2018 GMC TERRAIN wiring

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-10664916) - 2018 - crc - 9/15/17
86 Seats and Restraints
A thick layer of additional material,
such as a blanket or cushion,
or aftermarket equipment such as
seat covers, seat heaters, and seat
massagers can affect how well the
passenger sensing system
operates. We recommend that you
not use seat covers or other
aftermarket equipment except when
approved by GM for your specific
vehicle. SeeAdding Equipment to
the Airbag-Equipped Vehicle 086
for more information about
modifications that can affect how
the system operates.
The on indicator may be lit if an
object, such as a briefcase,
handbag, grocery bag, laptop,
or other electronic device, is put on
an unoccupied seat. If this is not
desired, remove the object from
the seat.
{Warning
Stowing articles under the
passenger seat or between the
passenger seat cushion and
(Continued)
Warning (Continued)
seatback may interfere with the
proper operation of the passenger
sensing system.
Servicing the
Airbag-Equipped Vehicle
Airbags affect how the vehicle
should be serviced. There are parts
of the airbag system in several
places around the vehicle. Your
dealer and the service manual have
information about servicing the
vehicle and the airbag system. To
purchase a service manual, see
Service Publications Ordering
Information0378.
{Warning
For up to 10 seconds after the
vehicle is turned off and the
battery is disconnected, an airbag
can still inflate during improper
service. You can be injured if you
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Warning (Continued)
are close to an airbag when it
inflates. Avoid yellow connectors.
They are probably part of the
airbag system. Be sure to follow
proper service procedures, and
make sure the person performing
work for you is qualified to do so.
Adding Equipment to the
Airbag-Equipped Vehicle
Adding accessories that change the
vehicle's frame, bumper system,
height, front end, or side sheet
metal may keep the airbag system
from working properly. The
operation of the airbag system can
also be affected by changing any
parts of the front seats, seat belts,
airbag sensing and diagnostic
module, steering wheel, instrument
panel, inner door seals including the
speakers, any of the airbag
modules, ceiling or pillar garnish
trim, overhead console, front
sensors, side impact sensors,
or airbag wiring.

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-10664916) - 2018 - crc - 9/15/17
Seats and Restraints 87
Your dealer and the service manual
have information about the location
of the airbag sensors, sensing and
diagnostic module, and airbag
wiring.
In addition, the vehicle has a
passenger sensing system for the
front outboard passenger position,
which includes sensors that are part
of the passenger seat. The
passenger sensing system may not
operate properly if the original seat
trim is replaced with non-GM
covers, upholstery, or trim; or with
GM covers, upholstery, or trim
designed for a different vehicle. Any
object, such as an aftermarket seat
heater or a comfort-enhancing pad
or device, installed under or on top
of the seat fabric, could also
interfere with the operation of the
passenger sensing system. This
could either prevent proper
deployment of the passenger
airbag(s) or prevent the passenger
sensing system from properly
turning off the passenger airbag(s).
SeePassenger Sensing System
0 82. If the vehicle has rollover roof-rail
airbags, see
Different Size Tires
and Wheels 0317 for additional
important information.
If you have to modify your vehicle
because you have a disability and
have questions about whether the
modifications will affect the vehicle's
airbag system, or if you have
questions about whether the airbag
system will be affected if the vehicle
is modified for any other reason, call
Customer Assistance. See
Customer Assistance Offices 0371.
Airbag System Check
The airbag system does not need
regularly scheduled maintenance or
replacement. Make sure the airbag
readiness light is working. See
Airbag Readiness Light 0126.
Caution
If an airbag covering is damaged,
opened, or broken, the airbag
may not work properly. Do not
(Continued)
Caution (Continued)
open or break the airbag
coverings. If there are any
opened or broken airbag
coverings, have the airbag
covering and/or airbag module
replaced. For the location of the
airbags, seeWhere Are the
Airbags? 078. See your dealer
for service.
Replacing Airbag System
Parts after a Crash
{Warning
A crash can damage the airbag
systems in the vehicle.
A damaged airbag system may
not properly protect you and your
passenger(s) in a crash, resulting
in serious injury or even death. To
help make sure the airbag
systems are working properly
after a crash, have them
(Continued)

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-10664916) - 2018 - crc - 9/15/17
126 Instruments and Controls
such as a briefcase, handbag,
grocery bag, laptop, or other
electronic device. To turn off the
reminder light and/or chime, remove
the object from the seat or buckle
the seat belt.
Airbag Readiness Light
This light shows if there is an
electrical problem with the airbag
system. The system check includes
the airbag sensor(s), the passenger
sensing system, the pretensioners,
the airbag modules, the wiring, and
the crash sensing and diagnostic
module. For more information on the
airbag system, seeAirbag System
0 76.
The airbag readiness light comes on
for several seconds when the
vehicle is started. If the light does
not come on then, have it fixed
immediately.
{Warning
If the airbag readiness light stays
on after the vehicle is started or
comes on while driving, it means
the airbag system might not be
working properly. The airbags in
the vehicle might not inflate in a
crash, or they could even inflate
without a crash. To help avoid
injury, have the vehicle serviced
right away.
If there is a problem with the airbag
system, a Driver Information Center
(DIC) message may also come on.
Passenger Airbag Status
Indicator
The vehicle has a passenger
sensing system. See Passenger
Sensing System 082 for important safety information. The overhead
console has a passenger airbag
status indicator.
When the vehicle is started, the
passenger airbag status indicator
will light ON and OFF for several
seconds as a system check. Then,
after several more seconds, the
status indicator will light either ON
or OFF to let you know the status of
the front outboard passenger frontal
airbag.
If the word ON is lit on the
passenger airbag status indicator, it
means that the front outboard
passenger frontal airbag is allowed
to inflate.

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-10664916) - 2018 - crc - 9/15/17
Vehicle Care 275
To inspect or replace the engine air
cleaner/filter:
1.5L Gas Engine Shown, 1.6LDiesel Engine and 2.0L Gas Engine Similar
1. Screws
2. Air Duct Clamp
3. Electrical Connector
1. Open the hood. See Hood
0 262.
2. Loosen the screw on the air duct clamp (2) and remove the
air duct hose from the cover. 3. Remove the four screws (1)
and remove the air cleaner/
filter cover, keeping the wiring
harness electrical connector (3)
connected to the sensor.
4. Pull straight up on the cover, and while holding the cover,
remove the air cleaner/filter.
5. Inspect or replace the air cleaner/filter.
How to Reinstall the Engine
Air Cleaner/Filter
1. Align the air cleaner/filter withthe indicated point on the base
of the air cleaner/filter housing and install the air cleaner/filter.
The outer air cleaner/filter seal
must be fitted properly in the
air cleaner/filter housing.
2. Align the air cleaner/filter housing cover tabs to the air
cleaner/filter housing.
3. Install the air cleaner/filter housing cover using the four
screws.
4. Slide the air duct onto the cover assembly and tighten the
screw on the air duct clamp.
5. Verify that the wiring harness connector is fully connected to
the sensor on the air cleaner/
filter housing.
{Warning
Operating the engine with the air
cleaner/filter off can cause you or
others to be burned. The air
cleaner not only cleans the air; it
helps to stop flames if the engine
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GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-10664916) - 2018 - crc - 9/15/17
290 Vehicle Care
2. Remove the bulb access capfrom the top of the headlamp
assembly by turning it
counterclockwise.
3. Remove the bulb from the bulbsocket by pinching the tabs on
either side of the bulb and pull
straight out.
4. Install the new bulb in the bulb socket.
5. Install the bulb access cap onto the headlamp assembly by
turning clockwise.
Taillamps
To replace one of these lamps:
1. Open the liftgate. See Liftgate
0 41.
2. Remove the two screw caps
and two screws from the
taillamp assembly.
3. Pull the taillamp assembly out of the vehicle body.
4. Disconnect the lamp wiring harness.
5. Turn the bulb socketcounterclockwise and pull
it out.
6. Pull the bulb straight out of the socket.
7. Push the replacement bulb straight into the bulb socket.

GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-10664916) - 2018 - crc - 9/15/17
292 Vehicle Care
Electrical System
Electrical System
Overload
The vehicle has fuses and circuit
breakers to protect against an
electrical system overload.
When the electrical load current is
too heavy, the circuit breaker opens
and closes, protecting the circuit
until the current load returns to
normal or the problem is fixed. This
greatly reduces the chance of circuit
overload and fire caused by
electrical problems.
Replace a bad fuse with a new one
of the identical size and rating.
If there is a problem on the road and
a fuse needs to be replaced, the
same amperage fuse can be
borrowed. Choose some feature of
the vehicle that is not needed to use
and replace it as soon as possible.
Headlamp Wiring
An electrical overload may cause
the lamps to go on and off, or in
some cases to remain off. Have the
headlamp wiring checked right away
if the lamps go on and off or
remain off.
Windshield Wipers
If the wiper motor overheats due to
heavy snow or ice, the windshield
wipers will stop until the motor cools
and will then restart.
Although the circuit is protected
from electrical overload, overload
due to heavy snow or ice may
cause wiper linkage damage.
Always clear ice and heavy snow
from the windshield before using the
windshield wipers.
If the overload is caused by an
electrical problem and not snow or
ice, be sure to get it fixed.
Fuses and Circuit
Breakers
The wiring circuits in the vehicle are
protected from short circuits by a
combination of fuses and circuit
breakers. This greatly reduces the
chance of damage caused by
electrical problems.
{Danger
Fuses and circuit breakers are
marked with their ampere rating.
Do not exceed the
specified amperage rating when
replacing fuses and circuit
breakers. Use of an oversized
fuse or circuit breaker can result
in a vehicle fire. You and others
could be seriously injured or
killed.
To check a fuse, look at the
silver-colored band inside the fuse.
If the band is broken or melted,
replace the fuse. Be sure to replace
a bad fuse with a new one of the
identical size and rating.