2016 CADILLAC CT6 check engine

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
Driving and Operating 215The vehicle has an Electric Parking
Brake (EPB). The EPB can always
be activated, even if the ignition is
off. To prevent draining the battery,
avoid repeated cycles of the EPB
system when the engine is not
running.
The system has a red parking brake
status light and an amber parking
brake warning light. See Electric
Parking Brake Light 0 134
and Service Electric Parking Brake
Light 0 134 . There are also parking
brake-related Driver Information
Center (DIC) messages. See Brake
System Messages 0 147 . In case of
insufficient electrical power, the EPB
cannot be applied or released.
Before leaving the vehicle, check
the red parking brake status light to
ensure that the parking brake is
applied.
EPB Apply
To apply the EPB:
1. Be sure the vehicle is at a
complete stop.
2. Press the EPB switch
momentarily. The red parking brake status light
will flash and then stay on once the
EPB is fully applied. If the red
parking brake status light flashes
continuously, then the EPB is only
partially applied or there is a
problem with the EPB. A DIC
message will display. Release the
EPB and try to apply it again. If the
light does not come on, or keeps
flashing, have the vehicle serviced.
Do not drive the vehicle if the red
parking brake status light is flashing.
See your dealer. See Electric
Parking Brake Light 0 134 .
If the amber parking brake warning
light is on, press the EPB switch
and hold it. Continue to hold the
switch until the red parking brake
status light remains on. If the amber
parking brake warning light remains
on, see your dealer.
If the EPB is applied while the
vehicle is moving, the vehicle will
decelerate as long as the switch is
pressed. If the switch is pressed
until the vehicle comes to a stop,
the EPB will remain applied. The vehicle may automatically apply
the EPB in some situations when
the vehicle is not moving. This is
normal, and is done to periodically
check the correct operation of the
EPB system.
If the EPB fails to apply, block the
rear wheels to prevent vehicle
movement.
EPB Release To release the EPB:
1. Place the ignition in the ACC/
ACCESSORY or ON/
RUN mode.
2. Apply and hold the brake
pedal.
3. Push down momentarily on the
EPB switch.
The EPB is released when the red
parking brake status light is off.
If the amber parking brake warning
light is on, release the EPB by
pushing down on the EPB switch
and holding it down. Continue to
hold the switch until the red parking

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
218 Driving and Operating vehicle wheel brakes to assist the
driver in keeping the vehicle on the
intended path.
If cruise control is being used and
traction control or StabiliTrak begins
to limit wheel spin, cruise control will
disengage. Cruise control may be
turned back on when road
conditions allow.
Both systems come on
automatically when the vehicle is
started and begins to move. The
systems may be heard or felt while
they are operating or while
performing diagnostic checks. This
is normal and does not mean there
is a problem with the vehicle.
It is recommended to leave both
systems on for normal driving
conditions, but it may be necessary
to turn TCS off if the vehicle gets
stuck in sand, mud, ice, or snow.
See If the Vehicle Is Stuck 0 198
and “ Turning the Systems Off and
On ” later in this section. The indicator light for both systems
is in the instrument cluster. This
light will:
.
Flash when TCS is limiting
wheel spin.
.
Flash when StabiliTrak is
activated.
.
Turn on and stay on when either
system is not working.
If either system fails to turn on or to
activate, a message displays in the
Driver Information Center (DIC),
and
d comes on and stays on to
indicate that the system is inactive
and is not assisting the driver in
maintaining control. The vehicle is
safe to drive, but driving should be
adjusted accordingly.
If
d comes on and stays on:
1. Stop the vehicle. 2. Turn the engine off and wait
15 seconds.
3. Start the engine.
4. Drive the vehicle.
If
d comes on and stays on, the
vehicle may need more time to
diagnose the problem. If the
condition persists, see your dealer.
Turning the Systems Off
and On

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
Driving and Operating 253
California Fuel
Requirements If the vehicle is certified to meet
California Emissions Standards, it is
designed to operate on fuels that
meet California specifications. See
the underhood emission control
label. If this fuel is not available in
states adopting California Emissions
Standards, the vehicle will operate
satisfactorily on fuels meeting
federal specifications, but emission
control system performance might
be affected. The malfunction
indicator lamp could turn on and the
vehicle may not pass a smog-check
test. See Malfunction Indicator
Lamp (Check Engine Light) 0 132 .
If this occurs, return to your
authorized dealer for diagnosis. If it
is determined that the condition is
caused by the type of fuel used,
repairs may not be covered by the
vehicle warranty. Fuels in Foreign
Countries If planning to drive in countries
outside the U.S. or Canada, the
proper fuel might be hard to find.
Check regional auto club or fuel
retail brand websites for availability
in the country where driving. Never
use leaded gasoline, fuel containing
methanol, manganese, or any other
fuel not recommended. Costly
repairs caused by use of improper
fuel would not be covered by the
vehicle warranty.
Fuel Additives To keep fuel systems clean, TOP
TIER Detergent Gasoline is
recommended. See Fuel 0 251 .
If TOP TIER Detergent Gasoline is
not available, one bottle of Fuel
System Treatment PLUS added to
the fuel tank at every engine oil
change, can help. Fuel System
Treatment PLUS is the only
gasoline additive recommended by
General Motors. It is available at
your dealer. Filling the Tank
{ WarningFuel vapors and fuel fires burn
violently and can cause injury or
death.
.
To help avoid injuries to you
and others, read and follow
all the instructions on the
fuel pump island.
.
Turn off the engine when
refueling.
.
Keep sparks, flames, and
smoking materials away
from fuel.
.
Do not leave the fuel pump
unattended.
.
Do not use a cell phone
while refueling.
.
Do not reenter the vehicle
while pumping fuel.
.
Keep children away from
the fuel pump and never let
children pump fuel.
(Continued)

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
256 Driving and Operating .
Do not tow a trailer during the
first 2 414 km (1,500 mi) to
prevent damage to the engine,
axle, or other parts.
.
Then during the first 800 km
(500 mi) of trailer towing, do not
drive over 80 km/h (50 mph) and
do not make starts at full throttle.
.
Vehicles can tow in D (Drive).
Shift the transmission to a lower
gear if the transmission shifts
too often under heavy loads and/
or hilly conditions.
.
Do not use Adaptive Cruise
Control when towing.
.
The Front Automatic Braking
System should be set to Off
when towing. See Front
Automatic Braking (FAB)
System 0 240 .
.
Turn off Parking Assist when
towing. { WarningWhen towing a trailer, exhaust
gases may collect at the rear of
the vehicle and enter if the
liftgate, trunk/hatch, or rear-most
window is open.
When towing a trailer:
.
Do not drive with the
liftgate, trunk/hatch,
or rear-most window open.
.
Fully open the air outlets on
or under the instrument
panel.
.
Also adjust the climate
control system to a setting
that brings in only outside
air. See “ Climate Control
Systems ” in the Index.
For more information about
carbon monoxide, see Engine
Exhaust 0 209 .
Towing a trailer requires a certain
amount of experience. The
combination you are driving is
longer and not as responsive as the vehicle itself. Get acquainted with
the handling and braking of the rig
before setting out for the open road.
Before starting, check all trailer hitch
parts and attachments, safety
chains, electrical connectors, lamps,
tires, and mirrors. If the trailer has
electric brakes, start the
combination moving and then apply
the trailer brake controller by hand
to be sure the brakes work.
During the trip, check occasionally
to be sure that the load is secure
and the lamps and any trailer
brakes still work.
Following Distance Stay at least twice as far behind the
vehicle ahead as you would when
driving the vehicle without a trailer.
This can help to avoid heavy
braking and sudden turns.
Passing
More passing distance is needed
when towing a trailer. The
combination will not accelerate as
quickly and is longer so it is

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
Driving and Operating 257necessary to go much farther
beyond the passed vehicle before
returning to the lane.
Backing Up Hold the bottom of the steering
wheel with one hand. To move the
trailer to the left, move that hand to
the left. To move the trailer to the
right, move your hand to the right.
Always back up slowly and,
if possible, have someone
guide you.
Making Turns
CautionMaking very sharp turns while
trailering could cause the trailer to
come in contact with the vehicle.
The vehicle could be damaged.
Avoid making very sharp turns
while trailering.
When turning with a trailer, make
wider turns than normal. Do this so
the trailer will not strike soft
shoulders, curbs, road signs, trees, or other objects. Avoid jerky or
sudden maneuvers. Signal well in
advance.
If the trailer turn signal bulbs burn
out, the arrows on the instrument
cluster will still flash for turns. It is
important to check occasionally to
be sure the trailer bulbs are still
working.
Driving on Grades Reduce speed and shift to a lower
gear before starting down a long or
steep downgrade. If the
transmission is not shifted down, the
brakes might get hot and no longer
work well.
Vehicles can tow in D (Drive). Shift
the transmission to a lower gear if
the transmission shifts too often
under heavy loads and/or hilly
conditions.
When towing at high altitude on
steep uphill grades, consider the
following: Engine coolant will boil at
a lower temperature than at normal
altitudes. If the engine is turned off
immediately after towing at high
altitude on steep uphill grades, the vehicle may show signs similar to
engine overheating. To avoid this,
let the engine run while parked,
preferably on level ground, with the
automatic transmission in P (Park)
for a few minutes before turning the
engine off. If the overheat warning
comes on, see Engine
Overheating 0 280 .
Parking on Hills
{ WarningParking the vehicle on a hill with
the trailer attached can be
dangerous. If something goes
wrong, the rig could start to move.
People can be injured, and both
the vehicle and the trailer can be
damaged. When possible, always
park the rig on a flat surface.
If parking the rig 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.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
258 Driving and Operating 2. Have someone place chocks
under the trailer wheels.
3. When the wheel chocks are in
place, release the regular
brakes until the chocks absorb
the load.
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.
2. Start the engine.
3. Shift into a gear.
4. Release the parking brake.
5. Let up on the brake pedal.
6. Drive slowly until the trailer is
clear of the chocks.
7. Stop and have someone pick
up and store the chocks. Maintenance when Trailer
Towing The vehicle needs service more
often when pulling a trailer. See
Maintenance Schedule 0 344 .
Things that are especially important
in trailer operation are automatic
transmission fluid, engine oil, axle
lubricant, belts, cooling system, and
brake system. It is a good idea to
inspect these before and during
the trip.
Check periodically to see that all
hitch nuts and bolts are tight.
Trailer Towing Before pulling a trailer, three
important considerations have to do
with weight:
.
Weight of the trailer.
.
Weight of the trailer tongue.
.
Total weight on your vehicle's
tires.
Weight of the Trailer
How heavy can a trailer safely be? It should never weigh more than
454 kg (1,000 lb). But even that can
be too heavy.
It depends on how the rig is used.
For example, speed, altitude, road
grades, outside temperature, and
how much the vehicle is used to pull
a trailer are all important. It can
depend on any special equipment
on the vehicle, and the amount of
tongue weight the vehicle can carry.
See “ Weight of the Trailer Tongue ”
following.
Maximum trailer weight is calculated
assuming only the driver is in the
tow vehicle and it has all the
required trailering equipment. The
weight of additional optional
equipment, passengers, and cargo
in the tow vehicle must be
subtracted from the maximum trailer
weight.
Ask your dealer for trailering
information or advice, or write us at
our Customer Assistance Offices.
See Customer Assistance
Offices 0 363 .

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
260 Driving and Operating Safety Chains Always attach chains between the
vehicle and the trailer. Cross the
safety chains under the tongue of
the trailer to help prevent the tongue
from contacting the road if it
becomes separated from the hitch.
Leave enough slack so the rig can
turn. Never allow safety chains to
drag on the ground.
Trailer Brakes Does the trailer have its own
brakes? Be sure to read and follow
the instructions for the trailer brakes
so they are installed, adjusted, and
maintained properly.
Because the vehicle has antilock
brakes, do not tap into the vehicle's
brake system. If this is done, both
brake systems will not work well or
at all. Conversions and
Add-Ons Add-On Electrical
Equipment
{ WarningThe Data Link Connector (DLC) is
used for vehicle service and
Emission Inspection/Maintenance
testing. See Malfunction Indicator
Lamp (Check Engine Light)
0 132 . A device connected to the
DLC — such as an aftermarket
fleet or driver-behavior tracking
device — may interfere with
vehicle systems. This could affect
vehicle operation and cause a
crash. Such devices may also
access information stored in the
vehicle ’ s systems. CautionSome electrical equipment can
damage the vehicle or cause
components to not work and
would not be covered by the
vehicle warranty. Always check
with your dealer before adding
electrical equipment.
Add-on equipment can drain the
vehicle's 12-volt battery, even if the
vehicle is not operating.
The vehicle has an airbag system.
Before attempting to add anything
electrical to the vehicle, see
Servicing the Airbag-Equipped
Vehicle 0 86
and Adding Equipment to the
Airbag-Equipped Vehicle 0 86 .

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-9235592) -
2016 - crc - 11/6/15
Vehicle Care 261
Vehicle Care General Information General Information . . . . . . . . . . 262
California Proposition
65 Warning . . . . . . . . . . . . . . . . . 262
California Perchlorate
Materials Requirements . . . . . 262
Accessories and
Modifications . . . . . . . . . . . . . . . . 262
Vehicle Checks Doing Your Own
Service Work . . . . . . . . . . . . . . . 263
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 264
Engine Compartment
Overview . . . . . . . . . . . . . . . . . . . . 265
Engine Oil . . . . . . . . . . . . . . . . . . . . 270
Engine Oil Life System . . . . . . . 272
Automatic Transmission
Fluid . . . . . . . . . . . . . . . . . . . . . . . . 273
Engine Air Cleaner/Filter . . . . . . 273
Cooling System . . . . . . . . . . . . . . 275
Engine Coolant . . . . . . . . . . . . . . . 277
Engine Overheating . . . . . . . . . . 280
Washer Fluid . . . . . . . . . . . . . . . . . 281
Brakes . . . . . . . . . . . . . . . . . . . . . . . 282
Brake Fluid . . . . . . . . . . . . . . . . . . . 283
Battery - North America . . . . . . 284
All-Wheel Drive . . . . . . . . . . . . . . . 284 Starter Switch Check . . . . . . . . . 285
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 285
Park Brake and P (Park)
Mechanism Check . . . . . . . . . . 286
Wiper Blade Replacement . . . . 286
Windshield Replacement . . . . . 287
Headlamp Aiming Headlamp Aiming . . . . . . . . . . . . 287
Bulb Replacement Bulb Replacement . . . . . . . . . . . . 288
LED Lighting . . . . . . . . . . . . . . . . . 288
License Plate Lamp . . . . . . . . . . 288
Replacement Bulbs . . . . . . . . . . . 289
Electrical System Electrical System Overload . . . 289
Fuses and Circuit Breakers . . . 290
Engine Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . 290
Instrument Panel Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . 293
Rear Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . 295
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 299
All-Season Tires . . . . . . . . . . . . . . 300
Winter Tires . . . . . . . . . . . . . . . . . . 300 Low-Profile Tires . . . . . . . . . . . . . 300
Summer Tires . . . . . . . . . . . . . . . . 301
Tire Sidewall Labeling . . . . . . . . 301
Tire Designations . . . . . . . . . . . . . 303
Tire Terminology and
Definitions . . . . . . . . . . . . . . . . . . 304
Tire Pressure . . . . . . . . . . . . . . . . . 306
Tire Pressure for High-Speed
Operation . . . . . . . . . . . . . . . . . . . 308
Tire Pressure Monitor
System . . . . . . . . . . . . . . . . . . . . . . 308
Tire Pressure Monitor
Operation . . . . . . . . . . . . . . . . . . . 309
Tire Inspection . . . . . . . . . . . . . . . . 312
Tire Rotation . . . . . . . . . . . . . . . . . 313
When It Is Time for New
Tires . . . . . . . . . . . . . . . . . . . . . . . . 314
Buying New Tires . . . . . . . . . . . . . 315
Different Size Tires and
Wheels . . . . . . . . . . . . . . . . . . . . . . 316
Uniform Tire Quality
Grading . . . . . . . . . . . . . . . . . . . . . 316
Wheel Alignment and Tire
Balance . . . . . . . . . . . . . . . . . . . . . 318
Wheel Replacement . . . . . . . . . . 318
Tire Chains . . . . . . . . . . . . . . . . . . . 319
If a Tire Goes Flat . . . . . . . . . . . . 320
Tire Changing . . . . . . . . . . . . . . . . 321
Compact Spare Tire . . . . . . . . . . 326