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VEHICLE CARE 245
Caution (Continued)
transmission fluid. See
Recommended Fluids and Lubricants
0313.
Change the fluid and filter at the
intervals listed in Maintenance
Schedule 0303, and be sure to use the
fluid listed in Recommended Fluids and
Lubricants 0313.
Engine Air Cleaner/Filter
The engine air cleaner/filter is in the
engine compartment on the passenger
side of the vehicle. See Engine
Compartment Overview 0238.
When to Inspect the Engine Air
Cleaner/Filter
For intervals on inspecting and
replacing the engine air cleaner/filter,
see Maintenance Schedule 0303.
How to Inspect/Replace the
Engine Air Cleaner/Filter
Do not start the engine or have the
engine running with the engine air
cleaner/filter housing open. Before
removing the engine air cleaner/filter,
make sure that the engine air cleaner/
filter housing and nearby components
are free of dirt and debris.
Do not clean the engine air cleaner/
filter or components with water or
compressed air.
To inspect or replace the air cleaner/
filter:
2.0L L4 Engine Shown, 2.7L L4 Engine
Similar
1. Remove the five screws on top of the air cleaner/filter cover.
2. Lift the air/cleaner/filter cover away from the air cleaner/filter
housing.
3. Pull out the air cleaner/filter.
4. Inspect or replace the air cleaner/filter.
5. Reverse Steps 1–3 to reinstall the air cleaner/filter cover.
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256 VEHICLE CARE
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. .
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.
Wiper Blade Replacement
Windshield wiper blades should be
inspected for wear and cracking. See
Maintenance Schedule 0303.
Replacement blades come in different
types and are removed in different
ways. For proper type and length, see
Maintenance Replacement Parts 0314.
Caution
Allowing the wiper arm to touch
the windshield when no wiper blade
is installed could damage the
windshield. Any damage that occurs
would not be covered by the vehicle
warranty. Do not allow the wiper
arm to touch the windshield. To replace the windshield wiper blade:
1. Pull the windshield wiper assembly away from the
windshield.
2. Lift up on the latch in the middleof the wiper blade where the
wiper arm attaches.
3. With the latch open, pull the wiper blade down toward the
windshield far enough to release
it from the J-hooked end of the
wiper arm.
4. Remove the wiper blade.
5. Reverse Steps 1–3 for wiper blade replacement.
Page 263 of 356
Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
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262 VEHICLE CARE
FusesUsage
12 Horn
13 Front wiper
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 –
23 Transmission control module
24 Active engine mount
25 – Fuses
Usage
26 Engine control module
27 Injectors/Ignition 2
28 Charged air cooler
29 Transmission coolant pump
30 Injectors/Ignition 1
31 Emissions 1
32 Emissions 2
33 Starter solenoid
34 –
35 Coolant pump
36 Starter pinion
37 AC clutch
38 –
39 –
40 –
41 –
42 Water pump
43 – Fuses
Usage
44 –
Relays Usage
47 –
48 Front wiper speed
49 Front wiper control
51 –
52 Engine control module
53 Starter solenoid
54 Starter pinion
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.
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264 VEHICLE CARE
FusesUsage
2 HVAC blower
3 –
4 –
5 Theft deterrent/ Universal garage door
opener
6 –
7 Air quality ionizer
8 Heated steering wheel
9 –
10 Electronic steering column lock 1
11 –
12 –
13 –
14 –
15 –
16 –
17 –
18 Display/ Infotainment/USB Fuses
Usage
19 Airbag/Automatic occupant sensing/
Data link connection/
Wireless charging
module
20 Power steering column module/
Electronic steering
column lock 2
21 –
22 –
23 –
24 –
25 USB
26 –
27 –
28 –
29 –
30 –
31 Headlamp level
32 – Fuses
Usage
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
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272 VEHICLE CARE
Tire Designations
Tire Size
The example shows a typical
passenger vehicle tire size.
(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.
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VEHICLE CARE 289
2.0L L4 Engine Shown, 2.7L L4 EngineSimilar
1. Discharged Battery Remote
Positive Terminal
2. Discharged Battery Negative Grounding Point
3. Good Battery Negative Terminal
4. Good Battery Positive Terminal
The jump start positive terminal (4)
and negative post (3) are on the
battery of the vehicle providing the
jump start. The jump start remote positive
terminal (1) and the remote negative
grounding point (2) for the discharged
battery are on the passenger side of
the vehicle.
The positive jump start connection for
the discharged battery is under a
cover. Lift the cover to expose the
terminal.
1. Check the other vehicle. It must have a 12-volt battery with a
negative ground system.
Caution
If the other vehicle does not have a
12-volt system with a negative
ground, both vehicles can be
damaged. Only use a vehicle that
has a 12-volt system with a
negative ground for jump starting.
2. Position the two vehicles so that they are not touching. 3. Set the parking brake firmly and
put the shift lever in P (Park)
with an automatic transmission,
or Neutral with a manual
transmission.
Caution
If any accessories are left on or
plugged in during the jump starting
procedure, they could be damaged.
The repairs would not be covered
by the vehicle warranty. Whenever
possible, turn off or unplug all
accessories on either vehicle when
jump starting.
4. Turn the ignition off. Turn off all lights and accessories in both
vehicles, except the hazard
warning flashers if needed.
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VEHICLE CARE 291
Jumper Cable Removal
Reverse the sequence exactly when
removing the jumper cables.
After starting the disabled vehicle and
removing the jumper cables, allow it
to idle for several minutes.Towing the Vehicle
Caution
Incorrectly towing a disabled
vehicle may cause damage. The
damage would not be covered by
the vehicle warranty. Do not lash or
hook to suspension components.
Use the proper straps around the
tires to secure the vehicle. Do not
drag a locked wheel/tire. Use tire
skates or dollies under any locked
wheel/tire while loading the vehicle.
Do not use a sling type lift to tow
the vehicle. This could damage the
vehicle.
Front Tow Eye
Caution
Improper use of the tow eye can
damage the vehicle. If equipped, use
the tow eye to load a disabled
vehicle onto a flatbed tow truck
from a flat road surface, or to move
the vehicle a short distance. Use
caution and low speeds. The
transmission must be
in (N) Neutral when moving the
vehicle.
Page 306 of 356
Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
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SERVICE AND MAINTENANCE 305
.Lubricate body components. See
Exterior Care 0293.
. Check starter switch. See Starter
Switch Check 0255.
. Check parking brake and
automatic transmission park
mechanism. See Park Brake and
P (Park) Mechanism Check 0256. .
Check accelerator pedal for
damage, high effort, or binding.
Replace if needed.
. Visually inspect gas strut for signs
of wear, cracks, or other damage.
Check the hold open ability of the
strut. If the hold open is low,
service the gas strut. See Gas
Strut(s) 0257.
. Inspect sunroof track and seal,
if equipped. See Sunroof031.