2018 GMC ACADIA service electrical parking

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
Driving and Operating 277
becomes separated from the hitch.
Always leave just enough slack so
the rig can turn. Never allow safety
chains to drag on the ground.
Trailer Brakes
A loaded trailer that weighs more
than 450 kg (1,000 lb) must be
equipped with its own brake system,
with brakes working on all axles.
Trailer braking equipment
conforming to Canadian Standards
Association (CSA) requirement
CAN3-D313, or its equivalent, is
recommended.
State and local regulations may also
require the trailer to have its own
braking system if loaded above a
certain threshold. These
requirements vary from state to
state.
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
hydraulic brake system. If you do,
both brake systems will not work
well, or at all.Trailer Wiring Harness
Basic Trailer Wiring
The trailer wiring harness, with a
seven-pin connector, is located at
the rear of the vehicle and is tied to
the vehicle's frame. The harness
connector can be plugged into a
seven-pin universal heavy-duty
trailer connector available through
your dealer.
Use only a round, seven-wire
connector with flat blade terminals
meeting SAE J2863 specifications
for proper electrical connectivity.
The seven-wire harness contains
the following trailer circuits:
.
Yellow/Gray: Stop/Turn
Signal Left
. Green/Violet: Stop/Turn Signal
Right
. Gray/Brown: Parking Lamps .
White/Green: Back-up Lamps
. Red/Green: Back-up Lamps
. Black: Ground
. Blue: Electric Brake*
*The fuse for this circuit is installed
in the underhood electrical center,
but the wires are not connected.
They should be connected by your
dealer or a qualified service center.
If the back-up lamp circuit is not
functional, contact your dealer.
If a remote (non-vehicle) battery is
being charged, turn the Tow/Haul
Mode knob on the center console.
This will boost the vehicle system
voltage and properly charge the
battery. If the trailer is too light for
Tow/Haul Mode, turn on the
headlamps (non-HID only) as a
second way to boost the vehicle
system and charge the battery.
Electric Trailer Brake Control
Wiring Provisions
These wiring provisions for an
electric trailer brake controller are
included with the vehicle as part of

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
278 Driving and Operating
the trailer wiring package. The
instrument panel contains blunt cut
wires above the parking brake
assembly for the electric trailer
brake controller. The harness
contains the following wires:
.Blue: “To Trailer”
. Red/Black or Red/Blue:
Battery Feed
. White/Blue: Brake Apply Signal
. Black: Ground
The electric trailer brake controller
should be installed by your dealer or
a qualified service center.Conversions and
Add-Ons
Add-On Electrical
Equipment
{Warning
The Data Link Connector (DLC)
is used for vehicle service
and Emission Inspection/
Maintenance testing. See
Malfunction Indicator Lamp
(Check Engine Light) 0136.
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.
Caution
Some 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 089 and Adding Equipment
to the Airbag-Equipped Vehicle
0 90.

GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
406 OnStar
Global Positioning
System (GPS)
.Obstruction of the GPS can
occur in a large city with tall
buildings; in parking garages;
around airports; in tunnels and
underpasses; or in an area with
very dense trees. If GPS signals
are not available, the OnStar
system should still operate to
call OnStar. However, OnStar
could have difficulty identifying
the exact location.
. In emergency situations, OnStar
can use the last stored GPS
location to send to emergency
responders.
A temporary loss of GPS can cause
loss of the ability to send a
Turn-by-Turn Navigation route. The
Advisor may give a verbal route or
may ask for a call back after the
vehicle is driven into an open area.
Cellular and GPS Antennas
Cellular reception is required for
OnStar to send remote signals to
the vehicle. Do not place items over or near the antenna to prevent
blocking cellular and GPS signal
reception.
Unable to Connect to OnStar
Message
If there is limited cellular coverage
or the cellular network has reached
maximum capacity, this message
may come on. Press
Qto try the
call again or try again after driving a
few miles into another cellular area.
Vehicle and Power Issues
OnStar services require a vehicle
electrical system, wireless service,
and GPS satellite technologies to be
available and operating for features
to function properly. These systems
may not operate if the battery is
discharged or disconnected.
Add-on Electrical Equipment
The OnStar system is integrated
into the electrical architecture of the
vehicle. Do not add any electrical
equipment. See Add-On Electrical
Equipment 0278. Added electrical equipment may interfere with the
operation of the OnStar system and
cause it to not operate.
Vehicle Software Updates
OnStar or GM may remotely deliver
software updates or changes to the
vehicle without further notice or
consent. These updates or changes
may enhance or maintain safety,
security, or the operation of the
vehicle or the vehicle systems.
Software updates or changes may
affect or erase data or settings that
are stored in the vehicle, such as
OnStar Hands-Free Calling name
tags, saved navigation destinations,
or pre-set radio stations. Neither
OnStar nor GM is responsible for
any affected or erased data or
settings. These updates or changes
may also collect personal
information. Such collection is
described in the OnStar privacy
statement or separately disclosed at
the time of installation. These
updates or changes may also cause
a system to automatically
communicate with GM servers to
collect information about vehicle