
Cadillac CT5 Owner Manual (GMNA-Localizing-U.S./Canada-14584312) -
2021 - CRC - 11/23/20
VEHICLE CARE 319
2. Press and hold the thumbwheel onthe steering wheel. When the
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) 0113 or
Driver Information Center (DIC)
(Uplevel) 0116.
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
0
392.
Change the fluid and filter at the
intervals listed in Maintenance
Schedule 0383, and be sure to use the
fluid listed in Recommended Fluids and
Lubricants 0392.
Engine Air Filter Life
System
If equipped, 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.

Cadillac CT5 Owner Manual (GMNA-Localizing-U.S./Canada-14584312) -
2021 - CRC - 11/23/20
320 VEHICLE CARE
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).
2. Display the Air Filter Life on the DIC. See Driver Information Center
(DIC) (Base Level) 0113 or
Driver Information Center (DIC)
(Uplevel) 0116. 3. Press
Ton the steering wheel,
or press the trip odometer reset
stem if the vehicle does not have
DIC controls, to move to the Reset/
Disable display area. Select Reset,
then press the thumbwheel or
press the reset stem for several
seconds.
4. Press the thumbwheel or the reset stem to confirm the reset.
Engine Air Cleaner/Filter
The engine air cleaner/filter is in the
engine compartment on the passenger
side of the vehicle for the 2.0L L4
engine, and in the center of the engine
compartment for the 3.0L V6 engine.
See Engine Compartment Overview
0 313.
When to Inspect the Engine Air
Cleaner/Filter
.For intervals on changing and
inspecting the engine air filter, see
break="2" Maintenance Schedule
0 383.
.If equipped with Engine Air Filter
Life System, see Engine Air Filter Life
System 0319.
.If driving in very dusty areas, follow
the engine air filter inspecting and
changing intervals, see Maintenance
Schedule 0383.
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.

Cadillac CT5 Owner Manual (GMNA-Localizing-U.S./Canada-14584312) -
2021 - CRC - 11/23/20
SERVICE AND MAINTENANCE 383
Maintenance Schedule
Owner Checks and Services
Check the engine oil level. SeeEngine
Oil 0316.
Once a Month
.Check the tire inflation pressures.
See Tire Pressure 0349.
.Inspect the tires for wear. See Tire
Inspection 0355.
.Check the windshield washer fluid
level. See Washer Fluid 0327.
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
0318.
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 Rotation0355.
.Check engine oil level and oil
life percentage. If needed, change
engine oil and filter, and reset oil
life system. See Engine Oil0316 and
Engine Oil Life System 0318.
.If equipped, 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 0319.
If the vehicle is not equipped with
the engine air filter life system,
inspect the engine air cleaner filter.
See Engine Air Cleaner/Filter 0320.
.Check engine coolant level. See
Cooling System 0322.
.Check windshield washer fluid level.
See Washer Fluid 0327.
.Check tire inflation pressures. See
Tire Pressure 0349.
.Inspect tire wear. See Tire Inspection
0 355.
.Visually check for fluid leaks.
.Inspect brake system. See Exterior
Care 0372.
.Visually inspect steering,
suspension, and chassis
components for damage, including
cracks or tears in the rubber boots,
loose or missing parts, or signs of
wear at least once a year. See
Exterior Care 0372.

Cadillac CT5 Owner Manual (GMNA-Localizing-U.S./Canada-14584312) -
2021 - CRC - 11/23/20
SERVICE AND MAINTENANCE 385
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.
If equipped, check engine air filter life percentage
and status. Change engine air filter, if needed.
@ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @
Replace passenger compartment air filter. (2)@ @@@@@
If the vehicle is not equipped with the engine air
filter life system, replace engine air cleaner filter. (3)@ @@
Inspect evaporative control system. (4)@@@
Replace spark plugs. Inspect spark plug wires and/or
boots.@ @
Change transfer case fluid, if equipped with
AWD. (5)@
Change rear axle fluid, if equipped with limited slip
differential. (5)@@@
Change rear axle fluid, without limited slip
differential. (5)@
Change front axle fluid, if equipped with AWD. (5)@
Drain and fill engine cooling system. (6)@
Visually inspect accessory drive belts. (7)@
Replace brake fluid. (8)
Replace windshield wiper blades. (9)
@ @ @ @ @ @ @ @ @ @
Replace hood and/or body lift support gas
struts. (10)@ @
Replace air conditioning desiccant. (11)

Cadillac CT5 Owner Manual (GMNA-Localizing-U.S./Canada-14584312) -
2021 - CRC - 11/23/20
386 SERVICE AND MAINTENANCE
Footnotes—Maintenance Schedule
Additional Required Services -
Normal
(1) Vehicles with different size front
and rear tires do not have tire
rotation. See Tire Rotation0355.
(2) Or every two years, whichever
comes first. More frequent passenger
compartment air filter replacement
may be needed if driving in areas with
heavy traffic, poor air quality, high
dust levels, or environmental
allergens. Passenger compartment air
filter replacement may also be needed
if there is reduced airf low, window
fogging, or odors. Your GM dealer can
help determine when to replace the
filter.
(3) Or every four years, whichever
comes first. If driving in dusty
conditions, inspect the filter at each
oil change or more often as needed.
See Engine Air Cleaner/Filter 0320.
(4) Visually check all fuel and vapor
lines and hoses for proper attachment,
connection, routing, and condition. (5)
Do not directly power wash the
transfer case and/or front/rear axle
output seals. High pressure water can
overcome the seals and contaminate
the transfer case fluid. Contaminated
fluid will decrease the life of the
transfer case and/or axles and should
be replaced.
(6) Or every five years, whichever
comes first. See Cooling System0322.
(7) Or every 10 years, whichever
comes first. Inspect for fraying,
excessive cracking, or damage; replace,
if needed.
(8) Replace brake fluid every five
years. See Brake Fluid 0329.
(9) Or every 12 months, whichever
comes first. See Wiper Blade
Replacement 0331.
(10) Or every 10 years, whichever
comes first. See Gas Strut(s)0332.
(11) Replace air conditioning
desiccant every seven years.

Cadillac CT5 Owner Manual (GMNA-Localizing-U.S./Canada-14584312) -
2021 - CRC - 11/23/20
SERVICE AND MAINTENANCE 387
Maintenance Schedule
Additional Required Services -
Severe12 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.
If equipped, check engine air filter life percentage
and status. Change engine air filter, if needed.
@ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @
Replace passenger compartment air filter. (2)@ @@@@@
If the vehicle is not equipped with the engine air
filter life system, replace engine air cleaner filter. (3)@ @@
Inspect evaporative control system. (4)@@@
Replace spark plugs. Inspect spark plug wires and/or
boots.@ @
Change automatic transmission fluid and filter.@@@
Change transfer case fluid, if equipped with
AWD. (5)@@@
Change rear axle fluid, if equipped with limited slip
differential. (5)@@@
Change rear axle fluid, without limited slip
differential. (5)@ @
Change front axle fluid, if equipped with AWD. (5)@@@
Drain and fill engine cooling system. (6)@
Visually inspect accessory drive belts. (7)@
Replace brake fluid. (8)
Replace windshield wiper blades. (9)
@ @ @ @ @ @ @ @ @ @

Cadillac CT5 Owner Manual (GMNA-Localizing-U.S./Canada-14584312) -
2021 - CRC - 11/23/20
388 SERVICE AND MAINTENANCE
Maintenance Schedule
Additional Required Services -
Severe12 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
Replace hood and/or body lift support gas
struts. (10)@ @
Replace air conditioning desiccant. (11)
Footnotes—Maintenance Schedule
Additional Required Services -
Severe
(1) Vehicles with different size front
and rear tires do not have tire
rotation. See Tire Rotation0355.
(2) Or every two years, whichever
comes first. More frequent passenger
compartment air filter replacement
may be needed if driving in areas with
heavy traffic, poor air quality, high
dust levels, or environmental
allergens. Passenger compartment air
filter replacement may also be needed
if there is reduced airf low, window fogging, or odors. Your GM dealer can
help determine when to replace the
filter.
(3)
Or every four years, whichever
comes first. If driving in dusty
conditions, inspect the filter at each
oil change or more often as needed.
See Engine Air Cleaner/Filter 0320.
(4) Visually check all fuel and vapor
lines and hoses for proper attachment,
connection, routing, and condition.
(5) Do not directly power wash the
transfer case and/or front/rear axle
output seals. High pressure water can
overcome the seals and contaminate
the transfer case fluid. Contaminated fluid will decrease the life of the
transfer case and/or axles and should
be replaced.
(6)
Or every five years, whichever
comes first. See Cooling System0322.
(7) Or every 10 years, whichever
comes first. Inspect for fraying,
excessive cracking, or damage; replace,
if needed.
(8) Replace brake fluid every five
years. See Brake Fluid 0329.
(9) Or every 12 months, whichever
comes first. See Wiper Blade
Replacement 0331.

Cadillac CT5 Owner Manual (GMNA-Localizing-U.S./Canada-14584312) -
2021 - CRC - 11/23/20
INDEX 425
DoorAjar Light . . . . . . . . . . . . . . . . . . . . . . . . . 113
Delayed Locking . . . . . . . . . . . . . . . . . . . 17
Locks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Power Locks . . . . . . . . . . . . . . . . . . . . . . . . 17
Drive Belt Routing, Engine . . . . . . . . . 400
Drive Systems All-Wheel Drive . . . . . . . . . . . . . 237, 331
Driver Teen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 189
Driver Assistance Systems . . . . . . . . . 275
Driver Information
Center (DIC) . . . . . . . . . . . . . . . . . .113, 116
Driver Mode Control . . . . . . . . . . . . . . . . 242
Driver Mode Control Light . . . . . . . . . 109
Driving Assistance Systems . . . . . . . . . . . . . . . 285
Better Fuel Economy . . . . . . . . . . . . . 209
Characteristics andTowing Tips . . . . . . . . . . . . . . . . . . . . . 301
Competitive . . . . . . . . . . . . . . . . . . . . . . . 247
Defensive . . . . . . . . . . . . . . . . . . . . . . . . . . 210
Hill and Mountain Roads . . . . . . . . 217
If the Vehicle is Stuck . . . . . . . . . . . . 219
Impaired . . . . . . . . . . . . . . . . . . . . . . . . . . . 210
Loss of Control . . . . . . . . . . . . . . . . . . . . 212
Off-Road Recovery . . . . . . . . . . . . . . . . 212 Driving (cont'd)
Track Events and
Competitive . . . . . . . . . . . . . . . . . . . . . . 213
Vehicle Load Limits . . . . . . . . . . . . . . 219
Wet Roads . . . . . . . . . . . . . . . . . . . . . . . . . 217
Winter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 218
Dual Automatic Climate
Control System . . . . . . . . . . . . . . . . . . . . 202
E
Electric Brake Boost . . . . . . . . . . . . . . . . 237
Electric Parking Brake . . . . . . . . . . . . . . 238
Electric Parking Brake Light . . . . . . . 106
Electrical Equipment, Add-On . . . . . 307
Electrical SystemEngine Compartment FuseBlock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 335
Fuses and Circuit Breakers . . . . . . . 334
Instrument Panel Fuse Block . . . . 337
Overload . . . . . . . . . . . . . . . . . . . . . . . . . . . 334
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 340
Emergency OnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 415
Engine Air Cleaner/Filter . . . . . . . . . . . . . . . . . 320
Check Light (Malfunction
Indicator) . . . . . . . . . . . . . . . . . . . . . . . . 103 Engine (cont'd)
Compartment Overview . . . . . . . . . . 313
Coolant Temperature
Gauge . . . . . . . . . . . . . . . . . . . . . . 100, 101
Coolant Temperature Warning Light . . . . . . . . . . . . . . . . . . . 109
Cooling System . . . . . . . . . . . . . . . . . . . 322
Drive Belt Routing . . . . . . . . . . . . . . . . 400
Exhaust . . . . . . . . . . . . . . . . . . . . . . . . . . . . 231
Heater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 227
Oil Life System . . . . . . . . . . . . . . . . . . . . 318
Oil Pressure Light . . . . . . . . . . . . . . . . . 110
Overheating . . . . . . . . . . . . . . . . . . . . . . . 326
Power Messages . . . . . . . . . . . . . . . . . . 123
Running While Parked . . . . . . . . . . . 231
Starting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225
Engine Air Filter Life System . . . . . . 319
Entry Lighting . . . . . . . . . . . . . . . . . . . . . . 137
Equipment, Towing . . . . . . . . . . . . . . . . . 306
Event Data Recorders . . . . . . . . . . . . . . 412
Exit Lighting . . . . . . . . . . . . . . . . . . . . . . . . 138
Extended Parking . . . . . . . . . . . . . . . . . . . 230
Extender, Seat Belt . . . . . . . . . . . . . . . . . . 53
Exterior Lamp Controls . . . . . . . . . . . . 132
Exterior Lamps Off Reminder . . . . . . 134
Exterior Lighting Battery Saver . . . . 139