to change an engine air filter depends on
driving and environmental
conditions.
When to Change the
Engine Air Filter
When the Driver Information
Center (DIC) displays a
message to replace the engine
air filter at the next oil change,
follow this timing.
When the DIC displays a
message to replace the engine
air filter soon, replace the
engine air filter at the earliest
convenience.
The system must be reset
after the engine air filter is
changed.
If the DIC displays a message
to check the engine air filter
system, see your dealer.
How to Reset the Engine
Air Filter Life System
To reset:
1. Place the vehicle in P (Park).

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
398 Vehicle Care
Brake Fluid
The brake/clutch master
cylinder reservoir is filled with
GM approved DOT 4 brake
fluid as indicated on the
reservoir cap. See Engine
Compartment Overview0373
for the location of the
reservoir.
Checking Brake Fluid
Place the vehicle in P (Park) or
Neutral with the parking brake
applied if equipped with a
manual transmission. On a
level surface, the brake fluid
level should be between the
minimum and maximum marks
on the brake fluid reservoir. There are only two reasons
why the brake fluid level in the
reservoir may go down:
.Normal brake lining wear.
When new linings are
installed, the fluid level goes
back up.
.A fluid leak in the brake/
clutch hydraulic system.
Have the brake/clutch
hydraulic system fixed. With
a leak, the brakes will not
work well.
Always clean the brake fluid
reservoir cap and the area
around the cap before
removing it.
Do not top off the brake/
clutch fluid. Adding fluid does
not correct a leak. If fluid is
added when the linings are
worn, there will be too much
fluid when new brake linings
are installed. Add or remove
fluid, as necessary, only when
work is done on the brake/
clutch hydraulic system.
{Warning
If too much brake fluid is
added, it can spill on the
engine and burn, if the
engine is hot enough. You or
others could be burned, and
the vehicle could be
damaged. Add brake fluid
only when work is done on
the brake/clutch hydraulic
system.
When the brake/clutch fluid
falls to a low level, the brake
warning light comes on. See
Brake System Warning Light
0 120.
Brake fluid absorbs water over
time which degrades the
effectiveness of the brake
fluid. Replace brake fluid at the
specified intervals to prevent
increased stopping distance.
See Maintenance Schedule
0 469.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
400 Vehicle Care
Vehicle Storage
{Warning
Batteries have acid that can
burn you and gas that can
explode. You can be badly
hurt if you are not careful.
See Jump Starting - North
America0447 for tips on
working around a battery
without getting hurt.
Infrequent Usage: Remove the
black, negative (−) cable from
the battery to keep the
battery from running down.
Extended Storage: Remove
the black, negative (−) cable
from the battery or use a
battery trickle charger.
All-Wheel Drive
If the vehicle is equipped with
All-Wheel-Drive (AWD), this is
an additional system that
needs lubrication.
Transfer Case
Under normal driving
conditions, transfer case fluid
does not require maintenance
unless there is a fluid leak or
unusual noise. If required, have
the transfer case serviced by
your dealer.
Park Brake and
P (Park) Mechanism
Check
{Warning
When you are doing this
check, the vehicle could
begin to move. You or
others could be injured and
property could be damaged.
Make sure there is room in
front of the vehicle in case it
begins to roll. Be ready to
apply the regular brake at
once should the vehicle
begin to move. Park on a fairly steep hill, with
the vehicle facing downhill.
Keeping your foot on the
regular brake, set the parking
brake.
.To check the parking brake's
holding ability: With the
engine running and the
transmission in N (Neutral),
slowly remove foot pressure
from the regular brake pedal.
Do this until the vehicle is
held by the parking
brake only.
.Automatic transmission
vehicles only: To check the
P (Park) mechanism's holding
ability: With the engine
running, shift to P (Park).
Then release the parking
brake followed by the
regular brake.
Contact your dealer if service
is required.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
408 Vehicle Care
Fuses Usage
1 Long Range RadarFront Sensor
2 Park/Daytime Running Lamps
3 Exterior Lighting Module 4
4 Exterior Lighting Module 7
5 Headlamp Level
6 –
Fuses Usage
7 Electronic Brake
Control Module
8 Washer Pump
9 –
10 –
11 –
12 Horn
13 Front Wiper
Fuses Usage
14 Exterior Lighting Module 6
15 Exterior Lighting Module 1
16 Exterior Lighting Module 5
17 Exterior Lighting Module 3
18 Aero Shutter
19 –
20 –
21 Virtual Key System/ Power Sounder
Module
22 Engine Control Module Battery
23 Transmission Control Module
24 Active Engine Mount
25 –
26 Engine Control Module
27 Injectors/Ignition 2
28 Charged Air Cooler/ Not Used
29 Transmission Aux Oil Pump/Transmission
Reverse Lock Out

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 411
Fuses Usage
29–
30 –
31 Headlamp Level
32 –
33 Body Ignition/IP Ignition
34 Exhaust Valve
35 Transmission Control Module Ignition/
Engine Control Module
Ignition/Shift Ignition/
Brake Ignition
36 Shift Module 37 Body Control Module 1/Electronic
Park Brake Switch
38 Center Stack Module
39 Steering Wheel Controls
40 Body Control Module 2
41 Body Control Module 3
42 Body Control Module 4
Circuit
Breakers Usage
CB1 Auxiliary Power
Outlet 1
CB2 Auxiliary Power Outlet 2
Relays Usage
1 Run After Park/Accessory
2 Run Crank
3 –
4 –
5 –
Rear Compartment
Fuse Block
The rear compartment fuse
block is behind a cover on the
driver side of the rear
compartment.
The vehicle may not be
equipped with all of the fuses,
relays, and features shown.