ECU GMC SAVANA 2020 Service Manual

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-13882574) -
2020 - CRC - 11/1/19
234 Vehicle Care
mixture through the filler neck
until the level reaches the base
of the filler neck.
8. Replace the pressure cap. At any time during this procedure
if coolant begins to flow out of
the filler neck, reinstall the
pressure cap.
Caution
If the pressure cap is not tightly
installed, coolant loss and engine
damage may occur. Be sure the
cap is properly and tightly
secured.
Engine Overheating
If the vehicle has a diesel engine,
see the Duramax diesel
supplement.
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.
The vehicle has an indicator to warn
of engine overheating.
There is an engine coolant
temperature gauge on the vehicle's
instrument cluster. See Engine
Coolant Temperature Gauge 089.
If the decision is made not to lift the
hood when this warning appears,
but instead get service help right
away, see Roadside Assistance
Program 0324.
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 fans are 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.
See if the engine cooling fan speed
increases when idle speed is
doubled by pushing the accelerator
pedal down. If it does not, the
vehicle needs service. Turn off the
engine.
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 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.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-13882574) -
2020 - CRC - 11/1/19
Vehicle Care 243
.To check the P (Park)
mechanism's holding ability:
With the engine running, shift to
P (Park). Then release the
parking brake followed by the
regular brake.
Contact your dealer if service is
required.
Wiper Blade Replacement
Windshield wiper blades should be
inspected for wear and cracking.
See Maintenance Schedule 0304.
Replacement blades come in
different types and are removed in
different ways. For proper type and
length, see Maintenance
Replacement Parts 0314.
Caution
Allowing the wiper arm to touch
the windshield when no wiper
blade is installed could damage
the windshield. Any damage that
occurs would not be covered by
(Continued)
Caution (Continued)
the vehicle warranty. Do not allow
the wiper arm to touch the
windshield.
1. Lift the wiper arm away from the windshield.
2. Push the release lever (2) todisengage the hook and push
the wiper arm (1) out of the
blade assembly (3).
3. Push the new blade assembly securely on the wiper arm until
the release lever clicks into
place.
Windshield Replacement
Driver Assistance Systems
If the windshield needs to be
replaced and the vehicle is
equipped with a front camera sensor
for the Driver Assistance Systems, a
GM replacement windshield is
recommended. The replacement
windshield must be installed
according to GM specifications for
proper alignment. If it is not, these
systems may not work properly, they
may display messages, or they may
not work at all. See your dealer for
proper windshield replacement.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-13882574) -
2020 - CRC - 11/1/19
Vehicle Care 247
License Plate Lamp
1. Bulb Socket
2. License Plate BulbAssembly
3. Screws
To replace one of these bulbs:
1. Remove the screws (3) that secure the license plate bulb
assembly (2).
2. Turn the bulb socket (1) counterclockwise and pull the
bulb straight out of the socket.
3. Install the new bulb.
4. Reverse Steps 1 and 2 to reinstall the license plate bulb
assembly.Electrical System
Electrical System
Overload
The vehicle has fuses and circuit
breakers to protect against an
electrical system overload.
When the current electrical load 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.
Fuses and circuit breakers protect
power devices in the vehicle.
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.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-13882574) -
2020 - CRC - 11/1/19
268 Vehicle Care
If the full-size spare tire is part of
the tire rotation, make sure the
tire rotated into the spare
position is stored securely.
Push, pull, and then try to rotate
or turn the tire. If it moves, use
the wheel wrench/hoist shaft to
tighten the cable. SeeTire
Changing 0276.
Use this rotation pattern when
rotating the tires if the vehicle
has single rear wheels.
Use this rotation pattern when
rotating the tires if the vehicle
has dual rear wheels.
When installing dual wheels,
check that the vent holes in the
inner and outer wheels on each
side are lined up.
Adjust the front and rear tires to
the recommended inflation
pressure on the Tire and
Loading Information label after
the tires have been rotated. See
Tire Pressure 0262 and
Vehicle Load Limits 0157. Reset the Tire Pressure Monitor
System. See
Tire Pressure
Monitor Operation 0264.
Check that all wheel nuts are
properly tightened. See “Wheel
Nut Torque” underCapacities
and Specifications 0317.
{Warning
Rust or dirt on a wheel, or on
the parts to which it is
fastened, can make wheel
nuts become loose after time.
The wheel could come off and
cause a crash. When
changing a wheel, remove any
rust or dirt from places where
the wheel attaches to the
vehicle. In an emergency, a
cloth or a paper towel can be
used; however, use a scraper
or wire brush later to remove
all rust or dirt.

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Vehicle Care 275
Caution (Continued)
of the rear axle. Do not use
chains on the tires of the front
axle. Tighten them as tightly as
possible with the ends securely
fastened. Drive slowly and follow
the chain manufacturer's
instructions. If the chains contact
the vehicle, stop and retighten
them. If the contact continues,
slow down until it stops. Driving
too fast or spinning the wheels
with chains on will damage the
vehicle.
For Cutaway models with LT245/
75R16 or LT225/75R16 size single
or dual rear tires, use Low Profile
Z-Chain or SAE Class S cables.
For Cargo or Passenger models
with LT225/75R16 or LT245/75R16
size tires, use Low Profile Z-Chain
cables. SAE Class S chains are not
recommended. If the vehicle has dual rear tires, do
not use individual tire chains. Use
tire chains that fit across both dual
tires.
If a Tire Goes Flat
It is unusual for a tire to blow out
while driving, especially if the tires
are maintained properly. See
Tires
0 254. If air goes out of a tire, it is
much more likely to leak out slowly.
But if there ever is a blowout, here
are a few tips about what to expect
and what to do:
If a front tire fails, the flat tire
creates a drag that pulls the vehicle
toward that side. Take your foot off
the accelerator pedal and grip the
steering wheel firmly. Steer to
maintain lane position, and then
gently brake to a stop, well off the
road, if possible.
A rear blowout, particularly on a
curve, acts much like a skid and
may require the same correction as
used in a skid. Stop pressing the
accelerator pedal and steer to
straighten the vehicle. It may be very bumpy and noisy. Gently brake
to a stop, well off the road,
if possible.
{Warning
Driving on a flat tire will cause
permanent damage to the tire.
Re-inflating a tire after it has been
driven on while severely
underinflated or flat may cause a
blowout and a serious crash.
Never attempt to re-inflate a tire
that has been driven on while
severely underinflated or flat.
Have your dealer or an authorized
tire service center repair or
replace the flat tire as soon as
possible.
{Warning
Lifting a vehicle and getting under
it to do maintenance or repairs is
dangerous without the
appropriate safety equipment and
(Continued)

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-13882574) -
2020 - CRC - 11/1/19
Vehicle Care 277
Remove the retaining wing bolt and
lift it off of the mounting bracket.
Equipment needed for a
15-passenger seating arrangement
is secured on the rear floor on the
passenger side of the vehicle.Remove the retaining wing bolt and
lift it out of the mounting bracket to
access the equipment.The tools you will be using include:
1. Jack
2. Hoist Handle
3. Extension(s)
4. Wheel Wrench
5. Jack Handle
The spare tire is mounted in the rear
underbody of the vehicle.
Use the hoist handle, extension(s),
and the wheel wrench to remove the
underbody-mounted spare tire.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-13882574) -
2020 - CRC - 11/1/19
Vehicle Care 283
Warning (Continued)
to the proper torque specification
after replacing. Follow the torque
specification supplied by the
aftermarket manufacturer when
using accessory locking wheel
nuts. SeeCapacities and
Specifications 0317 for original
equipment wheel nut torque
specifications.
Caution
Improperly tightened wheel nuts
can lead to brake pulsation and
rotor damage. To avoid expensive
brake repairs, evenly tighten the
wheel nuts in the proper
sequence and to the proper
torque specification. See
Capacities and Specifications
0 317 for the wheel nut torque
specification.
11. Use the wheel wrench to tighten the nuts firmly. Turn the
wheel wrench clockwise and in
a crisscross sequence, as
shown.
12. Put the wheel cover or the center cap and plastic wheel
nut caps back on. Remove any
wheel blocks.
Have a technician check the
wheel nut tightness of all
wheels with a torque wrench
after the first 160 km (100 mi)
and then 1 600 km (1,000 mi)
after that. Repeat this service
whenever a tire is removed or serviced. See
Capacities and
Specifications 0317 for more
information.
Storing a Flat or Spare Tire
and Tools
{Warning
Storing a jack, a tire, or other
equipment in the passenger
compartment of the vehicle could
cause injury. In a sudden stop or
collision, loose equipment could
strike someone. Store all these in
the proper place.
{Warning
Failure to follow these tire storage
instructions carefully could result
in personal injury or property
damage if the hoist cable fails or
if the tire comes loose. Make sure
the tire is stored securely before
driving.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-13882574) -
2020 - CRC - 11/1/19
Vehicle Care 285
Caution (Continued)
and could damage the system.
Use only the tools supplied with
the hoist mechanism.
5. Insert the chisel end of the hoist handle, on an angle,
through the hole in the rear
floor panel above the bumper
and onto the hoist shaft.
Do not use the chiseled end of
the wheel wrench.
6. Raise the tire part way upward. Make sure the retainer is
seated in the wheel opening.
7. Raise the tire fully against the underside of the vehicle by
turning the wheel wrench
clockwise until you hear two
clicks or feel it skip twice. You
cannot overtighten the cable.
8. Make sure the tire is storedsecurely. Push, pull (1), and
then try to turn (2) the tire.
If the tire moves, use the wheel
wrench to tighten the cable.
Two clicks mean the tire is up
all the way.
Repeat this tightness check
procedure when checking the
spare tire pressure according
to the scheduled maintenance
information or any time the
spare tire is handled due to
service of other components.Correctly Stored
Incorrectly Stored

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-13882574) -
2020 - CRC - 11/1/19
286 Vehicle Care
9. Return the jacking equipmentto the proper location. Secure
the items and replace the jack
cover.
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 Pressure0262
and
Vehicle Load Limits 0157. For
instructions on how to remove,
install, or store a spare tire, see Tire
Changing 0276.
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 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
different sizes, because they will not
fit. Keep the spare tire and its wheel
together.
If this vehicle has a spare tire that
does not match the original road
tires and wheels in size and type,
do not include the spare in the tire
rotation.
If equipped with a temporary use
full-size spare tire, it is indicated on
the tire sidewall. See
Tire Sidewall
Labeling 0256. The 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.
Jump Starting
Jump Starting - North
America
For more information about the
vehicle battery, see Battery - North
America 0239.
If the vehicle battery has run down,
you may want to use another
vehicle and some jumper cables to
start your vehicle. Be sure to use
the following steps to do it safely.
{Warning
WARNING: Battery posts,
terminals, and related
accessories contain lead and lead
compounds, chemicals known to
the State of California to cause
cancer and birth defects or other
reproductive harm. Batteries also
contain other chemicals known to
the State of California to cause
cancer. WASH HANDS AFTER
(Continued)

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-13882574) -
2020 - CRC - 11/1/19
290 Vehicle Care
Caution (Continued)
vehicle. The repairs would not be
covered by the vehicle warranty.
Always connect and remove the
jumper cables in the correct order,
making sure that the cables do
not touch each other or other
metal.
Jumper Cable Removal
Reverse the sequence exactly when
removing the jumper cables.
After starting the disabled vehicle
and removing the jumper cables,
allow it to idle for several minutes.
Towing the Vehicle
Caution
Incorrectly towing a disabled
vehicle may cause damage. The
damage would not be covered by
the vehicle warranty. Do not lash
or hook to suspension
components. Use the proper
straps around the tires to secure
the vehicle. Do not drag a locked
wheel/tire. Use tire skates or
dollies under any locked wheel/
tire while loading the vehicle. Do
not use a sling type lift to tow the
vehicle. This could damage the
vehicle.
Caution
Improper use of the tow eye can
damage the vehicle. If equipped,
use the tow eye to load a
disabled vehicle onto a flatbed (Continued)
Caution (Continued)
tow truck from a flat road surface,
or to move the vehicle a short
distance. Use caution and low
speeds. The transmission must
be in (N) Neutral when moving
the vehicle.
GM recommends a flatbed tow truck
to transport a disabled vehicle. Use
ramps to help reduce approach
angles, if necessary. A towed
vehicle should have its drive wheels
off the ground. Contact Roadside
Assistance or a professional towing
service if the disabled vehicle must
be towed.