change CHEVROLET TRAILBLAZER 2021 Repair Manual

Chevrolet Trailblazer Owner Manual (GMNA-Localizing-U.S./Canada-
14400528) - 2021 - CRC - 11/7/19
Driving and Operating 215
Selecting the Follow Distance Gap
When a slower moving vehicle is detected
ahead within the selected following gap,
ACC will adjust the vehicle's speed and
attempt to maintain the follow distance gap
selected.
Press
[on the steering wheel to adjust
the following gap. Each press cycles the gap
button through three settings: Far, Medium,
or Near.
When pressed, the current gap setting
displays briefly on the instrument cluster.
The gap setting will be maintained until it is
changed.
Since each gap setting corresponds to a
following time (Far, Medium, or Near), the
following distance will vary based on vehicle
speed. The faster the vehicle speed, the
further back your vehicle will follow a
vehicle detected ahead. Consider traffic and
weather conditions when selecting the
following gap. The range of selectable gaps
may not be appropriate for all drivers and
driving conditions. Changing the gap setting automatically
changes the alert timing sensitivity (Far,
Medium, or Near) for the Forward Collision
Alert (FCA) feature. See
Forward Collision
Alert (FCA) System 0223.
Alerting the Driver
If ACC is engaged, driver action may be
required when ACC cannot apply sufficient
braking because of approaching a vehicle
too rapidly.
When this condition occurs, six red lights
will flash on the windshield and eight beeps
will sound from the front. See “Collision/
Detection Systems” underVehicle
Personalization 0110.
See Defensive Driving 0182.
Approaching and Following a Vehicle
The vehicle ahead indicator is in the
instrument cluster. It only displays when a
vehicle is detected in your vehicle’s path
moving in the same direction. If this symbol
is not displaying, ACC will not respond to or
brake for vehicles ahead.
ACC automatically slows the vehicle down
and adjusts vehicle speed to follow a
detected vehicle ahead at the selected
following gap. The vehicle speed increases or
decreases to follow a detected vehicle in
front of your vehicle when that vehicle is
traveling slower than your vehicle set speed.
It may apply limited braking, if necessary.
When braking is active, the brake lamps will
come on. The automatic braking may feel or
sound different than if the brakes were
applied manually. This is normal.

Chevrolet Trailblazer Owner Manual (GMNA-Localizing-U.S./Canada-
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218 Driving and Operating
ACC may detect a vehicle that is not in your
lane and apply the brakes.
ACC may occasionally provide an alert and/
or braking that is considered unnecessary.
It could respond to vehicles in different
lanes or stationary objects when entering or
exiting a curve. This is normal operation.
The vehicle does not need service.
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.
Objects Not Directly in Front of Your
Vehicle
The detection of objects in front of the
vehicle may not be possible if:
.The vehicle or object ahead is not within
your lane.
.The vehicle ahead is shifted, not centered,
or is shifted to one side of the lane.
Driving in Narrow Lanes
Vehicles in adjacent traffic lanes or roadside
objects may be incorrectly detected when
located along the roadway.
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. If the brakes are applied, ACC
disengages.
Disengaging ACC
There are three ways to disengage ACC:
.Step lightly on the brake pedal.
.Press*.
.Press5.
Erasing Speed Memory
The ACC set speed is erased from memory if
5is pressed or if the ignition is turned off.
Weather Conditions Affecting ACC
If the interior temperature is extremely
high, the instrument cluster may indicate
that ACC is temporarily unavailable. This can
be caused by extreme hot weather
conditions with direct sunlight on the front
camera. ACC will return to normal operation
once the cabin temperature is lower.
Conditions that are associated with low
visibility, such as fog, rain, snow, or road
spray, may limit ACC performance. Water

Chevrolet Trailblazer Owner Manual (GMNA-Localizing-U.S./Canada-
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Driving and Operating 219
droplets from rain or snow that remain on
the windshield may also limit ACC’s ability
to detect objects.
Lighting Conditions Affecting ACC
The ACC front camera can be affected by
poor lighting conditions, and ACC may have
limited performance when:
.There are changes in brightness, such as
entering and exiting tunnels, bridges, and
overpasses.
.Low sun angles cause the camera to not
detect objects, or it is more difficult to
detect objects in the same traffic lane.
.Lighting is poor in the evening or early
morning
.There are multiple changes in brightness
or shadows along the vehicle roadway.
.In a tunnel without the headlamps on,
or in a tunnel when there is a vehicle in
front that does not have its taillamps on.
.Subjected to strong light from opposing
lane traffic in the front of the vehicle,
such as high-beam headlamps from
oncoming traffic.
Accessory Installations and Vehicle
Modifications
Do not install or place any object around
the front camera windshield area that would
obstruct the front camera view.
Do not install objects on top of the vehicle
that overhang and obstruct the front
camera, such as a canoe, kayak, or other
items that can be transported on a roof rack
system. SeeRoof Rack System 080.
Do not modify the hood, headlamps, or fog
lamps, as this may limit the camera’s ability
to detect an object.
Cleaning the Sensing System
The camera sensor on the windshield behind
the rearview mirror can become blocked by
snow, ice, dirt, mud, or debris. This area
needs to be cleaned for ACC to operate
properly.
The vehicle headlamps may need to be
cleaned due to dirt, snow, or ice. Objects
that are not illuminated correctly may be
difficult to detect. If ACC will not operate, regular cruise control
may be available. See
“Switching Between
ACC and Regular Cruise Control” in this
section. Always consider driving conditions
before using either cruise control system.
For cleaning instructions, see “Washing the
Vehicle” underExterior Care 0307.
Driver Assistance Systems
This vehicle may be equipped with driver
assistance systems that operate using radio
frequency. See Radio Frequency Statement
0 340.
This vehicle may have features that work
together to help avoid crashes or reduce
crash damage while driving, backing, and
parking. Read this entire section before
using these systems.
{Warning
Do not rely on the Driver Assistance
Systems. These systems do not replace
the need for paying attention and driving
safely. You may not hear or feel alerts or
warnings provided by these systems.
(Continued)

Chevrolet Trailblazer Owner Manual (GMNA-Localizing-U.S./Canada-
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220 Driving and Operating
Warning (Continued)
Failure to use proper care when driving
may result in injury, death, or vehicle
damage. SeeDefensive Driving 0182.
Under many conditions, these systems
will not:
.Detect children, pedestrians, bicyclists,
or animals.
.Detect vehicles or objects outside the
area monitored by the system.
.Work at all driving speeds.
.Warn you or provide you with enough
time to avoid a crash.
.Work under poor visibility or bad
weather conditions.
.Work if the detection sensor is not
cleaned or is covered by ice, snow,
mud, or dirt.
.Work if the detection sensor is
covered up, such as with a sticker,
magnet, or metal plate.
.Work if the area surrounding the
detection sensor is damaged or not
properly repaired.
(Continued)
Warning (Continued)
Complete attention is always required
while driving, and you should be ready to
take action and apply the brakes and/or
steer the vehicle to avoid crashes.
Audible Alert
Some driver assistance features alert the
driver of obstacles by beeping. To change
the volume of the warning chime, see
“Comfort and Convenience” underVehicle
Personalization 0110.
Cleaning
Depending on vehicle options, keep these
areas of the vehicle clean to ensure the best
driver assistance feature performance. Driver
Information Center (DIC) messages may
display when the systems are unavailable or
blocked.
.Front and rear bumpers and the area
below the bumpers
.Front grille and headlamps
.Front camera lens in the front grille or
near the front emblem

Chevrolet Trailblazer Owner Manual (GMNA-Localizing-U.S./Canada-
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Driving and Operating 221
.Front side and rear side panels
.Outside of the windshield in front of the
rearview mirror
.Rear side corner bumpers
.Rear Vision Camera above the license
plate
Assistance Systems for Parking or
Backing
If equipped, the Rear Vision Camera (RVC),
Rear Park Assist (RPA), and Rear Cross Traffic
Alert (RCTA) may help the driver park or
avoid objects. Always check around the
vehicle when parking or backing.
Rear Vision Camera (RVC)
When the vehicle is shifted into R (Reverse),
the RVC displays an image of the area
behind the vehicle in the infotainment
display. The previous screen displays when
the vehicle is shifted out of R (Reverse) after
a short delay. To return to the previous
screen sooner, press Home or Back button
on the infotainment display, shift into
P (Park), or reach a vehicle speed of
approximately 12 km/h (8 mph) while in D
(Drive).
1. View Displayed by the Rear VisionCamera
1. View Displayed by the Rear VisionCamera
2. Corners of the Rear Bumper
Displayed images may be farther or closer
than they appear. The area displayed is
limited and objects that are close to either
corner of the bumper or under the bumper
do not display.
A warning triangle may display to show
that RPA or RCTA has detected an object.
This triangle changes from amber to red and
increases in size the closer the object.
{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.
Park Assist
If equipped, Rear Parking Assist (RPA)
system, it assists the driver with parking
and avoiding objects while in R (Reverse).

Chevrolet Trailblazer Owner Manual (GMNA-Localizing-U.S./Canada-
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222 Driving and Operating
RPA operates at speeds less than 8 km/h
(5 mph), and the sensors on the rear bumper
detect objects up to 2.5 m (8 ft) behind the
vehicle, and at least 25 cm (10 in) off the
ground. The distance objects can be detected
may be less during warmer or humid
weather.
Blocked sensors will not detect objects and
can also cause false detections. Keep the
sensors clean of mud, dirt, snow, ice, and
slush; and clean sensors after a car wash in
freezing temperatures.
{Warning
The Park Assist system does not detect
children, pedestrians, bicyclists, animals,
or objects located below the bumper or
that are too close or too far from the
vehicle. It is not available at speeds
greater than 8 km/h (5 mph). To prevent
injury, death, or vehicle damage, even
with Park Assist, always check the area
around the vehicle and check all mirrors
before moving forward or backing.
The instrument cluster may have a Park
Assist display with bars that show“distance
to object” and object location information
for the Park Assist system. As the object
gets closer, more bars light up and the bars
change color from yellow to amber to red.
When an object is first detected in the rear,
one beep will be heard from the rear. When
an object is very close (< 0.6 m (2 ft) in the
vehicle rear, five beeps will sound from
the rear.
Rear Cross Traffic Alert (RCTA)
If equipped, when the vehicle is shifted into
R (Reverse), RCTA displays a red warning
triangle with a left or right pointing arrow
on the infotainment display to warn of
traffic coming from the left or right. This
system detects objects coming from up to
20 m (65 ft) from the left or right side of the vehicle. When an object is detected,
either three beeps sound from the left or
right depending on the direction of the
detected vehicle.
Use caution while backing up when towing
a trailer, as the RCTA detection zones that
extend out from the back of the vehicle do
not move further back when a trailer is
towed.
Turning the Features On or Off
RCTA and Rear Park Assist symbols can be
turned on or off through vehicle
personalization. See
“Collision/Detection
Systems” underVehicle Personalization
0 110.
Turn off RPA when towing a trailer.
Assistance Systems for Driving
If equipped, when driving the vehicle in a
forward gear, Forward Collision Alert (FCA),
Lane Departure Warning (LDW), Side Blind
Zone Alert (SBZA) Lane Keep Assist (LKA),
Lane Change Alert (LCA), Automatic
Emergency Braking (AEB), and/or the Front
Pedestrian Braking (FPB) System can help to
avoid a crash or reduce crash damage.

Chevrolet Trailblazer Owner Manual (GMNA-Localizing-U.S./Canada-
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224 Driving and Operating
Also, eight rapid high-pitched beeps will
sound from the front. When this Collision
Alert occurs, the brake system may prepare
for driver braking to occur more rapidly
which can cause a brief, mild deceleration.
Continue to apply the brake pedal as
needed. Cruise control may be disengaged
when the Collision Alert occurs.
Tailgating Alert
The vehicle ahead indicator will display
amber when you are following a vehicle
ahead too closely.
Selecting the Alert Timing
The Collision Alert control is on the steering
wheel. Press
[to set the FCA timing to
Far, Medium, or Near. The first button press
shows the current setting on the DIC.
Additional button presses will change this
setting. The chosen setting will remain until
it is changed and will affect the timing of
both the Collision Alert and the Tailgating
Alert features. The timing of both alerts will vary based on vehicle speed. The faster the
vehicle speed, the farther away the alert will
occur. Consider traffic and weather
conditions when selecting the alert timing.
The range of selectable alert timings may
not be appropriate for all drivers and driving
conditions.
If your vehicle is equipped with Adaptive
Cruise Control (ACC), changing the FCA
timing setting automatically changes the
following gap setting (Far, Medium,
or Near).
Following Distance Indicator
The following distance to a moving vehicle
ahead in your path is indicated in following
time in seconds on the Driver Information
Center (DIC). See
Driver Information Center
(DIC) (Base Level) 0104 or
Driver Information Center (DIC) (Uplevel)
0 107. The minimum following time is
0.5 seconds away. If there is no vehicle
detected ahead, or the vehicle ahead is out
of sensor range, dashes will be displayed.
Unnecessary Alerts
FCA may provide unnecessary alerts for
turning vehicles, vehicles in other lanes,
objects that are not vehicles, or shadows.
These alerts are normal operation and the
vehicle does not need service.
Cleaning the System
If the FCA system does not seem to operate
properly, this may correct the issue:
.Clean the outside of the windshield in
front of the rearview mirror.
.Clean the entire front of the vehicle.
.Clean the headlamps.
Automatic Emergency
Braking (AEB)
If the vehicle has Forward Collision Alert
(FCA), it also has AEB, which includes
Intelligent Brake Assist (IBA). When the
system detects a vehicle ahead in your path
that is traveling in the same direction that
you may be about to crash into, it can
provide a boost to braking or automatically
brake the vehicle. This can help avoid or
lessen the severity of crashes when driving
in a forward gear. Depending on the
situation, the vehicle may automatically

Chevrolet Trailblazer Owner Manual (GMNA-Localizing-U.S./Canada-
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Driving and Operating 227
detected directly in front of the vehicle, the
pedestrian ahead indicator will display
amber.
Front Pedestrian Alert
When the vehicle approaches a pedestrian
ahead too rapidly, the red FPB alert display
will flash on the windshield. Eight rapid
high-pitched beeps will sound from the
front. When this Pedestrian Alert occurs, the
brake system may prepare for driver braking
to occur more rapidly which can cause a
brief, mild deceleration. Continue to apply
the brake pedal as needed. Cruise control
may be disengaged when the Front
Pedestrian Alert occurs.
Automatic Braking
If FPB detects it is about to crash into a
pedestrian directly ahead, and the brakes
have not been applied, FPB may
automatically brake moderately or brake
hard. This can help to avoid some very lowspeed pedestrian crashes or reduce
pedestrian injury. FPB can automatically
brake to detected pedestrians between
8 km/h (5 mph) and 80 km/h (50 mph).
Automatic braking levels may be reduced
under certain conditions, such as higher
speeds.
If this happens, Automatic Braking may
engage the Electric Parking Brake (EPB) to
hold the vehicle at a stop. Release the EPB.
A firm press of the accelerator pedal will
also release Automatic Braking and the EPB.
{Warning
FPB may alert or automatically brake the
vehicle suddenly in situations where it is
unexpected and undesired. It could falsely
alert or brake for objects similar in shape
or size to pedestrians, including shadows.
This is normal operation and the vehicle
does not need service. To override
Automatic Braking, firmly press the
accelerator pedal, if it is safe to do so.
Automatic Braking can be disabled through
vehicle personalization. See “Front Pedestrian
Detection” in“Collision/Detection Systems”
under Vehicle Personalization 0110.
{Warning
Using the Front Pedestrian Braking
system while towing a trailer could cause
you to lose control of the vehicle and
crash. Turn the system to Alert or Off
when towing a trailer.
Cleaning the System
If FPB does not seem to operate properly,
cleaning the outside of the windshield in
front of the rearview mirror may correct the
issue.
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. 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 and
a vehicle is also detected on the same side,
the display will flash as an extra warning
not to change lanes. Since this system is
part of the Lane Change Alert (LCA) system,
read the entire LCA section before using this
feature.

Chevrolet Trailblazer Owner Manual (GMNA-Localizing-U.S./Canada-
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228 Driving and Operating
Lane Change Alert (LCA)
If equipped, the LCA system is a
lane-changing aid that assists drivers with
avoiding lane change crashes that occur with
moving vehicles in the side blind zone (or
spot) areas or with vehicles rapidly
approaching these areas from behind. The
LCA warning display will light up in the
corresponding outside mirror and will flash
if the turn signal is on.
{Warning
LCA does not alert the driver to vehicles
outside of the system detection 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.LCA Detection Zones
1. SBZA Detection Zone
2. LCA Detection Zone
The LCA 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.
The Side Blind Zone Alert (SBZA) warning
area starts at approximately the middle of
the vehicle and goes back 5 m (16 ft). Drivers
are also warned of vehicles rapidly
approaching from up to 70 m (230 ft) behind
the vehicle.
How the System Works
The LCA symbol lights up in the outside
mirrors when the system detects a moving
vehicle in the next lane over that is in the side blind zone or rapidly approaching that
zone from behind. A lit LCA symbol indicates
it may be unsafe to change lanes. Before
making a lane change, check the LCA
display, check mirrors, glance over your
shoulder, and use the turn signals.
Left Outside Mirror
DisplayRight Outside Mirror Display
When the vehicle is started, both outside
mirror LCA displays will briefly come on to
indicate the system is operating. When the
vehicle is in a forward gear, the left or right
outside mirror display will light up if a
moving vehicle is detected in the next lane
over in that blind zone or rapidly
approaching that zone. If the turn signal is
activated in the same direction as a
detected vehicle, this display will flash as an
extra warning not to change lanes.

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230 Driving and Operating
Warning (Continued)
.Provide an alert or enough steering
assist to avoid a lane departure or
crash.
.Detect lane markings under poor
weather or visibility conditions. This
can occur if the windshield or
headlamps are blocked by dirt, snow,
or ice; if they are not in proper
condition; or if the sun shines directly
into the camera.
.Detect road edges.
.Detect lanes on winding or hilly roads.
If LKA only detects lane markings on one
side of the road, it will only assist or
provide an LDW alert when approaching
the lane on the side where it has
detected a lane marking. Even with LKA
and LDW, you must steer the vehicle.
Always keep your attention on the road
and maintain proper vehicle position
within the lane, or vehicle damage,
injury, or death could occur. Always keep
the windshield, headlamps, and camera
sensors clean and in good repair. Do not
(Continued)
Warning (Continued)
use LKA in bad weather conditions or on
roads with unclear lane markings, such as
construction zones.
{Warning
Using LKA while towing a trailer or on
slippery roads could cause loss of control
of the vehicle and a crash. Turn the
system off.
How the System Works
LKA uses a camera sensor installed on the
windshield ahead of the rearview mirror to
detect lane markings. It may provide brief
steering assist if it detects an unintended
lane departure. It may further provide an
audible alert or the driver seat may pulse
indicating that a lane marking has been
crossed.
To turn LKA on and off, press
Aon the
center stack. If equipped, the indicator light
on the button comes on when LKA is on and
turns off when LKA is disabled. When on,
Ais white, if equipped,
indicating that the system is not ready to
assist.
Ais green if LKA is ready to
assist. LKA may assist by gently turning the
steering wheel if the vehicle approaches a
detected lane marking.
Ais amber when
assisting. It may also provide a Lane
Departure Warning (LDW) alert by flashing
Aamber if the vehicle crosses a
detected lane marking. Additionally, there
may be three beeps, on the right or left,
depending on the lane departure direction.
Take Steering
The LKA system does not continuously steer
the vehicle. If LKA does not detect active
driver steering, an alert and chime may be
provided. Steer the vehicle to dismiss. LKA
may become temporarily unavailable after
repeated take steering alerts.
When the System Does Not Seem to
Work Properly
The system performance may be
affected by:
.Close vehicles ahead.
.Sudden lighting changes, such as when
driving through tunnels.
.Banked roads.