2021 CADILLAC CT4 brake sensor

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
276 DRIVING AND OPERATING
Warning (Continued)
when driving may result in injury,
death, or vehicle damage. See
Defensive Driving0204.
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. (Continued)
Warning (Continued)
.Work if the detection sensor
viewing zone is interrupted by an
installed accessory, such as a
bike rack, or hitch mounted
cargo carrier.
.Work if the area surrounding the
detection sensor is damaged or
not properly repaired.
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 or Safety Alert Seat
Some driver assistance features alert
the driver of obstacles by beeping. To
change the volume of the warning
chime, see “Comfort and Convenience ”
under Vehicle Personalization 0117.
If equipped with the Safety Alert Seat,
the driver seat cushion may provide a
vibrating pulse alert instead of
beeping. To change this, see
“Collision/Detection Systems” under
Vehicle Personalization 0117. 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.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
280 DRIVING AND OPERATING
When an object is very close to the
vehicle rear (<0.6m (2 ft)), five beeps
will sound from the rear followed by a
continuous beep from the rear,
or both sides of the Safety Alert Seat
will pulse five times. When an object
is very close to the vehicle front
(<0.3m (1 ft)), a continuous beep will
sound from the front, or both sides of
the Safety Alert Seat will pulse five
times. Beeps for FPA are higher
pitched than for RPA.
When the System Does Not Seem to
Work Properly
The following messages may be
displayed on the DIC:
SERVICE PARKING ASSIST :If this
message occurs, check the following
conditions:
.The sensors are not clean. Keep the
vehicle's rear bumper free of mud,
dirt, snow, ice, and slush. For
cleaning instructions, see Exterior
Care 0370.
.The Park Assist sensors are covered
by frost or ice. Frost or ice can form
around and behind the sensors and
may not always be seen; this can
occur after washing the vehicle in cold weather. The message may not
clear until the frost or ice has
melted.
If the above conditions do not exist,
take the vehicle to your dealer to
repair the system.
PARK ASSIST OFF : If the PA system
does not activate due to a temporary
condition, the message displays on the
DIC. This can occur under the
following conditions:
.The driver has disabled the system.
.An object was hanging out of the
trunk during the last drive cycle.
Once the object is removed, RPA
will return to normal operation.
.The bumper is damaged. Take the
vehicle to your dealer to repair the
system.
.Other conditions, such as vibrations
from a jackhammer or the
compression of air brakes on a very
large truck, are affecting system
performance. Backing Warning and Reverse
Automatic Braking
Vehicles with Adaptive Cruise Control
(ACC) have the Backing Warning
System and Reverse Automatic
Braking (RAB) system. The Backing
Warning part of this system can warn
of rear objects when backing up at
speeds greater than 8 km/h (5 mph),
and RAB may automatically brake
hard at speeds between 1–32 km/h
(0.5–20 mph).
The Backing Warning System will
beep once from the rear when an
object is first detected, or pulse twice
on both sides of the Safety Alert Seat.
When the system detects a potential
crash, beeps will be heard from the
rear, or five pulses will be felt on both
sides of the Safety Alert Seat. There
may also be a brief, sharp application
of the brakes.
{Warning
The Backing Warning System only
operates at speeds greater than
8 km/h (5 mph). It does not detect
children, pedestrians, bicyclists,
(Continued)

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
284 DRIVING AND OPERATING
Detecting the Vehicle Ahead
FCA warnings will not occur unless
the FCA system detects a vehicle
ahead. When a vehicle is detected, the
vehicle ahead indicator will display
green. Vehicles may not be detected
on curves, highway exit ramps,
or hills, due to poor visibility; or if a
vehicle ahead is partially blocked by
pedestrians or other objects. FCA will
not detect another vehicle ahead until
it is completely in the driving lane.
{Warning
FCA does not provide a warning to
help avoid a crash, unless it detects
a vehicle. FCA may not detect a
vehicle ahead if the FCA sensor is
blocked by dirt, snow, or ice, or if
the windshield is damaged. It may
also not detect a vehicle on winding(Continued)
Warning (Continued)
or hilly roads, or in conditions that
can limit visibility such as fog, rain,
or snow, or if the headlamps or
windshield are not cleaned or in
proper condition. Keep the
windshield, headlamps, and FCA
sensors clean and in good repair.
Collision Alert
With Head-Up Display
Without Head-Up Display When your vehicle approaches
another detected vehicle too rapidly,
the red FCA display will flash on the
windshield. Also, eight rapid
high-pitched beeps will sound from
the front, or both sides of the Safety
Alert Seat will pulse five times. 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.
Tailgating Alert
The vehicle ahead indicator will
display amber when you are following
a vehicle ahead too closely.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
DRIVING AND OPERATING 285
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)
0107 or
Driver Information Center (DIC)
(Uplevel) 0110. 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)
The AEB system may help avoid or
reduce the harm caused by front-end
crashes. AEB also 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 brake
moderately or hard. This automatic
emergency braking can only occur if a
vehicle is detected. This is shown by

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
DRIVING AND OPERATING 287
AEB and IBA can be disabled through
vehicle personalization. See“Collision/
Detection Systems” underVehicle
Personalization 0117.
{Warning
Using AEB or IBA while towing a
trailer could cause you to lose
control of the vehicle and crash.
Turn the system to Alert, or if the
vehicle has ACC to Off, when
towing a trailer.
A system unavailable message may
display if:
.The front of the vehicle or
windshield is not clean.
.Heavy rain or snow is interfering
with object detection.
.There is a problem with the
StabiliTrak/Electronic Stability
Control (ESC) system.
The AEB system does not need
service.
Front Pedestrian Braking
(FPB) System
If equipped, the FPB system may help
avoid or reduce the harm caused by
front-end crashes with nearby
pedestrians when driving in a forward
gear. FPB displays an amber indicator,
~, when a nearby pedestrian is
detected ahead. When approaching a
detected pedestrian too quickly, FPB
provides a red flashing alert on the
windshield and rapidly beeps or pulses
the driver seat. FPB can provide a
boost to braking or automatically
brake the vehicle. This system
includes Intelligent Brake Assist (IBA),
and the Automatic Emergency Braking
(AEB) System may also respond to
pedestrians. See Automatic Emergency
Braking (AEB) 0285.
The FPB system can detect and alert
to pedestrians in a forward gear at
speeds between 8 km/h (5 mph) and
80 km/h (50 mph). During daytime
driving, the system detects
pedestrians up to a distance of
approximately 40 m (131 ft). During
nighttime driving, system performance
is very limited. If the vehicle is equipped with the Night Vision
system, during nighttime driving, the
vehicle can detect and alert to
pedestrians whenever in a
forward gear.
{Warning
FPB does not provide an alert or
automatically brake the vehicle,
unless it detects a pedestrian. FPB
may not detect pedestrians,
including children:
.When the pedestrian is not
directly ahead, fully visible,
or standing upright, or when part
of a group.
.Due to poor visibility, including
nighttime conditions, fog, rain,
or snow.
.If the FPB sensor is blocked by
dirt, snow, or ice.
.If the headlamps or windshield
are not cleaned or in proper
condition.
(Continued)

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 12/4/20
288 DRIVING AND OPERATING
Warning (Continued)
Be ready to take action and apply
the brakes. For more information,
seeDefensive Driving 0204. Keep
the windshield, headlamps, and FPB
sensor clean and in good repair.
FPB can be set to Off, Alert, or Alert &
Brake through vehicle personalization.
See “Front Pedestrian Detection ”in
“Collision/Detection Systems” under
Vehicle Personalization 0117.
Detecting the Pedestrian Ahead
FPB alerts and automatic braking will
not occur unless the FPB system
detects a pedestrian. When a nearby
pedestrian is detected in front of the
vehicle, the pedestrian ahead indicator
will display amber.
Front Pedestrian Alert
With Head-Up Display
Without Head-Up Display
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,
or both sides of the Safety Alert Seat
will pulse five times. 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 low speed 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 also
equipped with the Night Vision
system, pedestrians detected by the
Night Vision system will not cause
automatic braking to occur.
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.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
324 VEHICLE CARE
Caution
Continuing to drive with worn-out
brake linings could result in costly
brake repairs.
Some driving conditions or climates
can cause a brake squeal when the
brakes are first applied, clearing up
following several applications. This
does not mean something is wrong
with the brakes.
Properly torqued wheel nuts are
necessary to help prevent brake
pulsation. When tires are rotated,
inspect brake linings for wear and
evenly tighten wheel nuts in the
proper sequence to torque
specifications. See Capacities and
Specifications 0396.
Brake pads should be replaced as
complete axle sets.
Brake Pedal Travel
See your dealer if the brake pedal does
not return to normal height, or if
there is a rapid increase in pedal
travel. This could be a sign that brake
service may be required.
Replacing Brake System Parts
Always replace brake system parts
with new, approved replacement parts.
If this is not done, the brakes may not
work properly. The braking
performance can change in many
ways if the wrong brake parts are
installed or if parts are improperly
installed.
Brake Pad Life System (If
Equipped)
When to Change Brake Pads
This vehicle has a system that
estimates the remaining life of the
front and rear brake pads. Brake pad
life is displayed in the Driver
Information Center (DIC), along with
a percentage for each axle. The system
must be reset every time the brake
pads are changed.
When the system has determined that
the brake pads need to be replaced, a
message will display, which may
include mileage remaining.
Brake pads should always be replaced
as complete axle sets.
How to Reset the Brake Pad Life
System
The system will automatically detect
when significantly worn brake pads
and sensors are replaced. When the
ignition is turned on after new pads
and sensors are installed, a message
will display. Follow the prompts to
reset the system.
The brake pad life system can also be
manually reset: 1. Display Brake Pad Life on the DIC. See Driver Information Center (DIC)
(Base Level) 0107 or
Driver Information Center (DIC)
(Uplevel) 0110.
2. Press the thumbwheel. Select front or rear pads as appropriate.
3. Select YES on the confirmation message. Repeat for pads on the
other axle if they were also
replaced.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
VEHICLE CARE 325
How to Disable the Brake Pad
Life System
The brake pad life system can be
turned off. This may be necessary if
aftermarket brake pads without wear
sensors are installed. When the
system is turned off, the front and
rear brake pad life percentages will
not display. However, the built-in wear
indicators that make a high-pitched
warning sound when the brake pads
are worn can still determine when the
pads should be replaced. SeeBrakes
0 323.
To turn off the brake pad life system: 1. Display Brake Pad Life on the DIC. See Driver Information Center (DIC)
(Base Level) 0107 or
Driver Information Center (DIC)
(Uplevel) 0110.
2. Select DISABLE.
To turn the brake pad life system back
on, follow the above steps but select
ENABLE in Step 2.
Brake Fluid
The brake master cylinder reservoir is
filled with GM approved DOT 4 brake
fluid as indicated on the reservoir cap.
See Engine Compartment Overview
0 309 for the location of the reservoir.
Checking Brake Fluid
With the vehicle in P (Park) on a level
surface, the brake fluid level should be
between the minimum and maximum
marks on the brake fluid reservoir.
There are only two reasons why the
brake fluid level in the reservoir may
go down:
.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
0 99.