ignition CADILLAC CT4 2023 Workshop Manual

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 391
2. Add coolant through thesurge tank until it is visible
through the air bleeder.
3. Replace the cooling system air bleeder cap.
4. Add coolant to the indicated line on the
surge tank.
5. Replace the pressure cap on the surge tank.
6. Activate the service feature:
6.1. Connect the vehicle to a battery charger.
6.2.Turn the ignition to Service Mode. See
Ignition Positions 0261.
6.3.Turn off the air conditioning.
6.4.Set the parking brake.
6.5.At the same time, press the accelerator and the
brake pedal for
two seconds, then
release. 6.6.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, carefully remove
the pressure cap, refill
to the indicated line,
replace the pressure
cap, and repeat steps
6.2 –6.6.
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 6.2 –6.6.
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.
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
Assistance Program 0487.
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.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 397
When the ignition is turned on
after new pads and wear
sensors are installed, a
message will display. Follow
the prompts to reset the
system.
The brake pad life system can
also be manually reset:1. Display Brake Pad Life on the DIC. See Driver
Information Center (DIC)
(Base Level) 0129 or
Driver Information Center
(DIC) (Uplevel) 0132.
2. Select the Brake Pad Life menu.
3. Select front or rear pads as appropriate.
4. Select YES on the confirmation message.
Repeat for the pads on the
other axle if they were also
replaced.How to Disable the Brake
Pad Life System
The brake pad life system can
be turned off. This may be
necessary if aftermarket brake
pads without wear sensors
are installed. When the system
is turned off, the front and
rear brake pad
life percentages will not
display. However, the built-in
wear indicators that make a
high-pitched warning sound
when the brake pads are worn
can still determine when the
pads should be replaced. See
Brakes 0393.
To turn off the brake pad life
system: 1. Display Brake Pad Life on the DIC. See Driver
Information Center (DIC)
(Base Level) 0129 or
Driver Information Center
(DIC) (Uplevel) 0132.
2. Select the Brake Pad Life menu.
3. Select DISABLE. To turn the brake pad life
system back on, follow the
above steps but select
ENABLE in Step 2.
Brake Pad Sensor System
(V-Series Blackwing)
The V-Series Blackwing has
electronic brake pad wear
sensors, when the brake pads
need to be replaced, a
message displays in the Driver
Information Center (DIC).
When the message displays,
install new brake pads and
brake pad wear sensors on
the vehicle.
When the ignition is turned on
after new brake pads and
brake pad wear sensors are
installed, the message should
no longer display.
The brake pad sensor system
can only be reset by replacing
the brake pads and brake pad
wear sensors.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 405
Replacing a Blown Fuse
1. Turn off the ignition.
2. Locate the fuse puller inthe engine compartment
fuse block.
3. Use the fuse puller toremove the fuse from the
top or side, as shown
above.
4. If the fuse must be replaced immediately,
borrow a replacement fuse
with the same amperage
from the fuse block.
Choose a vehicle feature
that is not needed to
safely operate the vehicle.
Repeat Steps 2-3.

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 409
Fuses Usage
30 Injectors/Ignition 131 Emissions 1
32 Emissions 2
33 Starter Solenoid
34 –
35 –
36 Starter Pinion/ Not Used
37 AC Clutch
38 –
39 –
40 –
41 –
42 Water Pump/ Not Used
43 –
44 –
Relays Usage
47–
48 Front Wiper Speed/ Not Used
49 Front Wiper Control 51 –
Relays Usage
52 Engine Control
Module
53 Starter Solenoid
54 Starter Pinion/ Not Used
55 –
57 AC Clutch
58 –
Instrument Panel
Fuse Block
The instrument panel fuse
block is in the end of the driver
side of the instrument panel.
To access the fuses, remove
the end panel by gently prying
with a plastic tool near each
clip, beginning at the point
shown.
To install the end cover, insert
the tabs on the back of the
cover into the slots in the
instrument panel at the points
shown. Align the clips with the
slots in the instrument panel,
and press the cover into place.
The vehicle may not be
equipped with all of the fuses
and relays shown.

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.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
426 Vehicle Care
transmit the tire pressure
readings to a receiver located
in the vehicle.
When a low tire pressure
condition is detected, the
TPMS illuminates the low tire
pressure warning light located
on the instrument cluster.
If the warning light comes on,
stop as soon as possible and
inflate the tires to the
recommended pressure
shown on the Tire and
Loading Information label. See
Vehicle Load Limits0255.
A message to check the
pressure in a specific tire
displays in the Driver
Information Center (DIC). The
low tire pressure warning light
and the DIC warning message
come on at each ignition cycle
until the tires are inflated to the correct inflation pressure.
Using the DIC, tire pressure
levels can be viewed. For
additional information and
details about the DIC
operation and displays see
Driver Information Center
(DIC) (Base Level)
0129 or
Driver Information Center
(DIC) (Uplevel) 0132.
The low tire pressure warning
light may come on in cool
weather when the vehicle is
first started, and then turn off
as the vehicle is driven. This
could be an early indicator
that the air pressure is getting
low and needs to be inflated to
the proper pressure.
A Tire and Loading
Information label, attached to
your vehicle, shows the size of
the original equipment tires
and the correct inflation
pressure for the tires when
they are cold. See Vehicle
Load Limits 0255, for an
example of the Tire and Loading Information label and
its location. Also see Tire
Pressure
0422.
The TPMS can warn about a
low tire pressure condition but
it does not replace normal tire
maintenance. See Tire
Inspection 0429, Tire Rotation
0 429, and Tires 0413.Caution
Tire sealant materials are
not all the same.
A non-approved tire sealant
could damage the TPMS
sensors. TPMS sensor
damage caused by using an
incorrect tire sealant is not
covered by the vehicle
warranty. Always use only
the GM approved tire
sealant available through
your dealer or included in
the vehicle.
Factory-installed Tire Inflator
Kits use a GM-approved liquid
tire sealant. Using
non-approved tire sealants

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 427
could damage the TPMS
sensors. See Tire Sealant and
Compressor Kit0439 for
information regarding the
inflator kit materials and
instructions.
TPMS Malfunction Light
and Message
The TPMS will not function
properly if one or more of the
TPMS sensors are missing or
inoperable. When the system
detects a malfunction, the low
tire pressure warning light
flashes for about one minute
and then stays on for the
remainder of the ignition cycle.
A DIC warning message also
displays. The malfunction light
and DIC warning message
come on at each ignition cycle
until the problem is corrected.
Some of the conditions that
can cause these to come
on are:
.One of the road tires has
been replaced with the
spare tire. The spare tire
does not have a TPMS sensor. The malfunction light
and DIC message should go
off after the road tire is
replaced and the sensor
matching process is
performed successfully. See
“TPMS Sensor Matching
Process”
later in this section.
.The TPMS sensor matching
process was not done or not
completed successfully after
rotating the tires. The
malfunction light and the DIC
message should go off after
successfully completing the
sensor matching process.
See "TPMS Sensor Matching
Process" later in this section.
.One or more TPMS sensors
are missing or damaged. The
malfunction light and the DIC
message should go off when
the TPMS sensors are
installed and the sensor
matching process is
performed successfully. See
your dealer for service.
.Replacement tires or wheels
do not match the original
equipment tires or wheels. Tires and wheels other than
those recommended could
prevent the TPMS from
functioning properly. See
Buying New Tires
0432.
.Operating electronic devices
or being near facilities using
radio wave frequencies
similar to the TPMS could
cause the TPMS sensors to
malfunction.
If the TPMS is not functioning
properly it cannot detect or
signal a low tire pressure
condition. See your dealer for
service if the TPMS
malfunction light and DIC
message come on and stay on.
Tire Fill Alert (If Equipped)
This feature provides visual
and audible alerts outside the
vehicle to help when inflating
an underinflated tire to the
recommended cold tire
pressure.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 449
4. Turn the ignition off. Turnoff all lights and
accessories in both
vehicles, except the hazard
warning flashers if needed.
{Warning
An electric fan can start up
even when the engine is not
running and can injure you.
Keep hands, clothing, and
tools away from any
underhood electric fan.
{Warning
Using a match near a
battery can cause battery
gas to explode. People have
been hurt doing this, and
some have been blinded.
Use a flashlight if you need
more light.
Battery fluid contains acid
that can burn you. Do not
get it on you. If you
accidentally get it in your
(Continued)
Warning (Continued)
eyes or on your skin, flush
the place with water and get
medical help immediately.
{Warning
Fans or other moving engine
parts can injure you badly.
Keep your hands away from
moving parts once the
engine is running.
5. Connect one end of the red positive (+) cable to the
remote positive (+)
terminal on the discharged
battery.
6. Connect the other end of the red positive (+) cable to
the positive (+) terminal of
the good battery.
7. Connect one end of the black negative (–) cable to
the negative (–) terminal of
the good battery. Do not let the other end
touch anything until the
next step. The other end of
the negative (–) cable does
not go to the dead battery.
It goes to a heavy,
unpainted metal
engine part.
8. Connect the other end of the black negative (–) cable
to the negative (–)
grounding point for the
discharged battery.
9. Start the engine in the vehicle with the good
battery and run the engine
at idle speed for at least
four minutes.
10. Try to start the vehicle that had the dead battery.
If it will not start after a
few tries, it probably needs
service.
Jumper Cable Removal
Reverse the sequence exactly
when removing the jumper
cables.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Service and Maintenance 473
Exterior Lights
.Visual inspection
Windshield and Wipers
.Visual inspection
Battery
.Battery visual inspection
.Battery test results
.Battery cables and
connections
Systems, Fluids, and
Visible Leak Inspection
.Engine oil
.Transmission
.Drive axle
.Transfer case
.Engine cooling system
.Power steering, if equipped
.Fuel system
.Windshield washer fluid
Tire Inspection
.Tire pressure, tread depth,
and wear
.Rotation, if applicable
.Alignment check, optional
.Reset tire pressure monitor
.Check tire sealant expiration
date, if equipped
.Check spare tire, if equipped
Brakes
.Check brake system
Visible and Functional
Inspections
.Seat belt components
.Exhaust system
.Accelerator pedal
.Passenger compartment air
filter, if equipped
.Engine air filter
.Hoses
.Belts
.Shocks and struts
.Steering components
.Axle boots or driveshaft and
u-joints
.Compartment lift struts,
if equipped
.Floor mats secured, no
interference with pedals
.Horn
.Ignition lock, if equipped
.Starter switch
.Evaporative control system
Lubricate
.Chassis components
Special Application
Services
.Severe Commercial Use
Vehicles Only: Lubricate
chassis components every
oil change.
.Have underbody flushing
service performed. See
"Underbody Maintenance" in
Exterior Care 0455.