light GMC SAVANA 2018 Repair Manual

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
Driving and Operating 187
intended path. Trailer Sway Control
(TSC) is also on automatically when
the vehicle is started. SeeTrailer
Sway Control (TSC) 0209.
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 0166
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
dcomes 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
dcomes on and stays on:
1. Stop the vehicle. 2. Turn the engine off and wait
15 seconds.
3. Start the engine.
Drive the vehicle. If
dcomes 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

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
188 Driving and Operating
Caution
Do not repeatedly brake or
accelerate heavily when TCS is
off. The vehicle driveline could be
damaged.
To turn off only TCS, press and
release
g. The appropriate
message will display in the DIC. To
turn TCS on again, press and
release
g.
If TCS is limiting wheel spin when
g
is pressed, the system will not turn
off until the wheels stop spinning.
To turn off both TCS and StabiliTrak,
press and hold
guntil the
StabiliTrak OFF light
gcomes on
and stays on in the instrument
cluster, then release. The
appropriate message will display in
the DIC. To turn TCS and StabiliTrak on
again, press and release
g. The
StabiliTrak OFF light
gin the
instrument cluster turns off.
StabiliTrak will automatically turn
back on if the vehicle exceeds
32 km/h (20 mph). TCS will remain
off until
gis pressed or the ignition
is cycled off then on.
The vehicle has a Trailer Sway
Control (TSC) feature and a Hill
Start Assist (HSA) feature.
See Trailer Sway Control (TSC)
0 209 orHill Start Assist (HSA)
0 186. Adding accessories can affect the
vehicle performance. See
Accessories and Modifications
0
213.
Locking Rear Axle
Vehicles with a locking rear axle can
give more traction on snow, mud,
ice, sand, or gravel. It works like a
standard axle most of the time, but
when traction is low, this feature will
allow the rear wheel with the most
traction to move the vehicle.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
Driving and Operating 191
when driving on downhill grades by
using the engine and transmission
to slow the vehicle.
If the brake pedal is applied, cruise
control will disengage.
Ending Cruise Control
There are four ways to end cruise
control:
.Step lightly on the brake pedal.
. Press
[.
. Shift the transmission to
N (Neutral).
. To turn off cruise control,
press
I.
Erasing Speed Memory
The cruise control set speed is
erased from memory if
Iis
pressed or if the vehicle is
turned off.
Driver Assistance
Systems
Rear Vision
Camera (RVC)
If equipped, the RVC system is
designed to help the driver when
backing up by displaying a view of
the area behind the vehicle.
{Warning
The camera(s) do not display
children, pedestrians, bicyclists,
crossing traffic, animals, or any
other object outside of the
cameras’ field of view, below the
bumper, or under the vehicle.
Shown distances may be different
from actual distances. Do not
drive or park the vehicle using
only these camera(s). Always
check behind and around the
vehicle before driving. Failure to
use proper care may result in
injury, death, or vehicle damage. When the vehicle is on and shifted
into R (Reverse), the video image
appears on the inside rearview
mirror. The video image disappears
after the vehicle is shifted out of
R (Reverse).
RVC Location
The camera is next to the license
plate.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
Driving and Operating 193
How the System Works
RPA comes on automatically when
the shift lever is moved into
R (Reverse). A single beep sounds
to indicate the system is working.
RPA operates only at speeds less
than 8 km/h (5 mph).
An obstacle detection is indicated
by beeps. The time between beeps
gets shorter as the vehicle
approaches the obstacle. Repeated
beeps are heard when the distance
is less than 30 cm (12 in).
To be detected, objects must be at
least 25 cm (10 in) off the ground
and below rear door level. Objects
must also be within 2.5 m (8 ft) from
the rear bumper. This distance may
be less during warmer or humid
weather.
Turning the System On and Off
The system can be disabled through
the Driver Information Center (DIC).
See“Park Assist” underDriver
Information Center (DIC) 0109.
RPA defaults to the on setting each
time the vehicle is started. Turn RPA off when towing a trailer.
When the System Does Not
Seem to Work Properly
The following messages may be
displayed on the DIC:
SERVICE PARK ASSIST :
If this
message occurs, take the vehicle to
your dealer for repair.
PARK ASSIST OFF : This message
occurs if the driver disables the
system or if the vehicle is driven
above 8 km/h (5 mph) in
R (Reverse).
PARK ASST BLOCKED SEE
OWNERS MANUAL : This
message can occur under the
following conditions:
. The sensors are not clean. Keep
the rear bumper free of mud,
dirt, snow, ice, slush, and frost.
The message may not clear until
frost or ice has melted all around
and inside the sensor.
. A trailer is attached to the
vehicle, or a bicycle or an object
hanging out of the rear door
during the current or last drive cycle. RPA will return to normal
operation after it is determined
the object is removed. This
could take a few drive cycles.
. A tow bar is attached to the
vehicle.
Other conditions may affect system
performance, such as vibrations
from a jackhammer or the
compression of air brakes on a very
large truck.
Side Blind Zone
Alert (SBZA)
If equipped, the SBZA system is a
lane-changing aid that assists
drivers with avoiding crashes that
occur with moving vehicles in the
side blind zone (or spot) areas. The
SBZA warning display will light up in
the corresponding outside side
mirror and will flash if the turn signal
is on.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
194 Driving and Operating
{Warning
SBZA does not alert the driver to
vehicles rapidly approaching
outside of the side blind zones,
pedestrians, bicyclists,
or animals. It may not provide
alerts when changing lanes under
all driving conditions. Failure to
use proper care when changing
lanes may result in injury, death,
or vehicle damage. Before
making a lane change, always
check mirrors, glance over your
shoulder, and use the turn
signals.SBZA Detection Zones
The SBZA sensor covers a zone of
approximately one lane over from
both sides of the vehicle, or 3.5 m
(11 ft). The height of the zone is
approximately between 0.5 m (1.5 ft)
and 2 m (6 ft) off the ground. This
zone starts at approximately the
middle of the vehicle and goes back
8 m (26 ft).
How the System Works
The SBZA symbol lights up in the
side mirrors when the system
detects a moving vehicle in the next lane over that is in the side blind
zone. This indicates it may be
unsafe to change lanes. Before
making a lane change, check the
SBZA display, check mirrors, glance
over your shoulder, and use the turn
signals.
Left Side Mirror
DisplayRight Side Mirror Display
When the vehicle is started, both
outside mirror SBZA displays will
briefly come on to indicate the
system is operating. When the
vehicle is in a forward gear, the left
or right side mirror display will light
up if a moving vehicle is detected in
that blind zone. If the turn signal is
activated in the same direction of a
detected vehicle, this display will
flash as an extra warning not to
change lanes.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
Driving and Operating 195
SBZA can be disabled through the
Driver Information Center (DIC).
SeeDriver Information Center (DIC)
0 109. If SBZA is disabled by the
driver, the SBZA mirror displays will
not light up.
When the System Does Not
Seem to Work Properly
SBZA displays may not come on
when passing a vehicle quickly, for
a stopped vehicle, or when towing a
trailer. The SBZA detection zones
that extend back from the side of
the vehicle do not move further back
when a trailer is towed. Use caution
while changing lanes when towing a
trailer. SBZA may alert to objects
attached to the vehicle, such as a
trailer, bicycle, or object extending
out to either side of the vehicle. This
is normal system operation; the
vehicle does not need service.
SBZA may not always alert the
driver to vehicles in the side blind
zone, especially in wet conditions.
The system does not need to be
serviced. The system may light up
due to guardrails, signs, trees, shrubs, and other non-moving
objects. This is normal system
operation; the vehicle does not need
service.
SBZA may not operate when the
SBZA sensors in the left or right
corners of the rear bumper are
covered with mud, dirt, snow, ice,
or slush, or in heavy rainstorms. For
cleaning instructions, see "Washing
the Vehicle" under
Exterior Care
0 290. If the DIC displays the
system unavailable message after
cleaning both sides of the vehicle
toward the rear corners of the
vehicle, see your dealer.
If the SBZA displays do not light up
when vehicles are in the blind zone
and the system is clean, the system
may need service. Take the vehicle
to your dealer.
Radio Frequency Information
See Radio Frequency Statement
0 326.
Fuel
For diesel engine vehicles, see
“Fuel for Diesel Engines” in the
Duramax diesel supplement.
GM recommends the use of TOP
TIER
®detergent gasoline to keep
the engine cleaner and reduce
engine deposits. See
www.toptiergas.com for a list of TOP
TIER detergent gasoline marketers
and applicable countries.
If the vehicle has a yellow fuel cap
or a yellow sticker on the fuel door,
E85 or FlexFuel can be used. See
E85 or FlexFuel 0197.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
196 Driving and Operating
Use regular unleaded gasoline
meeting ASTM specification D4814
with a posted octane rating of 87 or
higher. Do not use gasoline with a
posted octane rating of less than 87,
as this may cause engine knock and
will lower fuel economy.
Prohibited Fuels
Caution
Do not use fuels with any of the
following conditions; doing so
may damage the vehicle and void
its warranty:. For vehicles which are not
FlexFuel, fuel labeled
greater than 15% ethanol by
volume, such as mid-level
ethanol blends (16 –50%
ethanol), E85, or FlexFuel.
. Fuel with any amount of
methanol, methylal, and
aniline. These fuels can
corrode metal fuel system
parts or damage plastic and
rubber parts.
(Continued)
Caution (Continued)
.Fuel containing metals such
as methylcyclopentadienyl
manganese tricarbonyl
(MMT), which can damage
the emissions control
system and spark plugs.
. Fuel with a posted octane
rating of less than the
recommended fuel. Using
this fuel will lower fuel
economy and performance,
and may decrease the life of
the emissions catalyst.
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 may 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) 0103. 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
The U.S., Canada, and Mexico post
fuel octane ratings in anti-knock
index (AKI). For fuel not to use in a
foreign country, see “Prohibited
Fuels” inFuel 0195.
Fuel Additives
To keep fuel systems clean, TOP
TIER detergent gasoline is
recommended. See Fuel0195.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
Driving and Operating 199
When replacing the fuel cap, turn it
clockwise until it clicks. Make sure
the cap is fully installed. The
diagnostic system can determine if
the fuel cap has been left off or
improperly installed. This would
allow fuel to evaporate into the
atmosphere. SeeMalfunction
Indicator Lamp (Check Engine
Light) 0103.
{Warning
If a fire starts while you are
refueling, do not remove the
nozzle. Shut off the flow of fuel by
shutting off the pump or by
notifying the station attendant.
Leave the area immediately.
Caution
If a new fuel cap is needed, be
sure to get the right type of cap
from your dealer. The wrong type
of fuel cap may not fit properly,
(Continued)
Caution (Continued)
may cause the malfunction
indicator lamp to light, and could
damage the fuel tank and
emissions system. See
Malfunction Indicator Lamp
(Check Engine Light)0103.
Filling a Portable Fuel
Container
{Warning
Filling a portable fuel container
while it is in the vehicle can cause
fuel vapors that can ignite either
by static electricity or other
means. You or others could be
badly burned and the vehicle
could be damaged. Always:
. Use approved fuel
containers.
(Continued)
Warning (Continued)
.Remove the container from
the vehicle, trunk, or pickup
bed before filling.
. Place the container on the
ground.
. Place the nozzle inside the
fill opening of the container
before dispensing fuel, and
keep it in contact with the fill
opening until filling is
complete.
. Fill the container no more
than 95% full to allow for
expansion.
. Do not smoke, light
matches, or use lighters
while pumping fuel.
. Avoid using cell phones or
other electronic devices.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
208 Driving and Operating
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.
Do not tap into the vehicle's
hydraulic brake system.
Trailer Wiring Harness
The optional heavy-duty trailer
wiring package includes a wiring
harness, with a seven-pin connector
at the rear of the vehicle and a
four-wire harness assembly under
the driver side of the instrument
panel. The four-wire harness
assembly comes without a
connector.
If the vehicle does not have a trailer
hitch, the seven-wire harness
assembly with connector is taped
together and located in a frame
pocket at the driver side rear left
corner of the frame.If the vehicle has a trailer hitch, the
seven-wire harness assembly with
connector is attached to a bracket
on the hitch platform. In both cases,
the seven-wire harness has a
connector and includes a 30-amp
feed wire.
Use only a round, seven-wire
connector with flat blade terminals
meeting SAE J2863 specifications
for proper electrical connectivity.
The seven-wire harness connector
contains the following trailer circuits:
.
Light Green: Back-up Lamps
(10A fuse)**
. White: Ground
. Dark Blue: Trailer Brake Signal
. Dark Green: Right Rear Stop
and Turn Signal*
. Red/Black Stripe: Battery Feed
(30A Fuse)
. Brown: Trailer Park Lamp
Supply Voltage (15A fuse)**
. Yellow: Left Rear Stop and Turn
Signal * The four-wire harness (without
connector) contains the following
circuits:
.
Black: Ground
. Red/White: Battery Feed
. Dark Blue: Trailer Brake Signal
. Light Blue: CHMSL/Stoplamp
Supply Voltage
* If the vehicle is a cutaway with
trailer provisions, a 15 amp fuse will
be shared for both left/stop trailer
turn and right/stop trailer turn
signals. However, the cutaway
lighting connector will have a
10 amp fuse for each signal.
** If the vehicle is a cutaway with
trailer provisions, a 15 amp fuse will
be shared for trailer park lamps and
cutaway rear lighting connector park
lamps. Also, a 10 amp fuse will be
shared for trailer back-up lamps and
cutaway rear lighting connector
back-up lamps.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
Driving and Operating 209
Tow/Haul Mode
This button is on the instrument
panel, to the right of the steering
wheel.
Pressing this button turns on and off
the Tow/Haul Mode.
This indicator light on the instrument
cluster comes on when the Tow/
Haul Mode is on.
Tow/Haul is a feature that assists
when pulling a heavy trailer or a
large or heavy load. SeeTow/Haul
Mode 0184.
Tow/Haul is designed to be most
effective when the vehicle and
trailer combined weight is at least
75 percent of the vehicle Gross
Combined Weight Rating (GCWR). See
“Weight of the Trailer” inTrailer
Towing 0202. Tow/Haul is most
useful under the following driving
conditions:
. When pulling a heavy trailer or a
large or heavy load through
rolling terrain.
. When pulling a heavy trailer or a
large or heavy load in
stop-and-go traffic.
. When pulling a heavy trailer or a
large or heavy load in busy
parking lots where improved low
speed control of the vehicle is
desired.
Operating the vehicle in Tow/Haul
Mode when lightly loaded or with no
trailer at all will not cause damage.
However, there is no benefit to the
selection of Tow/Haul when the
vehicle is unloaded. Such a
selection when unloaded may result
in unpleasant engine and
transmission driving characteristics
and reduced fuel economy. Tow/
Haul is recommended only when
pulling a heavy trailer or a large or
heavy load.
Trailer Sway
Control (TSC)
Trailer sway is unintended
side-to-side motion of a trailer while
being towed. 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.
When TSC is active, the Traction
Control System (TCS)/StabiliTrak
warning light will flash on the
instrument cluster. Vehicle speed
must be reduced. If trailer sway
continues, StabiliTrak can reduce
engine torque to help slow the
vehicle. See Traction Control/
Electronic Stability Control 0186.
{Warning
Even if the vehicle is equipped
with TSC, trailer sway could result
in loss of control and the vehicle
could crash. If excessive trailer
sway is detected, slow down to a
(Continued)