ignition CHEVROLET TAHOE 2018 Repair Manual
[x] Cancel search | Manufacturer: CHEVROLET, Model Year: 2018, Model line: TAHOE, Model: CHEVROLET TAHOE 2018Pages: 443, PDF Size: 6.05 MB
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Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349385) - 2018 - crc - 11/3/17
240 Driving and Operating
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
Set the parking brake by holding the
regular brake pedal down, then
pushing down the parking brake
pedal.
If the ignition is on, the brake
system warning light will come on.
SeeBrake System Warning Light
0 155.
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.
To release the parking brake, hold
the regular brake pedal down, then
push down momentarily on the
parking brake pedal until you feel
the pedal release. Slowly pull your
foot up off the parking brake pedal.
If the parking brake is not released
when you begin to drive, a DIC
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Driving and Operating 245
ride and handling characteristics
when the vehicle is loaded or towing
a trailer. See“Tow/Haul Mode”
under Towing Equipment 0278.
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.
Automatic Level Control
The Automatic Level Control (ALC)
rear suspension is available on
light-duty vehicles and comes as a
part of the Magnetic Ride Control
suspension, if equipped. ALC may
also be available as a stand alone
feature.
This type of level control is fully
automatic and will provide a better
leveled riding position as well as
better handling under a variety of
passenger and loading conditions.
An air compressor connected to the rear shocks will raise or lower the
rear of the vehicle to maintain
proper vehicle height. The system is
activated when the ignition key is
turned on and will automatically
adjust vehicle height thereafter. The
system may exhaust (lower vehicle
height) for up to 10 minutes after the
ignition key has been turned off.
You may hear the air compressor
operating when the height is being
adjusted.
If a weight-distributing hitch is being
used, it is recommended to allow
the shocks to inflate, thereby
leveling the vehicle prior to adjusting
the hitch.
Cruise Control
{Warning
Cruise control can be dangerous
where you cannot drive safely at
a steady speed. Do not use
cruise control on winding roads or
in heavy traffic.
Cruise control can be dangerous
on slippery roads. On such roads,
fast changes in tire traction can
cause excessive wheel slip, and
you could lose control. Do not use
cruise control on slippery roads.
With cruise control, a speed of
about 40 km/h (25 mph) or more can
be maintained without keeping your
foot on the accelerator. Cruise
control does not work at speeds
below about 40 km/h (25 mph).
If the brakes are applied, the cruise
control disengages.
For an explanation of how cruise
control interacts with the Range
Selection Mode, Tow/Haul Mode,
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Driving and Operating 247
Once the vehicle speed reaches
about 40 km/h (25 mph) or more,
briefly press +RES. The vehicle
returns to the previous set speed.
Increasing Speed While Using
Cruise Control
If the cruise control system is
already activated:
.Press and hold +RES on the
steering wheel until the vehicle
accelerates to the desired
speed, then release it.
. To increase vehicle speed in
small increments, briefly press
+RES. For each press, the
vehicle goes about 1.6 km/h
(1 mph) faster.
The speedometer reading can be
displayed in either English or metric
units. See Instrument Cluster 0143.
The increment value used depends
on the units displayed. Reducing Speed While Using
Cruise Control
If the cruise control system is
already activated:
.
Press and hold SET– until the
desired lower speed is reached,
then release it.
. To slow down in small
increments, briefly press SET–.
For each press, the vehicle goes
about 1.6 km/h (1 mph) slower.
The speedometer reading can be
displayed in either English or metric
units. See Instrument Cluster 0143.
The increment value used depends
on the units displayed.
Passing Another Vehicle While
Using Cruise Control
Use the accelerator pedal to
increase the vehicle speed. When
you take your foot off the pedal, the
vehicle will slow down to the
previous set cruise speed. While
pressing the accelerator pedal or
shortly following the release to
override cruise control, briefly pressing SET–
will result in cruise
control set to the current vehicle
speed.
Using Cruise Control on Hills
How well the cruise control works
on hills depends on the vehicle
speed, the load, and the steepness
of the hills. When going up steep
hills, pressing the accelerator pedal
may be necessary to maintain
vehicle speed. When going
downhill, Cruise Grade Braking
helps maintain the driver selected
speed.
Cruise Grade Braking is enabled
when the vehicle is started and
cruise control is active. It is not
enabled in Range Selection Mode.
It assists in maintaining driver
selected speed when driving on
downhill grades by using the engine
and transmission to slow the
vehicle.
To disable and enable Cruise Grade
Braking for the current ignition
cycle, press and hold the Tow/Haul
button for five seconds. A DIC
message displays.
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248 Driving and Operating
For other forms of descent control,
seeHill Descent Control (HDC)
0 244, Automatic Transmission
0 228, and Tow/Haul Mode 0233.
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
5.
Erasing Speed Memory
The cruise control set speed is
erased from memory when
5is
pressed, or if the ignition is
turned off.
Adaptive Cruise Control
If equipped with Adaptive Cruise
Control (ACC), it allows for selecting
the cruise control set speed and
following gap. Read this entire
section before using this system. ACC uses a camera and radar
sensors to detect other vehicles.
See
Radio Frequency Statement
0 414. The following gap is the
following time (or distance) between
your vehicle and a vehicle detected
directly ahead in your path, moving
in the same direction. If no vehicle
is detected in your path, ACC works
like regular cruise control.
If a vehicle is detected in your path,
ACC can speed up the vehicle or
apply limited, moderate braking to
maintain the selected following gap.
To disengage ACC, apply the brake.
If the Traction Control System (TCS)
or electronic stability control system
activates while ACC is engaged,
ACC may automatically disengage.
See Traction Control/Electronic
Stability Control 0242. When road
conditions allow ACC to be safely
used, the ACC can be turned
back on.
ACC will not engage if the TCS or
electronic stability control system is
disabled.
{Warning
ACC has limited braking ability
and may not have time to slow
the vehicle down enough to avoid
a collision with another vehicle
you are following. This can occur
when vehicles suddenly slow or
stop ahead, or enter your lane.
Also see “Alerting the Driver” in
this section. Complete attention is
always required while driving and
you should be ready to take
action and apply the brakes. See
Defensive Driving 0202.
{Warning
ACC will not detect or brake for
children, pedestrians, animals,
or other objects.
Do not use ACC when:
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Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/
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254 Driving and Operating
Other Vehicle Lane Changes
ACC will not detect a vehicle ahead
until it is completely in the lane. The
brakes may need to be manually
applied.
Do Not Use ACC on Hills and
When Towing a Trailer
Do not use ACC when driving on
steep hills or when towing a trailer.
ACC will not detect a vehicle in the
lane while driving on steep hills. The
driver will often need to take over
acceleration and braking on steep
hills, especially when towing a
trailer. If the brakes are applied, the
ACC disengages.
Disengaging ACC
There are three ways to
disengage ACC:
.Step lightly on the brake pedal.
. Press
*.
. Press
5.
Erasing Speed Memory
The cruise control set speed is
erased from memory if
5is pressed
or if the ignition is turned off.
Cleaning the Sensing System
The radar sensor on the front of the
vehicle can become blocked by
snow, ice, dirt, or mud. This area
needs to be cleaned for ACC to
operate properly. For cleaning instructions, see
“Washing the Vehicle”
under
Exterior Care 0378.
System operation may also be
limited under snow, heavy rain,
or road spray conditions.
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Driving and Operating 283
The ITBC system is powered
through the vehicle's electrical
system. Turning the ignition off will
also turn off the ITBC system. The
ITBC system is fully functional only
when the ignition is on.
{Warning
Connecting a trailer that has an
air brake system may result in
reduced or complete loss of trailer
braking. There may be an
increase in stopping distance or
trailer instability which could
result in personal injury or
damage to the vehicle, trailer,
or other property. Use the ITBC
system only with electric or
electric over hydraulic trailer
brakes.Trailer Brake Control Panel
1. Manual Trailer Brake Apply
Lever
2. Trailer Gain Adjustment Buttons
The ITBC system has a control
panel on the instrument panel to the
left of the steering column. The
control panel allows adjustment to
the amount of output, referred to as
Trailer Gain, available to the trailer
brakes and allows manual
application of the trailer brakes. The
Trailer Brake Control Panel is used
along with the Trailer Brake Display Page on the DIC to adjust and
display power output to the trailer
brakes.
Trailer Brake DIC Display Page
The ITBC system displays
messages in the Driver Information
Center (DIC).
The display page indicates Trailer
Gain setting, power output to the
trailer brakes, trailer connection, and
system operational status.
To display the Trailer Brake Display
Page do any of the following:
.
Scroll through the DIC menu
pages.
. Press a Trailer Gain button.
If the Trailer Brake Display Page
is not currently displayed, press
a Trailer Gain button to recall the
current Trailer Gain setting.
Each press and release of the
gain buttons will then change the
Trailer Gain setting.
. Activate the Manual Trailer
Brake apply lever.
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Driving and Operating 285
Adjusting Trailer Gain at
speeds lower than 32 to
40 km/h (20 to 25 mph) may
result in an incorrect gain
setting.
2. Adjust the Trailer Gain, using the Trailer Gain adjustment
buttons, to just below the point
of trailer wheel lock-up,
indicated by trailer wheel
squeal or tire smoke when a
trailer wheel locks.
Trailer wheel lock-up may not
occur if towing a heavily loaded
trailer. In this case, adjust the
Trailer Gain to the highest
allowable setting for the towing
condition.
3. Readjust Trailer Gain any time vehicle loading, trailer loading,
or road surface conditions
change or if trailer wheel
lock-up is noticed at any time
while towing. Other ITBC-Related DIC Messages
In addition to displaying TRAILER
GAIN and OUTPUT through the
DIC, trailer connection and ITBC
system status are displayed on
the DIC.
TRAILER CONNECTED: This
message will briefly display when a
trailer with electric brakes is first
connected to the vehicle. This
message will automatically turn off
in about 10 seconds. This message
can be acknowledged before it
automatically turns off.
CHECK TRAILER WIRING: This
message will display if:
.
The ITBC system first
determines connection to a
trailer with electric brakes and
then the trailer harness becomes
disconnected from the vehicle.
If the disconnect occurs while
the vehicle is stationary, this
message will automatically turn
off in about 30 seconds. This
message will also turn off if it is
acknowledged or if the trailer
harness is reconnected. If the disconnect occurs while
the vehicle is moving, this
message will continue until the
ignition is turned off. This
message will also turn off if it is
acknowledged or if the trailer
harness is reconnected.
. There is an electrical fault in the
wiring to the trailer brakes. This
message will continue as long
as there is an electrical fault in
the trailer wiring. This message
will also turn off if it is
acknowledged.
To determine if the electrical fault is
on the vehicle side or trailer side of
the trailer wiring harness
connection: 1. Disconnect the trailer wiring harness from the vehicle.
2. Turn the ignition off.
3. Wait 10 seconds, then turn the ignition back to RUN.
4. If the CHECK TRAILER WIRING message reappears,
the electrical fault is on the
vehicle side.
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Chevrolet Tahoe/Suburban Owner Manual (GMNA-Localizing-U.S./Canada/
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286 Driving and Operating
If the CHECK TRAILER
WIRING message only
reappears when connecting the
trailer wiring harness to the
vehicle, the electrical fault is on
the trailer side.
SERVICE TRAILER BRAKE
SYSTEM: This message will display
when there is a problem with the
ITBC system. If this message
continues over multiple ignition
cycles, there is a problem with the
ITBC system. Have the vehicle
serviced.
If either the CHECK TRAILER
WIRING or SERVICE TRAILER
BRAKE SYSTEM message displays
while driving, the ITBC system may
not be fully functional or may not
function at all. When traffic
conditions allow, carefully pull the
vehicle over to the side of the road
and turn the ignition off. Check the
wiring connection to the trailer and
turn the ignition back on. If either of
these messages continues, either
the vehicle or trailer needs service. A GM dealer may be able to
diagnose and repair problems with
the trailer. However, any diagnosis
and repair of the trailer is not
covered under the vehicle warranty.
Contact your trailer dealer for
assistance with trailer repairs and
trailer warranty information.
Trailer Sway
Control (TSC)
Vehicles with StabiliTrak have a
Trailer Sway Control (TSC) feature.
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. If the vehicle
is equipped with the Integrated
Trailer Brake Control (ITBC) system,
and the trailer has the electric
actuated brake system, StabiliTrak
may also apply the trailer brakes.
If TSC is enabled, the Traction
Control System (TCS)/StabiliTrak
warning light will flash on theinstrument 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 0242.
{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
safe speed. Check the trailer and
vehicle to help correct possible
causes. These could include an
improperly or overloaded trailer,
unrestrained cargo, improper
trailer hitch configuration,
excessive vehicle-trailer speed,
or improperly inflated or incorrect
vehicle or trailer tires. See Towing
Equipment 0278 for trailer ratings
and hitch setup
recommendations.
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Vehicle Care 289
Vehicle Care
General Information
General Information . . . . . . . . . . 290
California Proposition65 Warning . . . . . . . . . . . . . . . . . 291
California Perchlorate Materials Requirements . . . . . 291
Accessories and Modifications . . . . . . . . . . . . . . . . 291
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 292
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 292
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 293
Engine Oil . . . . . . . . . . . . . . . . . . . . 297
Engine Oil Life System . . . . . . . 299
Automatic Transmission Fluid (6-Speed Transmission) . . . . . 301
Automatic Transmission Fluid (10-Speed Transmission) . . . 304
Engine Air Cleaner/Filter . . . . . . 304
Cooling System . . . . . . . . . . . . . . 305
Engine Overheating . . . . . . . . . . 309
Engine Fan . . . . . . . . . . . . . . . . . . . 310
Power Steering Fluid . . . . . . . . . 311
Washer Fluid . . . . . . . . . . . . . . . . . 311 Brakes . . . . . . . . . . . . . . . . . . . . . . . 312
Brake Fluid . . . . . . . . . . . . . . . . . . . 312
Battery - North America . . . . . . 314
Four-Wheel Drive . . . . . . . . . . . . . 314
Front Axle . . . . . . . . . . . . . . . . . . . . 315
Rear Axle . . . . . . . . . . . . . . . . . . . . 315
Starter Switch Check . . . . . . . . . 316
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 317
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . . . 317
Park Brake and P (Park) Mechanism Check . . . . . . . . . . 317
Wiper Blade Replacement . . . . 318
Glass Replacement . . . . . . . . . . 319
Windshield Replacement . . . . . 319
Gas Strut(s) . . . . . . . . . . . . . . . . . . 319
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . . . 320
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 321
Halogen Bulbs . . . . . . . . . . . . . . . . 321
High Intensity Discharge (HID) Lighting . . . . . . . . . . . . . . . . . . . . . 321
LED Lighting . . . . . . . . . . . . . . . . . 321
Headlamps . . . . . . . . . . . . . . . . . . . 321
Fog Lamps . . . . . . . . . . . . . . . . . . . 322
Front Turn Signal Lamps . . . . . 322 Taillamps, Turn Signal,
Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . . . 322
License Plate Lamp . . . . . . . . . . 324
Electrical System
Electrical System Overload . . . 324
Fuses and Circuit Breakers . . . 325
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 325
Instrument Panel Fuse Block (Left) . . . . . . . . . . . . . . . . . 330
Instrument Panel Fuse Block (Right) . . . . . . . . . . . . . . . . . . . . . . 333
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 335
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 336
All-Season Tires . . . . . . . . . . . . . . 337
Winter Tires . . . . . . . . . . . . . . . . . . 337
Low-Profile Tires . . . . . . . . . . . . . 338
All-Terrain Tires . . . . . . . . . . . . . . . 338
Tire Sidewall Labeling . . . . . . . . 338
Tire Designations . . . . . . . . . . . . . 339
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . . . 340
Tire Pressure . . . . . . . . . . . . . . . . . 343
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . 344
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Vehicle Care 311
system, the fans may change to
high speed and an increase in fan
noise may be heard. This is normal
and indicates that the cooling
system is functioning properly. The
fans will change to low speed when
additional cooling is no longer
required.
The electric engine cooling fans
may run after the engine has been
turned. off. This is normal and no
service is required.
Power Steering Fluid
For a heavy-duty Suburban, see the
Suburban Heavy-Duty Package
supplement.
Washer Fluid
What to Use
When windshield washer fluid needs
to be added, be sure to read the
manufacturer's instructions before
use. Use a fluid that has sufficient
protection against freezing in an
area where the temperature may fall
below freezing.
Adding Washer Fluid
The vehicle has a low washer fluid
message on the DIC that comes on
when the washer fluid is low. The
message is displayed for
15 seconds at the start of each
ignition cycle. When the WASHER
FLUID LOW ADD FLUID message
displays, washer fluid will need to
be added to the windshield washer
fluid reservoir.
Open the cap with the washer
symbol on it. Add washer fluid until
the tank is full. SeeEngine
Compartment Overview 0293 for
reservoir location.
Caution
. Do not use washer fluid that
contains any type of water
repellent coating. This can
cause the wiper blades to
chatter or skip.
. Do not use engine coolant
(antifreeze) in the
windshield washer. It can
damage the windshield
washer system and paint.
. Do not mix water with
ready-to-use washer fluid.
Water can cause the
solution to freeze and
damage the washer fluid
tank and other parts of the
washer system.
. When using concentrated
washer fluid, follow the
manufacturer instructions for
adding water.
. Fill the washer fluid tank
only three-quarters full when
it is very cold. This allows
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