
GMC Canyon/Canyon Denali Owner Manual (GMNA-Localizing-U.S./Canada-
14430430) - 2021 - CRC - 9/9/20
230 Driving and Operating
If the CHECK TRAILER WIRING message only
reappears when connecting the trailer wiring
harness to the vehicle, the electrical fault is
on the trailer side.
SERVICE TRAILER BRAKE SYSTEM: This
message will display when there is a
problem with the ITBC system. If this
message continues over multiple ignition
cycles, have the vehicle serviced.
If either the CHECK TRAILER WIRING or
SERVICE TRAILER BRAKE SYSTEM message
displays while driving, the ITBC system may
not be fully functional or may not function
at all. When traffic conditions allow,
carefully pull the vehicle over to the side of
the road and turn the ignition off. Check the
wiring connection to the trailer and turn the
ignition back on. If either of these messages
continues, either the vehicle or trailer needs
service.
A GM dealer may be able to diagnose and
repair problems with the trailer. However,
any diagnosis and repair of the trailer is not
covered under the vehicle warranty. Contact
your trailer dealer for assistance with trailer
repairs and trailer warranty information.Trailer Sway Control (TSC)
Vehicles with StabiliTrak/Electronic Stability
Control (ESC) have a Trailer Sway Control
(TSC) feature. Trailer sway is unintended
side-to-side motion of a trailer while towing.
If the vehicle is towing a trailer and the TSC
detects that sway is increasing, the vehicle
brakes are selectively applied at each wheel,
to help reduce excessive trailer sway.
If equipped with the Integrated Trailer Brake
Control (ITBC) system, and the trailer has an
electric brake system, StabiliTrak/ESC may
also apply the trailer brakes.
If TSC is enabled, the Traction Control
System (TCS)/StabiliTrak/ESC warning light
will flash on the instrument cluster. Reducevehicle speed by gradually removing your
foot from the accelerator. If trailer sway
continues, StabiliTrak/ESC can reduce engine
torque to help slow the vehicle. TSC will not
function if StabiliTrak/ESC is turned off. See
Traction Control/Electronic Stability Control
0
204.
{Warning
Trailer sway can result in a crash and in
serious injury or death, even if the
vehicle is equipped with TSC.
If the trailer begins to sway, reduce
vehicle speed by gradually removing your
foot from the accelerator. Then pull over
to check the trailer and vehicle to help
correct possible causes, including an
improperly or overloaded trailer,
unrestrained cargo, improper trailer hitch
configuration, or improperly inflated or
incorrect vehicle or trailer tires. See
Towing Equipment 0224 for trailer
ratings and hitch setup recommendations.

GMC Canyon/Canyon Denali Owner Manual (GMNA-Localizing-U.S./Canada-
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Driving and Operating 231
Aftermarket Electronic Trailer Sway
Control Devices
Some trailers may come equipped with an
electronic device designed to reduce or
control trailer sway. Aftermarket equipment
manufacturers also offer similar devices that
connect to the wiring between the trailer
and the vehicle. These devices may interfere
with the vehicle’s trailer brake or other
systems, including integrated anti-sway
systems, if equipped. Messages related to
trailer connections or trailer brakes could
appear on the DIC. The effects of these
aftermarket devices may have on vehicle
handling or trailer brake performance is not
known.
{Warning
Use of aftermarket electronic trailer sway
control devices could result in reduced
trailer brake performance, loss of trailer
brakes, or other malfunctions, and result
in a crash. You or others could be
seriously injured or killed. Before using
one of these devices:(Continued)
Warning (Continued)
.Ask the device or trailer manufacturer
if the device has been thoroughly
tested for compatibility with the
make, model, and year of your vehicle
and any optional equipment installed
on your vehicle.
.Before driving, check the trailer brakes
are working properly, if equipped.
Drive the vehicle with the trailer
attached on a level road surface that
is free of traffic at about 32-40 km/h
(20-25 mph) and fully apply the
manual trailer brake apply lever. Also,
check the trailer brake lamps and
other lamps are functioning correctly.
.If the trailer brakes are not operating
properly at any time, or if a DIC
message indicates problems with the
trailer connections or trailer brakes,
carefully pull the vehicle over to the
side of the road when traffic
conditions allow.
Trailer Tires
Special Trailer (ST) tires differ from vehicle
tires. Trailer tires are designed with stiff
sidewalls to help prevent sway and to support heavy loads. These features can
make it difficult to determine if the trailer
tire pressures are low only based on a visual
inspection.
Always check all trailer tire pressures before
each trip when the tires are cool. Low trailer
tire pressure is a leading cause of trailer tire
blowouts.
Trailer tires deteriorate over time. The trailer
tire sidewall will show the week and year
the tire was manufactured. Many trailer tire
manufacturers recommend replacing tires
more than six years old.
Overloading is another leading cause of
trailer tire blowouts. Never load your trailer
with more weight than the tires are
designed to support. The load rating is
located on the trailer tire sidewall.
Always know the maximum speed rating for
the trailer tires before driving. This may be
significantly lower than the vehicle tire
speed rating. The speed rating may be on
the trailer tire sidewall. If the speed rating is
not shown, the default trailer tire speed
rating is 105 km/h (65 mph).

GMC Canyon/Canyon Denali Owner Manual (GMNA-Localizing-U.S./Canada-
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248 Vehicle Care
Caution
Do not run the engine if there is a leak
in the engine cooling system. This can
cause a loss of all coolant and can
damage the system and vehicle. Have
any leaks fixed right away.
If the decision is made not to lift the hood
when this warning appears, get service help
right away.
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 and have the
vehicle serviced.
If Steam Is Coming from the Engine
Compartment
{Warning
Steam and scalding liquids from a hot
cooling system are under pressure.
Turning the pressure cap, even a little,
can cause them to come out at high (Continued)
Warning (Continued)
speed and you could be burned. Never
turn the cap when the cooling system,
including the pressure cap, is hot. Wait
for the cooling system and pressure cap
to 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 too 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 overheat zone, 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.
Engine Fan
If the vehicle has a clutched engine cooling
fan, when the clutch is engaged, the fan
spins faster to provide more air to cool the
engine. In most everyday driving conditions,
the fan is spinning slower and the clutch is
not fully engaged. This improves fuel
economy and reduces fan noise. Under
heavy vehicle loading, trailer towing, and/or
high outside temperatures, the fan speed
increases as the clutch more fully engages,
so an increase in fan noise may be heard.
This is normal and should not be mistaken
as the transmission slipping or making extra

GMC Canyon/Canyon Denali Owner Manual (GMNA-Localizing-U.S./Canada-
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Vehicle Care 249
shifts. It is merely the cooling system
functioning properly. The fan will slow down
when additional cooling is not required and
the clutch disengages.
This fan noise may also be heard when
starting the engine. It will go away as the
fan clutch partially disengages.
If the vehicle has electric cooling fan(s), the
fans may be heard spinning at low speed
during most everyday driving. The fans may
turn off if no cooling is required. Under
heavy vehicle loading, trailer towing, high
outside temperatures, or operation of the air
conditioning system, the fans may change
to high speed and an increase in fan noise
may be heard. This is normal and indicates
that the cooling system is functioning
properly. The fans will change to low speed
when additional cooling is no longer
required.
The electric engine cooling fans may run
after the engine has been turned. off. This is
normal and no service is required.Washer Fluid
What to Use
When windshield washer fluid needs to be
added, be sure to read the manufacturer's
instructions before use. Use a fluid that has
sufficient protection against freezing in an
area where the temperature may fall below
freezing.
Adding Washer Fluid
Open the cap with the washer symbol on it.
Add washer fluid until the tank is full. See
Engine Compartment Overview0237 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.
(Continued)
Caution (Continued)
.Do not use engine coolant (antifreeze)
in the windshield washer. It can
damage the windshield washer system
and paint.
.Do not mix water with ready-to-use
washer fluid. Water can cause the
solution to freeze and damage the
washer fluid tank and other parts of
the washer system.
.When using concentrated washer fluid,
follow the manufacturer instructions
for adding water.
.Fill the washer fluid tank only
three-quarters full when it is very cold.
This allows for fluid expansion if
freezing occurs, which could damage
the tank if it is completely full.
Brakes
Disc brake pads have built-in wear indicators
that make a high-pitched warning sound
when the brake pads are worn and new
pads are needed. The sound can come and
go or be heard all the time the vehicle is
moving, except when applying the brake
pedal firmly.

GMC Canyon/Canyon Denali Owner Manual (GMNA-Localizing-U.S./Canada-
14430430) - 2021 - CRC - 9/9/20
262 Vehicle Care
The vehicle may not be equipped with all of
the fuses, relays, and features shown.Fuses Usage
F1 Traction control module power
F2 Engine control module power
F3 Air conditioning clutch
F4 –
F5 Engine control module ignition/Integrated
chassis control module/
Fuel pump power
module
F6 Wipers F7 Cargo lamp/Bed lighting
F8 Fuel injectors –even
F9 Fuel injectors –odd
F10 Engine control module 1 F11 Oxygen/Mass air flow/ Humidity/Induction air
temperature/Throttle
inlet pressure sensors
F12 Starter Fuses
Usage
F13 Traction control module
F14 –
F15 –
F16 –
F17 Front axle actuator
F18 –
F19 Aeroshutters
F20 –
F21 Front blower
F22 Antilock brake system valves
F23 –
F24 Trailer F25 Transfer case electronic control
F26 Antilock brake system pump
F27 Trailer brake control module/Trailer wiring
provisions
F28 Rear window defogger Fuses
Usage
F29 –
F30 Driver heated seat F31 –
F32 Passenger heated seat
F33 Right headlamp low beam/Front right park
lamp/Right front side
marker/Right rear side
marker
F34 Fuel pump power module
F35 Integrated chassis control module
F36 Center high-mounted stoplamp
F37 Right high-beam headlamp
F38 Left high-beam headlamp
F39 –
F40 –
F41 –
F42 –

GMC Canyon/Canyon Denali Owner Manual (GMNA-Localizing-U.S./Canada-
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Vehicle Care 263
FusesUsage
F43 Not used
F44 –
F45 Vaccuum pump
F46 Engine control module 2 F47 Mid park phase lock/ Active fuel
management/Engine oil
and canister purge
solenoid(s)/Oxygen
sensor
F48 Fog lamps
F49 –
F50 Trailer parking lamps F51 Horn
F52 –
F53 –
F54 –
F55 –
F56 Washer pump F57 –
F58 – Fuses
Usage
F59 –
F60 Mirrors defogger F61 –
F62 Canister vent solenoid
F63 –
F64 Trailer reverse lamp F65 Left trailer stoplamp/ Turn signal lamps
F66 Right trailer stoplamp/ Turn signal lamps
F67 Electric power steering
F68 –
F69 Battery regulated voltage control
F70 –
F71 –
F72 –
F73 –
F74 Generator F75 – Relays
Usage
K1 Air conditioning clutch
K2 Starter
K3 –
K4 Wipers speed K5 Wipers control
K6 Cargo lamp/Bed lighting K7 Powertrain
K8 –
K9 –
K10 –
K11 Center high-mounted stoplamp
K12 –
K13 Vacuum pump
K14 Trailer parking lamps K15 Run/Crank
K16 –
K17 Rear window defogger

GMC Canyon/Canyon Denali Owner Manual (GMNA-Localizing-U.S./Canada-
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268 Vehicle Care
Passenger (P-Metric) Tire Example
(1) Tire Size:The tire size is a
combination of letters and numbers
used to define a particular tire's width,
height, aspect ratio, construction type,
and service description. See the “Tire
Size” illustration later in this section.
(2) TPC Spec (Tire Performance Criteria
Specification)
:Original equipment tires
designed to GM's specific tire
performance criteria have a TPC
specification code molded onto the
sidewall. GM's TPC specifications meet
or exceed all federal safety guidelines. (3) DOT (Department of
Transportation)
:The Department of
Transportation (DOT) code indicates that
the tire is in compliance with the U.S.
Department of Transportation Motor
Vehicle Safety Standards.
DOT Tire Date of Manufacture
:The last
four digits of the TIN indicate the tire
manufactured date. The first two digits
represent the week and the last two
digits, the year. For example, the third
week of the year 2020 would have a
four-digit DOT date of 0320. Week 01 is
the first full week (Sunday through
Saturday) of each year.
(4) Tire Identification Number (TIN)
:
The letters and numbers following the
DOT (Department of Transportation)
code are the Tire Identification Number
(TIN). The TIN shows the manufacturer
and plant code, tire size, and date the
tire was manufactured. The TIN is
molded onto both sides of the tire,
although only one side may have the
date of manufacture. (5) Tire Ply Material
:The type of cord
and number of plies in the sidewall and
under the tread.
(6) Uniform Tire Quality Grading
(UTQG)
:Tire manufacturers are
required to grade tires based on three
performance factors: treadwear,
traction, and temperature resistance.
For more information see Uniform Tire
Quality Grading 0280.
(7) Maximum Cold Inflation Load
Limit
:Maximum load that can be
carried and the maximum pressure
needed to support that load.
(8) Temporary Use Only
:Only use a
temporary spare tire until the road tire
is repaired and replaced. This spare tire
should not be driven on over 112 km/h
(70 mph), or 88 km/h (55 mph) when
pulling a trailer, with the proper
inflation pressure. See Full-Size Spare
Tire 0293.

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Vehicle Care 293
When using a compact spare tire, the AWD
(if equipped), ABS, and Traction Control
systems may engage until the spare tire is
recognized by the vehicle, especially on
slippery roads. Adjust driving to reduce
possible wheel slip.
Caution
When the compact spare is installed, do
not take the vehicle through an
automatic car wash with guide rails. The
compact spare can get caught on the rails
which can damage the tire, wheel, and
other parts of the vehicle.
Do not use the compact spare on other
vehicles.
Do not mix the compact spare tire or wheel
with other wheels or tires. They will not fit.
Keep the spare tire and its wheel together.
Caution
Tire chains will not fit the compact spare.
Using them can damage the vehicle and
the chains. Do not use tire chains on the
compact spare.
Full-Size Spare Tire
If this vehicle came with a full-size spare
tire, it was fully inflated when new,
however, it can lose air over time. Check the
inflation pressure regularly. See Tire Pressure
0 272 and
Vehicle Load Limits 0180 for information
regarding proper tire inflation and loading
the vehicle. For instructions on how to
remove, install, or store a spare tire, see Tire
Changing 0284.
If equipped with a temporary use full-size
spare tire, it is indicated on the tire sidewall.
See Tire Sidewall Labeling 0267. This spare
tire should not be driven on over 112 km/h
(70 mph), or 88 km/h (55 mph) when
pulling a trailer, at the proper inflation
pressure. Repair and replace the road tire as
soon as it is convenient, and stow the spare
tire for future use.
Caution
If the vehicle has four-wheel drive and a
different size spare tire is installed, do
not drive in four-wheel drive until the flat
tire is repaired and/or replaced. The
vehicle could be damaged and the repairs
(Continued)
Caution (Continued)
would not be covered by the warranty.
Never use four-wheel drive when a
different size spare tire is installed on the
vehicle.
The vehicle may have a different size spare
tire than the road tires originally installed
on the vehicle. This spare tire was developed
for use on this vehicle, so it is all right to
drive on it. If the vehicle has four-wheel
drive and a different size spare tire is
installed, drive only in two-wheel drive.
After installing the spare tire on the vehicle,
stop as soon as possible and check that the
spare is correctly inflated. The spare tire is
made to perform well at speeds up to
112 km/h (70 MPH) at the recommended
inflation pressure, so you can finish
your trip.
Have the damaged or flat road tire repaired
or replaced and installed back onto the
vehicle as soon as possible so the spare tire
will be available in case it is needed again.
Do not mix tires and wheels of difference
sizes, because they will not fit. Keep the
spare tire and its wheel together.