check engine light GMC SAVANA 2021 User Guide

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-14583543) -
2021 - crc - 7/10/20
Driving and Operating 145
Caution
Spinning the tires or holding the vehicle
in one place on a hill using only the
accelerator pedal may damage the
transmission. The repair will not be
covered by the vehicle warranty. If the
vehicle is stuck, do not spin the tires.
When stopping on a hill, use the brakes
to hold the vehicle in place.
Tow/Haul Mode
If equipped, Tow/Haul Mode adjusts the
transmission shift pattern to reduce shift
cycling, providing increased performance,
vehicle control, and transmission cooling
when towing or hauling heavy loads.
Turn the Tow/Haul Mode on and off by
pressing the button on the instrument
panel. When Tow/Haul is on, a light on the
instrument cluster will come on.
SeeTow/Haul Mode Light 078.
Also see “Tow/Haul Mode” underTowing
Equipment 0172.
Tow/Haul Mode Grade Braking
Tow/Haul Mode Grade Braking is only
enabled while the Tow/Haul Mode is
selected and the vehicle is not in the Range
Selection Mode. See “Tow/Haul Mode”listed
previously and Manual Mode0144. Tow/
Haul Mode Grade Braking assists in
maintaining desired vehicle speeds when
driving on downhill grades by using the
engine and transmission to slow the vehicle.
To disable or enable Tow/Haul Mode Grade
Braking within the current ignition key cycle,
press and hold the Tow/Haul button for
three seconds.
See Towing Equipment 0172. For other forms of grade braking, see
Automatic Transmission
0142.
Brakes
Antilock Brake System (ABS)
The Antilock Brake System (ABS) helps
prevent a braking skid and maintain steering
while braking hard.
ABS performs a system check when the
vehicle is first driven. A momentary motor
or clicking noise may be heard while this
test is going on, and the brake pedal may
move slightly. This is normal.
If there is a problem with ABS, this warning
light stays on. See Antilock Brake System
(ABS) Warning Light 078.
ABS does not change the time needed to
get a foot on the brake pedal and does not
always decrease stopping distance. If you
get too close to the vehicle ahead, there will
not be enough time to apply the brakes if

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-14583543) -
2021 - crc - 7/10/20
Driving and Operating 147
Warning (Continued)
driving may result in injury, death,
or vehicle damage. SeeDefensive Driving
0 126.
When the vehicle is stopped on a grade, Hill
Start Assist (HSA) temporarily prevents the
vehicle from rolling in an unintended
direction during the transition from brake
pedal release to accelerator pedal apply. The
brakes release when the accelerator pedal is
applied or automatically release after a few
seconds. The brakes may also release under
other conditions. Do not rely on HSA to hold
the vehicle.
HSA is available when the vehicle is facing
uphill in a forward gear, or when facing
downhill in R (Reverse). The vehicle must
come to a complete stop on a grade for HSA
to activate.
Ride Control Systems
Traction Control/Electronic
Stability Control
System Operation
The vehicle has a Traction Control System
(TCS) and StabiliTrak/Electronic Stability
Control (ESC), an electronic stability control
system. These systems help limit wheel spin
and assist the driver in maintaining control,
especially on slippery road conditions.
TCS activates if it senses any of the drive
wheels are spinning or beginning to lose
traction. When this happens, TCS applies the
brakes to the spinning wheels and reduces
engine power to limit wheel spin.
StabiliTrak/ESC activates when the vehicle
senses a difference between the intended
path and the direction the vehicle is actually
traveling. StabiliTrak/ESC selectively applies
braking pressure to any one of the vehicle
wheel brakes to assist the driver in keeping
the vehicle on the intended path. Trailer
Sway Control (TSC) is also on automatically
when the vehicle is started. See Trailer Sway
Control (TSC) 0175. If cruise control is being used and traction
control or StabiliTrak/ESC 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 0131 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/ESC is activated.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-14583543) -
2021 - crc - 7/10/20
Driving and Operating 159
Warning (Continued)
.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.
.Avoid using electronic devices while
refueling.
.Do not re-enter the vehicle while
pumping fuel.
.Keep children away from the fuel
pump and never let children
pump fuel.
.Before touching the fill nozzle, touch a
metallic object to discharge static
electricity from your body.
.Fuel can spray out if the fuel cap is
opened too quickly. This spray can
happen if the tank is nearly full, and is
more likely in hot weather. Open the
fuel cap slowly and wait for any hiss
noise to stop, then unscrew the cap all
the way.
Turn the fuel cap counterclockwise to
remove. When refueling, hang the fuel cap
from the hook on the fuel door. Fully insert
and latch the fill nozzle, begin fueling.
{Warning
Overfilling the fuel tank by more than
three clicks of a standard fill nozzle may
cause:
.Vehicle performance issues, including
engine stalling and damage to the fuel
system.
.Fuel spills.
.Under certain conditions, fuel fires.Be careful not to spill fuel. Wait five seconds
after you have finished pumping before
removing the fill nozzle. Clean fuel from
painted surfaces as soon as possible. See
Exterior Care
0241. Reinstall the cap by
turning it clockwise until it clicks. Push the
fuel door closed.
{Warning
If a fire starts while you are refueling, do
not remove the fill 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, get the right
type of cap from your dealer. The wrong
type of fuel cap may not fit properly,
may turn on the malfunction indicator
lamp, and could damage the fuel system
and emissions system. See Malfunction
Indicator Lamp (Check Engine Light) 076.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-14583543) -
2021 - crc - 7/10/20
Driving and Operating 175
Refer to the aftermarket electric trailer brake
controller owner's manual to determine wire
color coding of the electric trailer brake
controller. The wire colors on the brake
controller may be different from the vehicle.
Trailer Lamps
Always check all trailer lamps are working at
the beginning of each trip, and periodically
on longer trips.
Turn Signals When Towing a Trailer
When properly connected, the trailer turn
signals will illuminate to indicate the vehicle
is turning, changing lanes, or stopping.
When towing a trailer, the arrows on the
instrument cluster will illuminate even if the
trailer is not properly connected or the bulbs
are burned out.
Tow/Haul Mode
Tow/Haul assists when pulling a heavy
trailer or a large or heavy load. For
instructions on how to enter Tow/Haul
mode, seeTow/Haul Mode 0145.
Tow/Haul Mode is designed to be most
effective when the vehicle and trailer
combined weight is at least 75% of the vehicle's Gross Combined Weight Rating
(GCWR). See
“Trailer Weight” underTrailer
Towing 0164.
Tow/Haul Mode is most useful when towing
a heavy trailer or carrying a large or
heavy load:
.through rolling terrain
.in stop-and-go traffic
.in busy parking lots
Operating the vehicle in Tow/Haul Mode
when lightly loaded or not towing will not
cause damage; however, it is not
recommended and may result in unpleasant
engine and transmission driving
characteristics and reduced fuel economy.
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 TSC is enabled, the Traction Control
System (TCS)/StabiliTrak/ESC warning light
will flash on the instrument cluster. Reduce
vehicle 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
0 147.
{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,
(Continued)

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-14583543) -
2021 - crc - 7/10/20
176 Driving and Operating
Warning (Continued)
unrestrained cargo, improper trailer hitch
configuration, or improperly inflated or
incorrect vehicle or trailer tires. See
Towing Equipment0172 for trailer
ratings and hitch setup recommendations.
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
blow-outs.
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 blow-outs. 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).
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) 076.
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 (Continued)
Warning (Continued)
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 044 and
Adding Equipment to the Airbag-Equipped
Vehicle 045.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-14583543) -
2021 - crc - 7/10/20
Vehicle Care 187
How to Check Automatic Transmission
Fluid
Because this operation can be difficult, it is
recommended to have this check done at
your dealer, which can monitor the
transmission temperature. The transmission
fluid level increases with temperature. To
obtain a highly accurate fluid level check,
the transmission temperature must be
measured.
If it is decided to check the fluid level, be
sure to follow all the instructions here, or a
false reading on the dipstick may occur.
Caution
Too much or too little fluid can damage
the transmission. Too much can mean
that some of the fluid could come out
and fall on hot engine parts or exhaust
system parts, starting a fire. Too little
fluid could cause the transmission to
overheat. Be sure to get an accurate
reading if checking the transmission fluid.
Wait at least 30 minutes with the engine
off, before checking the transmission fluid
level if the vehicle has been driven:
.In hot weather, when outside
temperatures are above 32 °C (90 °F).
.The vehicle is heavily loaded.
.At high speed for quite a while in hot
weather.
.In heavy traffic and hot weather.
.While pulling a trailer.
After driving under these conditions, a hot
check can be performed. The fluid should be
hot, which is 71 °C to 93 °C (160 °F to
200 °F).
A cold fluid level check can be performed
after the vehicle has been sitting for eight
hours or more with the engine off, but this
is used only as a reference. Let the engine
run at idle for five minutes if the outside
temperature is between 15 °C to 32 °C (60 °F
to 90 °F). Should the fluid level be low
during this cold check, the fluid must be
checked warm or hot before adding fluid.
If the outside temperature is colder than 15 °
C (60 °F) or hotter than 32 °C (90 °F), a cold
check cannot be performed.
A warm fluid level check can be performed
by driving the vehicle under lightly loaded
conditions and outside temperatures
between 10 °C to 27 °C (50 °F to 80 °F). The
vehicle should be driven for at least 24 km (15 mi) before performing a warm check.
Checking the fluid warm or hot will give a
more accurate reading of the fluid level than
a cold check.
Because the vehicle is equipped with a
high-efficiency air-to-oil cooler, the
transmission fluid temperature may not
reach the required hot fluid level checking
temperature under normal lightly loaded
driving vehicle conditions.
Checking the Fluid Level
Prepare the vehicle:
1. Park the vehicle on a level place. Keep the engine running.
2. With the parking brake applied, place the shift lever in P (Park).
3. With a foot on the brake pedal, move the shift lever through each gear range,
pausing for about three seconds in each
range. When M is reached, move the
selector from M1 through M3. Then,
position the shift lever in P (Park).
4. Let the engine run at idle for two minutes or more.
Then, without shutting off the engine, use
the steps that follow.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-14583543) -
2021 - crc - 7/10/20
198 Vehicle Care
.Normal brake lining wear. When new
linings are installed, the fluid level goes
back up.
.A fluid leak in the brake hydraulic system.
Have the brake hydraulic system fixed.
With a leak, the brakes will not
work well.
Always clean the brake fluid reservoir cap
and the area around the cap before
removing it.
Do not top off the brake fluid. Adding fluid
does not correct a leak. If fluid is added
when the linings are worn, there will be too
much fluid when new brake linings are
installed. Add or remove fluid, as necessary,
only when work is done on the brake
hydraulic system.
{Warning
If too much brake fluid is added, it can
spill on the engine and burn, if the
engine is hot enough. You or others could
be burned, and the vehicle could be
damaged. Add brake fluid only when
work is done on the brake hydraulic
system. When the brake fluid falls to a low level,
the brake warning light comes on. See
Brake
System Warning Light 077.
Brake fluid absorbs water over time. Replace
brake fluid at the specified intervals to
prevent increased stopping distance. See
Maintenance Schedule 0249.
Checking Brake Fluid
Check brake fluid by looking at the brake
fluid reservoir. See Engine Compartment
Overview 0180.
The fluid level should be above MIN. If it is
not, have the brake hydraulic system
checked to see if there is a leak. After work is done on the brake hydraulic
system, make sure the level is above MIN
but not over the MAX mark.
What to Add
Use only GM approved DOT 3 brake fluid
from a clean, sealed container. See
Recommended Fluids and Lubricants
0255.
{Warning
The wrong or contaminated brake fluid
could result in damage to the brake
system. This could result in the loss of
braking leading to a possible injury.
Always use the proper GM approved
brake fluid.
Caution
If brake fluid is spilled on the vehicle's
painted surfaces, the paint finish can be
damaged. Immediately wash off any
painted surface.
Battery - North America
The original equipment battery is
maintenance free. Do not remove the cap
and do not add fluid.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-14583543) -
2021 - crc - 7/10/20
Vehicle Care 237
To avoid the possibility of the vehicles
rolling, set the parking brake firmly on
both vehicles involved in the jump start
procedure. Put an automatic transmission
in P (Park) or a manual transmission in
Neutral before setting the parking brake.
Caution
If any accessories are left on or plugged
in during the jump starting procedure,
they could be damaged. The repairs
would not be covered by the vehicle
warranty. Whenever possible, turn off or
unplug all accessories on either vehicle
when jump starting.
3. Turn the ignition off on both vehicles. Unplug unnecessary accessories plugged
into the cigarette lighter or the accessory
power outlet. Turn off the radio and all
lamps that are not needed. This will
avoid sparks and help save both
batteries. And it could save the radio!
4. Open the hoods and locate the positive (+) and negative (−) terminal
locations of the other vehicle.
On your van, use the unpainted radio
antenna bracket as a remote negative (−)
terminal.
{Warning
Using a match near a battery can cause
battery gas to explode. People have been
hurt doing this, and some have been
blinded. Use a flashlight if you need
more light.
Battery fluid contains acid that can burn
you. Do not get it on you. If you
accidentally get it in your eyes or on
your skin, flush the place with water and
get medical help immediately.
{Warning
Fans or other moving engine parts can
injure you badly. Keep your hands away
from moving parts once the engine is
running.
5. Check that the jumper cables do not have loose or missing insulation. If they
do, you could get a shock. The vehicles
could be damaged too.
Before you connect the cables, here are
some basic things you should know.
Positive (+) will go to positive (+) or to a
remote positive (+) terminal if the vehicle has one. Negative (−) will go to an
unpainted metal part or to a remote
negative (−) terminal if the vehicle has
one. On your van, use the unpainted
radio antenna bracket as a remote
negative (−) terminal.
Do not connect positive (+) to
negative (−) or you will get a short that
would damage the battery and maybe
other parts too. And do not connect the
negative (−) cable to the negative (−)
terminal on the dead battery because
this can cause sparks.
6. Connect the red positive (+) cable to the
positive (+) terminal of the dead battery.
Use a remote positive (+) terminal if the
vehicle has one. Do not let the other end

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-14583543) -
2021 - crc - 7/10/20
Service and Maintenance 253
(7)Replace air conditioning desiccant every
seven years.
Special Application Services
.Vehicles with Dual Wheels: Check dual
wheel nut torque at 160, 1 600, and
10 000 km (100, 1,000, and 6,000 mi) of
driving. Repeat this service whenever a
tire/wheel is serviced or removed.
.Severe Commercial Use Vehicles Only:
Lubricate chassis components every oil
change.
.Have underbody flushing service
performed. See “Underbody Maintenance”
in Exterior Care 0241.
Additional Maintenance
and Care
Your vehicle is an important investment and
caring for it properly may help to avoid
future costly repairs. To maintain vehicle
performance, additional maintenance
services may be required.
It is recommended that your dealer perform
these services —their trained dealer
technicians know your vehicle best. Your
dealer can also perform a thorough assessment with a multi-point inspection to
recommend when your vehicle may need
attention.
The following list is intended to explain the
services and conditions to look for that may
indicate services are required.
Battery
The 12-volt battery supplies power to start
the engine and operate any additional
electrical accessories.
.To avoid break-down or failure to start
the vehicle, maintain a battery with full
cranking power.
.Trained dealer technicians have the
diagnostic equipment to test the battery
and ensure that the connections and
cables are corrosion-free.
Belts
.Belts may need replacing if they squeak
or show signs of cracking or splitting.
.Trained dealer technicians have access to
tools and equipment to inspect the belts
and recommend adjustment or
replacement when necessary.
Brakes
Brakes stop the vehicle and are crucial to
safe driving.
.Signs of brake wear may include chirping,
grinding, or squealing noises, or difficulty
stopping.
.Trained dealer technicians have access to
tools and equipment to inspect the brakes
and recommend quality parts engineered
for the vehicle.
Fluids
Proper fluid levels and approved fluids
protect the vehicle’s systems and
components. See Recommended Fluids and
Lubricants 0255 for GM approved fluids.
.Engine oil and windshield washer fluid
levels should be checked at every fuel fill.
.Instrument cluster lights may come on to
indicate that fluids may be low and need
to be filled.
Hoses
Hoses transport fluids and should be
regularly inspected to ensure that there are
no cracks or leaks. With a multi-point
inspection, your dealer can inspect the hoses
and advise if replacement is needed.
Lamps
Properly working headlamps, taillamps, and
brake lamps are important to see and be
seen on the road.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-14583543) -
2021 - crc - 7/10/20
Index 281
IndexA
Accessories and Modifications . . . . . . . . . . . .178
Accessory Power . . . . . . . . . . . . . . . . . . . . . . . . . .138
Add-On Electrical Equipment . . . . . . . . . . . . . 176
Additional InformationOnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 274
Additional Maintenance and Care . . . . . . . . 253
Agreements Trademarks and License . . . . . . . . . . . . . . . . 117
Air Cleaner/Filter, Engine . . . . . . . . . . . . . . . . 189
Air Conditioning . . . . . . . . . . . . . . . . . . . . . 119, 122
Air Vents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
Airbag System Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
How Does an Airbag Restrain? . . . . . . . . . . 41
What Makes an Airbag Inflate? . . . . . . . . . 40
What Will You See after an Airbag
Inflates? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
When Should an Airbag Inflate? . . . . . . . . 40
Where Are the Airbags? . . . . . . . . . . . . . . . . 38
Airbags Adding Equipment to the Vehicle . . . . . . . 45
Light On-Off . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
On-Off Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
On-Off Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Readiness Light . . . . . . . . . . . . . . . . . . . . . . . . . 74
Servicing Airbag-Equipped Vehicles . . . . . . 44
System Check . . . . . . . . . . . . . . . . . . . . . . . . . . . 36 Alarm
Vehicle Security . . . . . . . . . . . . . . . . . . . . . . . . . 15
Alert Side Blind Zone (SBZA) . . . . . . . . . . . . . . . . . 155
All-Season Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . 211
AM-FM Radio . . . . . . . . . . . . . . . . . . . . . . . . . . . . .101
Antenna Fixed Mast . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
Multi-band . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
Antilock Brake System (ABS) . . . . . . . . . . . . . .145 Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . . 78
Appearance Care Exterior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 241
Interior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 245
Ashtrays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Assistance Program, Roadside . . . . . . . . . . . . 265
Audio Theft-Deterrent Feature . . . . . . . . . . . . . . . . . 97
Audio Players CD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
Automatic
Door Locks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Headlamp System . . . . . . . . . . . . . . . . . . . . . . 91
Transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . 142
Transmission Fluid . . . . . . . . . . . . . . . . 186, 189
Automatic Transmission Manual Mode . . . . . . . . . . . . . . . . . . . . . . . . . 144
Shift Lock Control Function Check . . . . . . 201