engine overheat CADILLAC CT6 2016 User Guide

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
Vehicle Care 277
Engine Coolant The cooling system in the vehicle is
filled with DEX-COOL ®
engine
coolant. This coolant needs to be
checked and replaced at
appropriate intervals. See
Maintenance Schedule 0 344 .
The following explains the cooling
system and how to check and add
coolant when it is low. If there is a
problem with engine overheating,
see Engine Overheating 0 280 .
What to Use
{ WarningAdding only plain water or some
other liquid to the cooling system
can be dangerous. Plain water
and other liquids, can boil before
the proper coolant mixture will.
The coolant warning system is set
for the proper coolant mixture.
With plain water or the wrong
mixture, the engine could get too
hot but you would not get the
(Continued) Warning (Continued) overheat warning. The engine
could catch fire and you or others
could be burned. Use a 50/
50 mixture of clean, drinkable
water and DEX-COOL coolant.
Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
coolant. If using this mixture,
nothing else needs to be added.
This mixture:
.
Gives freezing protection down
to − 37 °C ( − 34 °F), outside
temperature.
.
Gives boiling protection up to
129 °C (265 °F), engine
temperature.
.
Protects against rust and
corrosion.
.
Will not damage aluminum parts.
.
Helps keep the proper engine
temperature. CautionIf improper coolant mixture,
inhibitors, or additives are used in
the vehicle cooling system, the
engine could overheat and be
damaged. Too much water in the
mixture can freeze and crack
engine cooling parts. The repairs
would not be covered by the
vehicle warranty. Use only the
proper mixture of engine coolant
for the cooling system. See
Recommended Fluids and
Lubricants 0 353 .
Never dispose of engine coolant by
putting it in the trash, pouring it on
the ground, or into sewers, streams,
or bodies of water. Have the coolant
changed by an authorized service
center, familiar with legal
requirements regarding used
coolant disposal. This will help
protect the environment and your
health.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
278 Vehicle Care Checking Coolant The vehicle must be on a level
surface when checking the coolant
level.
2.0L L4 and 3.0L V6 Engine
Coolant Surge Tank 3.6L V6 Engine Coolant
Surge Tank
Check to see if coolant is visible in
the coolant surge tank. If the coolant
inside the coolant surge tank is
boiling, do not do anything else until
it cools down. See Engine
Overheating 0 280 .
The coolant surge tank is in the
engine compartment on the
passenger side of the vehicle. See
Engine Compartment
Overview 0 265 . How to Add Coolant to the
Coolant Surge Tank
CautionThis vehicle has a specific
coolant fill procedure. Failure to
follow this procedure could cause
the engine to overheat and be
severely damaged.
If no problem is found, check to see
if coolant is visible in the coolant
surge tank. If coolant is visible but
the coolant level mark is not visible,
add a 50/50 mixture of clean,
drinkable water and DEX-COOL
coolant at the coolant surge tank to
the top rib on the middle of the tank,
but be sure the cooling system,
including the coolant surge tank
pressure cap, is cool before this is
done. See Engine
Overheating 0 280 .

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
Vehicle Care 279
{ WarningSteam and scalding liquids from a
hot cooling system can blow out
and burn you badly. Never turn
the cap when the cooling system,
including the surge tank pressure
cap, is hot. Wait for the cooling
system and surge tank pressure
cap to cool.
{ WarningAdding only plain water or some
other liquid to the cooling system
can be dangerous. Plain water
and other liquids, can boil before
the proper coolant mixture will.
The coolant warning system is set
for the proper coolant mixture.
With plain water or the wrong
mixture, the engine could get too
hot but you would not get the
overheat warning. The engine
could catch fire and you or others
(Continued) Warning (Continued) could be burned. Use a 50/
50 mixture of clean, drinkable
water and DEX-COOL coolant.
CautionIn cold weather, water can freeze
and crack the engine, radiator,
heater core, and other parts. Use
the recommended coolant and
the proper coolant mixture.
{ Warning
You can be burned if you spill
coolant on hot engine parts.
Coolant contains ethylene glycol
and it will burn if the engine parts
are hot enough. Do not spill
coolant on a hot engine.
1. Remove the coolant surge tank
pressure cap when the cooling
system, including the coolant surge tank pressure cap and
upper radiator hose, is no
longer hot.
Turn the pressure cap slowly
counterclockwise about
one-quarter of a turn. If you
hear a hiss, wait for that to
stop. This will allow any
pressure still left to be vented
out the discharge hose.
2. Keep turning the pressure cap
slowly and remove it.
3. Fill the coolant surge tank with
the proper mixture to the
indicated level mark.
4. With the coolant surge tank
pressure cap off, start the
engine and let it run until you
can feel the upper radiator
hose getting hot. Watch out for
the engine cooling fan.
By this time, the coolant level
inside the coolant surge tank
may be lower. If the level is
lower, add more of the proper
mixture to the coolant surge
tank until the level reaches the
indicated level mark.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
280 Vehicle Care 5. Replace the pressure cap
tightly.
6. Verify coolant level after the
engine is shut off and the
coolant is cold. If necessary,
repeat coolant fill procedure
Steps 1 – 6.
If the coolant still is not at the
proper level when the system
cools down again, see your
dealer.
CautionIf the pressure cap is not tightly
installed, coolant loss and
possible engine damage may
occur. Be sure the cap is properly
and tightly secured.
Engine Overheating The vehicle has several indicators
to warn of the engine overheating.
There is an engine coolant
temperature gauge and an engine
coolant temperature warning light on the instrument cluster. See Engine
Coolant Temperature Gauge 0 128
and Engine Coolant Temperature
Warning Light 0 137 . The vehicle
may also display a message on the
Driver Information Center (DIC).
See Engine Cooling System
Messages 0 149 .
If the decision is made not to lift the
hood when this warning appears,
get service help right away. See
Roadside Service 0 364 .
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.
Caution
Running the engine without
coolant may cause damage or a
fire. Vehicle damage would not be
covered by the vehicle warranty. If Steam Is Coming from the
Engine Compartment
{ WarningSteam from an overheated engine
can burn you badly, even if you
just open the hood. Stay away
from the engine if you see or hear
steam coming from it. Just turn it
off and get everyone away from
the vehicle until it cools down.
Wait until there is no sign of
steam or coolant before you open
the hood.
If you keep driving when the
engine is overheated, the liquids
in it can catch fire. You or others
could be badly burned. Stop the
engine if it overheats, and get out
of the vehicle until the engine
is cool.
If No Steam Is Coming from
the Engine Compartment
If an engine overheat warning is
displayed but no steam can be seen
or heard, the problem may not be

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
Vehicle Care 281too serious. Sometimes the engine
can get a little too hot when the
vehicle:
.
Climbs a long hill on a hot day.
.
Stops after high-speed driving.
.
Idles for long periods in traffic.
If the overheat warning is displayed
with no sign of steam:
1. Turn the air conditioning off.
2. Turn the heater on to the
highest temperature and to the
highest fan speed. Open the
windows as necessary.
3. When it is safe to do so, pull off
the road, shift to P (Park) or
N (Neutral), and let the
engine idle.
If the engine coolant temperature
gauge is no longer in the
overheated area or the engine
coolant temperature warning light no
longer displays, the vehicle can be
driven. Continue to drive the vehicle
slowly for about 10 minutes. Keep a
safe distance from the vehicle in
front. If the warning does not come back on, continue to drive normally
and have the cooling system
checked for proper fill and function.
If the warning continues, pull over,
stop, and park the vehicle
right away.
If there is no sign of steam, idle the
engine for three minutes while
parked. If the warning is still
displayed, turn off the engine until it
cools down.
Washer Fluid What to Use When windshield washer fluid is
needed, be sure to read the
manufacturer's instructions before
use. If operating the vehicle in an
area where the temperature may fall
below freezing, use a fluid that has
sufficient protection against
freezing. Adding Washer Fluid
Open the cap with the washer
symbol on it. Add washer fluid until
the tank is full. See Engine
Compartment Overview 0 265 for
reservoir location.
Caution .
Do not use washer fluid that
contains any type of water
repellent coating. This can
cause the wiper blades to
chatter or skip.
.
Do not use engine coolant
(antifreeze) in the
windshield washer. It can
damage the windshield
washer system and paint.
(Continued)

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
388 Index E Electric Parking Brake . . . . . . . . . . 214
Electric Parking Brake Light . . . . 134
Electrical Equipment,
Add-On . . . . . . . . . . . . . . . . . . . . . . . 260
Electrical System
Engine Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . 290
Fuses and Circuit Breakers . . . 290
Instrument Panel Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . 293
Overload . . . . . . . . . . . . . . . . . . . . . 289
Rear Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . 295
Emergency
OnStar ®
. . . . . . . . . . . . . . . . . . . . . . 376
Engine
Air Cleaner/Filter . . . . . . . . . . . . . 273
Check and Service Engine
Soon Light . . . . . . . . . . . . . . . . . . 132
Compartment Overview . . . . . . . 265
Coolant . . . . . . . . . . . . . . . . . . . . . . . 277
Coolant Heater . . . . . . . . . . . . . . . 206
Coolant Temperature
Gauge . . . . . . . . . . . . . . . . . . . . . . 128 Engine (cont'd)
Coolant Temperature
Warning Light . . . . . . . . . . . . . . . 137
Cooling System . . . . . . . . . . . . . . . 275
Cooling System Messages . . . 149
Drive Belt Routing . . . . . . . . . . . . 360
Exhaust . . . . . . . . . . . . . . . . . . . . . . 209
Oil Life System . . . . . . . . . . . . . . . 272
Oil Messages . . . . . . . . . . . . . . . . . 149
Oil Pressure Gauge . . . . . . . . . . 126
Oil Pressure Light . . . . . . . . . . . . 138
Overheating . . . . . . . . . . . . . . . . . . 280
Power Messages . . . . . . . . . . . . . 150
Running While Parked . . . . . . . . 210
Starting . . . . . . . . . . . . . . . . . . . . . . . 204
Engine Oil
Temperature Gauge . . . . . . . . . . 127
Entry Lighting . . . . . . . . . . . . . . . . . . . 175
Equipment, Towing . . . . . . . . . . . . . 259
Event Data Recorders . . . . . . . . . . 373
Exit Lighting . . . . . . . . . . . . . . . . . . . . 176
Extender, Safety Belt . . . . . . . . . . . . 75
Exterior Lamp Controls . . . . . . . . . 170
Exterior Lamps Off Reminder . . . 172
Exterior Lighting Battery
Saver . . . . . . . . . . . . . . . . . . . . . . . . . 176 F Features
Memory . . . . . . . . . . . . . . . . . . . . . . . . . 12
Filter,
Engine Air Cleaner . . . . . . . . . . . 273
Flash-to-Pass . . . . . . . . . . . . . . . . . . . 172
Flashers, Hazard Warning . . . . . . 173
Flat Tire . . . . . . . . . . . . . . . . . . . . . . . . 320
Changing . . . . . . . . . . . . . . . . . . . . . 321
Floor Mats . . . . . . . . . . . . . . . . . . . . . . 341
Fluid
Automatic Transmission . . . . . . 273
Brakes . . . . . . . . . . . . . . . . . . . . . . . . 283
Washer . . . . . . . . . . . . . . . . . . . . . . . 281
Forward Collision Alert
(FCA) System . . . . . . . . . . . . . . . . . 237
Frequency Statement
Radio . . . . . . . . . . . . . . . . . . . . . . . . . 371
Front Automatic Braking
(FAB) System . . . . . . . . . . . . . . . . . 240
Front Pedestrian Braking
(FPB) System . . . . . . . . . . . . . . . . . 241
Front Seats
Heated and Ventilated . . . . . . . . . . 64
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . 251
Additives . . . . . . . . . . . . . . . . . . . . . 253
Economy Driving . . . . . . . . . . . . . . . 27

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
392 Index Online Owner Center . . . . . . . . . . . 364
OnStar . . . . . . . . . . . . . . . . . . . . . . . . . 373
OnStar ®
Additional
Information . . . . . . . . . . . . . . . . . . . . 379
OnStar ®
Connections . . . . . . . . . . . 377
OnStar ®
Diagnostics . . . . . . . . . . . . 379
OnStar ®
Emergency . . . . . . . . . . . . 376
OnStar ®
Navigation . . . . . . . . . . . . . 376
OnStar ®
Overview . . . . . . . . . . . . . . 375
OnStar ®
Security . . . . . . . . . . . . . . . 376
Ordering
Service Publications . . . . . . . . . . 370
Outlets
Power . . . . . . . . . . . . . . . . . . . . . . . . .114
Overheating, Engine . . . . . . . . . . . . 280
P Park
Shifting Into . . . . . . . . . . . . . . . . . . . 207
Shifting Out of . . . . . . . . . . . . . . . . 208
Parking
Brake and P (Park)
Mechanism Check . . . . . . . . . . 286
Over Things That Burn . . . . . . . 209
Parking or Backing
Assistance Systems . . . . . . . . . . 231
Passenger Airbag Status
Indicator . . . . . . . . . . . . . . . . . . . . . . 130 Passenger Compartment Air
Filter . . . . . . . . . . . . . . . . . . . . . . . . . . 190
Passenger Sensing System . . . . . 82
Pedestrian Ahead Indicator . . . . . 136
Perchlorate Materials
Requirements, California . . . . . . 262
Personalization
Vehicle . . . . . . . . . . . . . . . . . . . . . . . 157
Power
Door Locks . . . . . . . . . . . . . . . . . . . . . 39
Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Outlets . . . . . . . . . . . . . . . . . . . . . . . .114
Protection, Battery . . . . . . . . . . . . 176
Retained Accessory (RAP) . . . 206
Seat Adjustment . . . . . . . . . . . . . . . . 60
Windows . . . . . . . . . . . . . . . . . . . . . . . 52
Pregnancy, Using Safety Belts . . . 74
Premium Care Maintenance
Cadillac . . . . . . . . . . . . . . . . . . . . . . . 344
Privacy
Vehicle Data Recording . . . . . . . 372
Program
Courtesy Transportation . . . . . . 367
Proposition
65 Warning,
California . . . . . . . . . . . .262, 284, 327 R Radio Frequency Statement . . . . 371
Reading Lamps . . . . . . . . . . . . . . . . . 175
Rear Camera Mirror . . . . . . . . . . . . . 50
Rear Seat Armrest . . . . . . . . . . . . . . . 68
Rear Seat Pass-Through Door . . . 69
Rear Seats . . . . . . . . . . . . . . . . . . . . . . 66
Heated and Ventilated . . . . . . . . . . 69
Rear Storage . . . . . . . . . . . . . . . . . . . 107
Rear Window Sunshade . . . . . . . . . 54
Rearview Mirrors
Automatic Dimming . . . . . . . . . . . . . 49
Reclining Seatbacks . . . . . . . . . . . . . 62
Recommended Fluids and
Lubricants . . . . . . . . . . . . . . . . . . . . . 353
Recorder
Video . . . . . . . . . . . . . . . . . . . . . . . . . 250
Records
Maintenance . . . . . . . . . . . . . . . . . . 356
Recreational Vehicle Towing . . . . 331
Remote Keyless Entry (RKE)
System . . . . . . . . . . . . . . . . . . . . . . . . . 29
Remote Vehicle Start . . . . . . . . . . . . 36
Replacement Bulbs . . . . . . . . . . . . . 289
Replacement Parts
Airbags . . . . . . . . . . . . . . . . . . . . . . . . . 87
Maintenance . . . . . . . . . . . . . . . . . . 354
Replacing Airbag System . . . . . . . . 87