2020 CADILLAC CT4 cooling

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
132 LIGHTING
charge. It then adjusts the voltage for
best performance and extended life of
the battery.
When the battery's state of charge is
low, the voltage is raised slightly to
quickly bring the charge back up.
When the state of charge is high, the
voltage is lowered slightly to prevent
overcharging. If the vehicle has a
voltmeter gauge or a voltage display
on the Driver Information Center
(DIC), you may see the voltage move
up or down. This is normal. If there is
a problem, an alert will be displayed.
The battery can be discharged at idle
if the electrical loads are very high.
This is true for all vehicles. This is
because the generator (alternator)
may not be spinning fast enough at
idle to produce all the power that is
needed for very high electrical loads.
A high electrical load occurs when
several of the following are on, such
as: headlamps, high beams, fog lamps,
rear window defogger, climate control
fan at high speed, heated seats, engine
cooling fans, and loads plugged into
accessory power outlets.EPM works to prevent excessive
discharge of the battery. It does this
by balancing the generator's output
and the vehicle's electrical needs.
It can increase engine idle speed to
generate more power, whenever
needed. It can temporarily reduce the
power demands of some accessories.
Normally, these actions occur in steps
or levels, without being noticeable. In
rare cases at the highest levels of
corrective action, this action may be
noticeable to the driver. If so, a DIC
message might be displayed. If a
battery message is displayed, it is
recommended that the driver reduce
the electrical loads as much as
possible. See
Driver Information Center
(DIC) 0109.
Battery Power Protection
The battery saver feature is designed
to protect the vehicle's battery.
If some interior lamps are left on and
the ignition is turned off, the battery
rundown protection system
automatically turns the lamp off after
some time.
Exterior Lighting Battery
Saver
The exterior lamps turn off about
10 minutes after the ignition is turned
off, if the parking lamps or headlamps
have been manually left on. This
protects against draining the battery.
To restart the 10-minute timer, turn
the exterior lamp control to the
O
position and then back to the;or
2position.
To keep the lamps on for more than
10 minutes, the ignition must be on or
in ACC/ACCESSORY.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
134 CLIMATE CONTROLS
Climate Controls
Climate Control Systems
Dual Automatic Climate ControlSystem . . . . . . . . . . . . . . . . . . . . . . . . . . 134
Air Vents
Air Vents . . . . . . . . . . . . . . . . . . . . . . . . . . 139
Maintenance
Passenger Compartment AirFilter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
Climate Control Systems
Dual Automatic Climate Control System
The climate control buttons on the center stack and on the climate control
display are used to adjust the heating, cooling, and ventilation system.
Center Stack Climate Controls
1. ON/OFF (Power)
2. AUTO (Automatic Operation)
3. Air Delivery Mode Control
4. Driver Temperature Controls
5. Fan Control
6. Passenger Temperature Controls 7. A/C (Air Conditioning)
8. Recirculation
9. SYNC (Synchronized
Temperature)
10. Defrost
11. Rear Window Defogger

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
DRIVING AND OPERATING 147
{Warning
Prior to each track event and again
before returning to public roads,
tighten the wheel nuts with a
torque wrench to the proper torque
specification. Wheel nuts that are
improperly or incorrectly tightened
can cause the wheels to become
loose or come off, resulting in a
crash. SeeCapacities and
Specifications 0318 for wheel nut
torque specifications.
Caution
Low oil levels can damage the
engine. If using the vehicle for
competitive driving, the engine may
use more oil than it would with
normal use. Check the oil level
often during competitive driving.
Competitive Driving Mode can be
selected. See Driver Mode Control
0 184.
Axle Fluid
Axles must have 805 km (500 mi)
before being used in track driving.
The rear axle fluid temperatures may
be higher than when driving in severe
conditions. Drain and refill with new
fluid after the first racing or
competitive driving event, and then
after every 24 hours of racing or
competitive driving. See Recommended
Fluids and Lubricants 0313.
Caution
During a first time track or racing
event, high axle temperatures can
occur. Damage could be caused to
the axle and would not be covered
by the vehicle warranty. Do not
drive as long or as fast the first
time the vehicle is driven on the
track or raced.
. The axle lubricant should be
replaced with new lubricant.
. Additional cooling capacity is also
required for continuous
competitive driving.
Engine Oil
Check the oil level often during track
events and competitive driving and
keep the oil level at or near the
upper mark.
Fuel
Use premium unleaded gasoline with
a posted octane rating of 93 at a track
event. Unleaded gasoline with a
posted octane rating of 91 may be
used, but performance will be
degraded.
Automatic Transmission Fluid
Have the transmission fluid set to the
track specific oil level prior to track
usage. Transmission fluid should be
changed after every 15 hours of track
usage. Any transmission level set or
change should be performed at your
dealer.
Brakes
Brake cooling can be improved if the
front brake disc splash shield and
front tire deflector are removed.
Removing the shield will require that
the suspension bushings and wheel

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
DRIVING AND OPERATING 151
For continuous road/street course use,
hot tire inflation pressure may be
adjusted to a minimum of 270 kPa
(39 psi).
Return the tires to the recommended
cold tire inflation pressure when
high-speed driving has ended. See
Vehicle Load Limits0154 and
Tire Pressure 0275.
Driving on Wet Roads
Rain and wet roads can reduce vehicle
traction and affect your ability to stop
and accelerate. Always drive slower in
these types of driving conditions and
avoid driving through large puddles
and deep-standing or flowing water.
{Warning
Wet brakes can cause crashes. They
might not work as well in a quick
stop and could cause pulling to one
side. You could lose control of the
vehicle.
(Continued)
Warning (Continued)
After driving through a large puddle
of water or a car/vehicle wash,
lightly apply the brake pedal until
the brakes work normally.
Flowing or rushing water creates
strong forces. Driving through
flowing water could cause the
vehicle to be carried away. If this
happens, you and other vehicle
occupants could drown. Do not
ignore police warnings and be very
cautious about trying to drive
through flowing water.
Hydroplaning
Hydroplaning is dangerous. Water can
build up under the vehicle's tires so
they actually ride on the water. This
can happen if the road is wet enough
and you are going fast enough. When
the vehicle is hydroplaning, it has
little or no contact with the road.
There is no hard and fast rule about
hydroplaning. The best advice is to
slow down when the road is wet.
Other Rainy Weather Tips
Besides slowing down, other wet
weather driving tips include:
.Allow extra following distance.
. Pass with caution.
. Keep windshield wiping equipment
in good shape.
. Keep the windshield washer fluid
reservoir filled.
. Have good tires with proper tread
depth. See Tires0267.
. Turn off cruise control.
Hill and Mountain Roads
Driving on steep hills or through
mountains is different than driving on
flat or rolling terrain. Tips include:
.Keep the vehicle serviced and in
good shape.
. Check all fluid levels and brakes,
tires, cooling system, and
transmission.
. Shift to a lower gear when going
down steep or long hills.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
228 DRIVING AND OPERATING
after towing at high altitude on steep
uphill grades, the vehicle could show
signs similar to engine overheating. To
avoid this, let the engine run,
preferably on level ground, with the
transmission in P (Park) for a few
minutes before turning the engine off.
If the overheat warning comes on, see
Engine Overheating0250.
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 a 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 0303. 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
0 250.
Trailer Towing
Caution
Towing a trailer improperly can
damage the vehicle and result in
costly repairs not covered by the
vehicle warranty. To tow a trailer
correctly, follow the directions in
this section and see your dealer for
important information about
towing a trailer with the vehicle.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
VEHICLE CARE 233
Vehicle Care
General Information
General Information . . . . . . . . . . . . . 234
California Proposition65 Warning . . . . . . . . . . . . . . . . . . . . . 234
California Perchlorate Materials Requirements . . . . . . . . . . . . . . . . . . . 235
Accessories and Modifications . . . . . . . . . . . . . . . . . . . 235
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . . . . . . 235
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 236
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . . . . . . 238
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . 241
Engine Oil Life System . . . . . . . . . . . 243
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244
Engine Air Cleaner/Filter . . . . . . . . . 245
Cooling System . . . . . . . . . . . . . . . . . . . 246
Engine Overheating . . . . . . . . . . . . . . 250
Washer Fluid . . . . . . . . . . . . . . . . . . . . . 252
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252
Brake Fluid . . . . . . . . . . . . . . . . . . . . . . . 253
Battery - North America . . . . . . . . . 254
All-Wheel Drive . . . . . . . . . . . . . . . . . . 255 Starter Switch Check . . . . . . . . . . . . . 255
Park Brake and P (Park)
Mechanism Check . . . . . . . . . . . . . . 256
Wiper Blade Replacement . . . . . . . 256
Windshield Replacement . . . . . . . . 257
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . . . . 257
Headlamp Aiming
Front Headlamp Aiming . . . . . . . . . 258
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . . . . . 258
Halogen Bulbs . . . . . . . . . . . . . . . . . . . . 258
High Intensity Discharge (HID) Lighting . . . . . . . . . . . . . . . . . . . . . . . . . 259
LED Lighting . . . . . . . . . . . . . . . . . . . . . 259
Front Turn Signal Lamps . . . . . . . . 259
Electrical System
Electrical System Overload . . . . . . 259
Fuses and Circuit Breakers . . . . . . 260
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260
Instrument Panel Fuse Block . . . . 262
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 267
All-Season Tires . . . . . . . . . . . . . . . . . . 268
Winter Tires . . . . . . . . . . . . . . . . . . . . . . 268
Run-Flat Tires . . . . . . . . . . . . . . . . . . . . 269 Self-Sealing Tires . . . . . . . . . . . . . . . . . 269
Low-Profile Tires . . . . . . . . . . . . . . . . . 270
Summer Tires . . . . . . . . . . . . . . . . . . . . 270
Tire Sidewall Labeling . . . . . . . . . . . 270
Tire Designations . . . . . . . . . . . . . . . . . 272
Tire Terminology and
Definitions . . . . . . . . . . . . . . . . . . . . . . 272
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . 275
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . . . . . . 276
Tire Pressure Monitor System . . . 276
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . . . . . . 277
Tire Inspection . . . . . . . . . . . . . . . . . . . 280
Tire Rotation . . . . . . . . . . . . . . . . . . . . . 281
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 282
Buying New Tires . . . . . . . . . . . . . . . . 282
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . . . . . . 284
Uniform Tire Quality Grading . . . 284
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . . . . . . . 285
Wheel Replacement . . . . . . . . . . . . . . 286
Tire Chains . . . . . . . . . . . . . . . . . . . . . . . 286
If a Tire Goes Flat . . . . . . . . . . . . . . . . 287Jump Starting
Jump Starting - North America . . . . . . . . . . . . . . . . . . . . . . . . . 288

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
VEHICLE CARE 239
1. Windshield Washer FluidReservoir. See Washer Fluid
0 252.
2. Engine Coolant Surge Tank and Pressure Cap. See Cooling System
0 246.
3. Engine Air Cleaner/Filter 0245.
4. Engine Cooling Fan (Out of View). See Cooling System 0246. 5. Engine Oil Fill Cap. See
Engine Oil
0 241.
6. Engine Oil Dipstick. See Engine
Oil 0241.
7. Remote Positive (+) Battery Terminal. See Jump Starting -
North America 0288.
8. Brake Fluid Reservoir. See Brake
Fluid 0253. 9. Remote Negative (-) Battery
Terminal. See Jump Starting -
North America 0288.
10. Engine Compartment Fuse Block
0260.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-13183937) -
2020 - crc - 4/28/20
VEHICLE CARE 241
1. Windshield Washer FluidReservoir. See Washer Fluid
0 252.
2. Engine Coolant Surge Tank and Pressure Cap. See Cooling System
0 246.
3. Engine Air Cleaner/Filter 0245.
4. Engine Cooling Fan (Out of View). See Cooling System 0246.
5. Engine Oil Fill Cap. See Engine Oil
0 241.
6. Cooling System Air Bleeder Cap. See Cooling System 0246.
7. Engine Oil Dipstick. See Engine
Oil 0241.
8. Remote Positive (+) Battery Terminal. See Jump Starting -
North America 0288.
9. Brake Fluid Reservoir. See Brake
Fluid 0253.
10. Remote Negative (-) Battery Terminal. See Jump Starting -
North America 0288.
11. Engine Compartment Fuse Block. SeeEngine Compartment Fuse
Block 0260.Engine Oil
To ensure proper engine performance
and long life, careful attention must
be paid to engine oil. Following these
simple, but important steps will help
protect your investment:
.
Use engine oil approved to the
proper specification and of the
proper viscosity grade. See
“Selecting the Right Engine Oil” in
this section.
. Check the engine oil level regularly
and maintain the proper oil level.
See “Checking Engine Oil” and
“When to Add Engine Oil” in this
section.
. Change the engine oil at the
appropriate time. See Engine Oil
Life System 0243.
. Always dispose of engine oil
properly. See “What to Do with
Used Oil” in this section.
Checking Engine Oil
Check the engine oil level regularly,
every 650 km (400 mi), especially prior
to a long trip. The engine oil dipstick handle is a loop. See
Engine
Compartment Overview 0238 for the
location.
{Warning
The engine oil dipstick handle may
be hot; it could burn you. Use a
towel or glove to touch the dipstick
handle.
If a low oil Driver Information Center
(DIC) message displays, check the oil
level.
Follow these guidelines:
. To get an accurate reading, park
the vehicle on level ground. Check
the engine oil level after the
engine has been off for at least
two hours. Checking the engine oil
level on steep grades or too soon
after engine shutoff can result in
incorrect readings. Accuracy
improves when checking a cold
engine prior to starting. Remove
the dipstick and check the level.