ignition GMC SAVANA 2018 Workshop Manual

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
178 Driving and Operating
Shifting out of Park
The vehicle has an automatic
transmission shift lock control
system. You have to fully apply the
brakes before you can shift from
P (Park) when the ignition is in ON/
RUN or ACC/ACCESSORY. See
Automatic Transmission0180.
The shift lock control system is
designed to:
. Prevent the ignition key from
being removed unless the shift
lever is in P (Park).
. Prevent movement of the shift
lever out of P (Park), unless the
ignition is in ON/RUN or ACC/
ACCESSORY and the regular
brake pedal is applied.
The shift lock control system is
always functional except in the case
of a dead battery or low voltage
(less than 9 V) battery.
If the vehicle has an uncharged
battery or a battery with low voltage,
try charging or jump starting the
battery. See Jump Starting - North
America 0284. To shift out of P (Park):
1. Apply the brake pedal.
2. Turn the ignition to ACC/ ACCESSORY or ON/RUN.
3. Move the shift lever to the desired position.
If you still are unable to shift out of
P (Park): 1. Ease the pressure on the shift lever.
2. While holding down the brake pedal, push the shift lever all
the way into P (Park).
3. Move the shift lever to the desired position.
If you are still having a problem
shifting, have the vehicle serviced.
Parking over Things
That Burn
{Warning
Things that can burn could touch
hot exhaust parts under the
vehicle and ignite. Do not park
over papers, leaves, dry grass,
or other things that can burn.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
182 Driving and Operating
transmission constantly makes
adjustments to improve vehicle
performance according to how the
vehicle is being used, such as with
a heavy load or when the
temperature changes. During this
adaptive shift control process,
shifting might feel different as the
transmission determines the best
settings.
The shift quality of a new vehicle
may not be ideal because the
adaptive shift control process may
not have determined the best
settings for a particular shift or
condition. Shift quality will improve
with continued driving.
When temperatures are very cold,
the transmission's gear shifting
could be delayed, providing more
stable shifts until the engine warms
up. Shifts could be more noticeable
with a cold transmission. This
difference in shifting is normal.
M :This position lets drivers select
the range of gears appropriate for
current driving conditions. If the vehicle has this feature, see
“Range
Selection Mode” underManual
Mode 0183.
1 : This position reduces vehicle
speed without using the brakes.
You can use it for major/severe
downgrades where the vehicle
would otherwise accelerate due to
steepness of grade. When you shift
to 1 (First) it provides the lowest
gear appropriate to current road
speed and continues to downshift
as the vehicle slows, eventually
downshifting to 1 (First) gear. The
transmission can be held in 1 (First)
gear using Range Selection Mode
or the shift lever. See “Range
Selection Mode” underManual
Mode 0183.
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
(Continued)
Caution (Continued)
is stuck, do not spin the tires.
When stopping on a hill, use the
brakes to hold the vehicle in
place.
Normal Mode Grade Braking
This mode is enabled when the
vehicle is started, but is not enabled
in Range Selection Mode. It assists
in maintaining desired vehicle
speeds when driving on downhill
grades by using the engine and
transmission to slow the vehicle.
The first time the system activates
for each ignition key cycle.
To disable or enable Normal Mode
Grade Braking within the current
ignition key cycle, press and hold
the Tow/Haul button for
three seconds.
For other forms of grade braking,
seeTow/Haul Mode 0184 and
Cruise Control 0189.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
184 Driving and Operating
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 0106.
Also see “Tow/Haul Mode” under
Towing Equipment 0207.
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 Mode0183.
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 0207.
For other forms of grade braking,
see Automatic Transmission 0180
and Cruise Control 0189.
Brakes
Antilock Brake
System (ABS)
This vehicle has an Antilock Brake
System (ABS), an advanced
electronic braking system that helps
prevent a braking skid.
When the vehicle begins to drive
away, ABS checks itself.
A momentary motor or clicking noise
may be heard while this test is going
on, and it may even be noticed that
the brake pedal moves a little. This
is normal.
If there is a problem with ABS, this
warning light stays on. See Antilock
Brake System (ABS) Warning Light
0 106.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
Driving and Operating 185
If driving safely on a wet road and it
becomes necessary to slam on the
brakes and continue braking to
avoid a sudden obstacle, a
computer senses the wheels are
slowing down. If one of the wheels
is about to stop rolling, the computer
will separately work the brakes at
each wheel.
ABS can change the brake pressure
to each wheel, as required, faster
than any driver could. This can help
you steer around the obstacle while
braking hard.
As the brakes are applied, the
computer keeps receiving updates
on wheel speed and controls
braking pressure accordingly.
Remember: ABS does not change
the time needed to get a foot up to
the brake pedal or always decrease
stopping distance. If you get too
close to the vehicle in front of you,
there will not be enough time to
apply the brakes if that vehicle
suddenly slows or stops. Always
leave enough room up ahead to
stop, even with ABS.Using ABS
Do not pump the brakes. Just hold
the brake pedal down firmly and let
ABS work. You may hear the ABS
pump or motor operating and feel
the brake pedal pulsate. This is
normal.
Braking in Emergencies
ABS allows you to steer and brake
at the same time. In many
emergencies, steering can help
more than even the very best
braking.
Parking Brake
To set the parking brake, hold the
regular brake pedal, then push
down the parking brake pedal.
If the ignition is on, the brake
system warning light will come on.
To release the parking brake, hold
the regular brake pedal down. Pull
the handle, located just above the
parking brake pedal, with the
parking brake symbol, to release the
parking brake.
If the ignition is on when the parking
brake is released, the brake system
warning light will go off.
Caution
Driving with the parking brake on
can overheat the brake system
and cause premature wear or
damage to brake system parts.
Make sure that the parking brake
is fully released and the brake
warning light is off before driving.

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
Vehicle Care 211
Vehicle Care
General Information
General Information . . . . . . . . . . 212
California Proposition65 Warning . . . . . . . . . . . . . . . . . 212
California Perchlorate Materials Requirements . . . . . 213
Accessories and Modifications . . . . . . . . . . . . . . . . 213
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 213
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 214
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 215
Engine Oil . . . . . . . . . . . . . . . . . . . . 218
Engine Oil Life System . . . . . . . 220
Automatic Transmission Fluid (6-Speed Transmission) . . . . . 221
Automatic Transmission Fluid (8-Speed Transmission) . . . . . 224
Engine Air Cleaner/Filter . . . . . . 225
Cooling System . . . . . . . . . . . . . . 226
Engine Overheating . . . . . . . . . . 231
Engine Fan . . . . . . . . . . . . . . . . . . . 232
Power Steering Fluid . . . . . . . . . 233
Washer Fluid . . . . . . . . . . . . . . . . . 233 Brakes . . . . . . . . . . . . . . . . . . . . . . . 234
Brake Fluid . . . . . . . . . . . . . . . . . . . 235
Battery - North America . . . . . . 236
Rear Axle . . . . . . . . . . . . . . . . . . . . 237
Noise Control System . . . . . . . . 238
Starter Switch Check . . . . . . . . . 239
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 239
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . . . 240
Park Brake and P (Park) Mechanism Check . . . . . . . . . . 240
Wiper Blade Replacement . . . . 240
Windshield Replacement . . . . . 241
Gas Strut(s) . . . . . . . . . . . . . . . . . . 241
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . . . 242
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 243
Halogen Bulbs . . . . . . . . . . . . . . . . 243
Front Turn Signal, Sidemarker, and Parking Lamps . . . . . . . . . 243
Taillamps . . . . . . . . . . . . . . . . . . . . . 243
Center High-Mounted Stoplamp (CHMSL) . . . . . . . . . 245
License Plate Lamp . . . . . . . . . . 245
Electrical System
Electrical System Overload . . . 246
Fuses and Circuit Breakers . . . 246
Engine Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . 247
Floor Console Fuse Block . . . . 251
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 253
All-Season Tires . . . . . . . . . . . . . . 253
Winter Tires . . . . . . . . . . . . . . . . . . 254
All-Terrain Tires . . . . . . . . . . . . . . . 254
Tire Sidewall Labeling . . . . . . . . 254
Tire Designations . . . . . . . . . . . . . 257
Tire Terminology and
Definitions . . . . . . . . . . . . . . . . . . 258
Tire Pressure . . . . . . . . . . . . . . . . . 261
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . . . . 262
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . 263
Tire Inspection . . . . . . . . . . . . . . . . 266
Tire Rotation . . . . . . . . . . . . . . . . . 266
Dual Tire Rotation . . . . . . . . . . . . 268
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . 268
Buying New Tires . . . . . . . . . . . . . 269
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . . 271

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
240 Vehicle Care
1. Before starting this check, besure there is enough room
around the vehicle. It should be
parked on a level surface.
2. Apply the parking brake. Be ready to apply the regular
brake immediately if the vehicle
begins to move.
3. With the engine off, turn the ignition on, but do not start the
engine. Without applying the
regular brake, try to move the
shift lever out of P (Park) with
normal effort. If the shift lever
moves out of P (Park), contact
your dealer for service.
Ignition Transmission
Lock Check
While parked, and with the parking
brake set, try to turn the ignition off
in each shift lever position.
.The ignition should turn to off
only when the shift lever is in
P (Park).
. The ignition key should come
out only when the ignition is off. Contact your dealer if service is
required.
Park Brake and P (Park)
Mechanism Check
{Warning
When you are doing this check,
the vehicle could begin to move.
You or others could be injured
and property could be damaged.
Make sure there is room in front
of the vehicle in case it begins to
roll. Be ready to apply the regular
brake at once should the vehicle
begin to move.
Park on a fairly steep hill, with the
vehicle facing downhill. Keeping
your foot on the regular brake, set
the parking brake.
. To check the parking brake's
holding ability: With the engine
running and the transmission in
N (Neutral), slowly remove foot pressure from the regular brake
pedal. Do this until the vehicle is
held by the parking brake only.
. 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 0301.
Replacement blades come in
different types and are removed in
different ways. For proper type and
length, see Maintenance
Replacement Parts 0310.

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
248 Vehicle Care
FusesUsage
3 Right trailer stoplamp/Turnlamp
4 –
5 –
6 Fuel system control module/Ignition
7 Body control module 5
8 Body control module 7
9 Body control module 4
10 Instrument cluster
11 Trailer wiring
12 –
13 Interior rear vision camera module
14 Windshield washer Fuses
Usage
16 Horn
17 Transmission
18 A/C
19 Engine control module battery
20 Cutaway/Left stoplamp/Turnlamp
21 Left trailer stoplamp/Turnlamp
22 Cutaway/Right stoplamp/Turnlamp
23 –
24 Fuel pump
25 Auxiliary power outlet
26 Body control module 3
27 Special equipment option Fuses
Usage
28 Airbag
29 Steering wheel sensor
30 Engine control module Ignition
31 Transmission control module
Ignition
32 Transmission control module 1
battery/Engine
control module
battery power (gas
6 cyl)
33 Rear parking aid module
34 –
35 –
36 Fuel system control module battery

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
Vehicle Care 249
FusesUsage
41 Transmission control 2 module
battery power
42 Trailer wiring
43 –
44 Starter solenoid
45 Engine control module/Powertrain
46 AC DC inverter
47 Cooling fan –low
51 Left high-beam headlamp
52 Right high-beam headlamp
53 Left low-beam headlamp
54 Right low-beam headlamp Fuses
Usage
55 Wipers
56 Canister vent solenoid
58 Body control module 2
59 Body control module 1
61 Engine oil solenoid
62 O2 sensor 2
63 –
64 Mass air flow/ Canister vent
65 Ignition/Injectors –odd
66 Daytime running lamps 2
67 Daytime running lamps 1 Fuses
Usage
68 Auxiliary stoplamps
69 External power for trailer
70 Upfitter stoplamps
71 Fuel heater/Flex fuel sensor
72 Body control module 6
73 Lighter/Data link connector
74 Front blower
75 V6 fuel injectors
76 –
77 O2 sensor 1
78 Engine control module/Powertrain
79 Ignition/Injectors –even

GMC Savana Owner Manual (GMNA-Localizing-U.S./Canada-11374214) -
2018 - CRC - 2/2/18
252 Vehicle Care
Mini-Fuse UsageF11 –/ OnStar
F12 ECM batt
F13 HVAC 2
F14 HVAC 1
F15 –
F16 Upfitter 1
F17 Exterior rearview heated mirrors
F18 Rear window defogger
F19 Compass
F20 Radio/Chime/ SiriusXM satellite
radio
F21 Remote function actuator/Tire
pressure monitor
F22 Ignition switch/ Discrete logic
ignition sensor
F23 Instrument cluster
F24 – Mini-Fuse Usage
F25 HVAC control
F26 Auxiliary/Trailer reverse lamps
F27 Reverse lamps
F28 Upfitter 2/Reading lamps
F29 Rear blower
F30 Upfitter/Courtesy lamps
F31 Front door lock
F32 Rear door lock
F33 Cargo door unlock
F34 Passenger door unlock
F35 Rear passenger door unlock
F36 Driver door lock
F37 Empty
F38 – Relays Usage
K1 Run
K2 –
K3 Parking lamps
K4 Upfitter 2
K5 Rear defogger
K6 Retained accessory power
Circuit
Breaker Usage
CB1 Power seats
CB2 Power windows