2023 MAZDA CX3 brake sensor

NOTE
The distance-between-vehicles differs depending on the vehicle speed, and the
slower the vehicle speed, the shorter the distance.
When the ignition is switched to ACC or OFF, the set distance-between-vehicles is
taken over automatically even when the engine is started again.

The function is temporarily canceled
Headway control function
When the following operations are performed, the headway control function is
temporarily canceled and the TJA set indication (green) changes to the TJA standby
indication (white) at the same time.
The CANCEL switch is pressed one time.The brake pedal is depressed.The selector lever is in the P, N, or R position.

In the following cases, the TJA cancel indication is displayed and a sound is activated
one time.
The DSC has operated.The Smart Brake Support (SBS) has operated.The vehicle is driven on a downslope for a long time.There is a problem with the system.The front radar sensor cannot detect target objects (during rain, fog, snow or other
inclement weather conditions, or when the radiator grille is dirty).
The parking brake is applied.Any of the doors is opened.The driver's seat belt is unfastened.The operation frequency of the braking by the TJA control is high.The parking brake is automatically applied during stop hold control.

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Smart Brake Support(SBS)
*
▼Smart Brake Support (SBS)
The SBS is a system designed to detect
target objects using sensors and
cameras equipped on the vehicle, and
to reduce damage in the event of a
collision by operating the brake control
if there is the possibi
lity of your vehicle
colliding with a target object.
One part of the SBS functions when
you are driving forward and the other
part functions when you are driving in
reverse.
Refer to Forward drive detection on
page 4-156.
Refer to Reverse drive detection on
page 4-158.
▼ Forward drive detection
When you are driving forward, the
following functions of the Smart Brake
Support (SBS) operate.
Forward detection function
WARNING
Do not rely completely on the
SBS:
The SBS is only designed to reduce
damage in the event of a collision.
The system may not operate normally
depending on the target object,
weather conditions, or traffic
conditions. Over reliance on the
system leading to the accelerator pedal
or brake pedal being mistakenly
operated could result in an accident.
CAUTION
In the following cases, turn the SBS off
to prevent a mis-operation.
 The vehicle is being towed or towing
another vehicle.
 The vehicle is driven on rough roads
such as in areas where there is grass
and foliage or off-road.
Refer to Stopping the Smart Brake
Support (SBS) System Operation on
page 4-163.
Forward detection function
The forward detection function is
designed to reduce damage in the
event of a collision with target objects
at the front.
The forward detection function detects
target objects (vehicles ahead,
pedestrians, and bicycles) using the
front radar sensor and the Forward
Sensing Camera (FSC). If there is a
possibility of your vehicle colliding with
a target object at the front, you are
notified of possible danger by a
warning sound and a warning
indication on the display.
Furthermore, if the possibility of a
collision increases, the brake control is
performed to reduce damage in the
event of a collision. In addition, when
the driver depresses the brake pedal,
the brakes are applied firmly and
quickly to assist.

(Vehicles with Driver Monitoring
(DM))
If the system determines that the driver
is not paying attention to the road, it
activates the collision warning earlier
than normal.
Operation conditions
The forward detection function
operates when all of the following
conditions are met.
The ignition is switched ON.The SBS is on.(Object is vehicle ahead)
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The vehicle speed is about 4 km/h
(3 mph) or higher.
(Object is a pedestrian or bicycle)
The vehicle speed is between about
10 and 80 km/h (6.3 to 49 mph).
The DSC does not operate.
NOTE
When any of the following
conditions is met, the forward
detection function may not operate.
If there is the possibility of hitting
only a part of a vehicle or
obstruction ahead.
You are driving your vehicle at the
same speed as the vehicle ahead.
When the driver deliberately
performs driving operations
(accelerator operation, steering
wheel operation).
The accelerator pedal is depressed
abruptly.
The brake pedal is depressed.The steering wheel is being
operated.
The selector lever is being shifted.The turn signal lever is being
operated.
Warnings and messages, such as a
dirty windshield, related to the
Forward Sensing Camera (FSC) or
front radar sensor are being
displayed on the multi-information
display.
When any of the following
conditions is met, the forward
detection function may operate.
There is an object in the road at
the entrance to a curve (including
guardrails and snow banks).
Passing an approaching vehicle
while rounding a curve.
When crossing a narrow bridge,
going under a low overhang, or
passing through a narrow gate, a
car washing machine, or tunnel.
When passing through a toll gate.When entering an underground
parking area.
There is a metal object, bump, or a
protruding object on the road.
If you suddenly come close to a
vehicle ahead.
An animal, wall, or standing tree is
detected.
While the system is operating, the
driver is notified by the
multi-information display and the
active driving display.
If a malfunction is detected or the
system temporarily stops the
function due to dirt on the sensors or
cameras, the i-ACTIVSENSE warning
light turns on and a message is
displayed on the multi-information
display.
If the vehicle is stopped by the SBS
brake operation and the brake pedal
is not depressed, the SBS brake is
automatically released after about 2
seconds.
Collision warning
If there is the possibility of your vehicle
colliding with a target object at the
front, the warning sound is activated
continuously and a warning is
displayed on the multi-information
display and the active driving display.
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Multi-information display
1. “BRAKE!” message is displayed

Active driving display
1. “BRAKE!” message is displayed
NOTE
During brake control and brake assist
operation, the collision warning
sound is activated intermittently.
The operation distance and volume
of the collision warning can be
changed.
Refer to the Settings section in the
Mazda Connect Owner's Manual.
▼Reverse drive detection*
When you are driving in reverse, the
following functions of the Smart Brake
Support (SBS) operate.
Rearward detection functionRear crossing
WARNING
Do not rely completely on the
SBS:
The SBS is only designed to reduce
damage in the event of a collision.
Over reliance on the system leading to
the accelerator pedal or brake pedal
being mistakenly operated could result
in an accident.
Heed the following cautions so that
the SBS can operate normally:
Do not apply stickers (including
transparent stickers) to the areas
around the rear side radar sensors
and the rear ultrasonic sensors.
Otherwise, a rear side radar sensor
and a rear ultrasonic sensor may not
be able to detect vehicles and
obstructions correctly which could
result in an accident.
 Do not disassemble the rear side
radar sensors and rear ultrasonic
sensors.
 If you recognize scratches around the
rear side radar sensors and rear
ultrasonic sensors, stop using the SBS
immediately and always have the
vehicle inspected by an Authorized
Mazda Dealer.
Refer to Stopping the Smart Brake
Support (SBS) System Operation on
page 4-163.
 Consult an Authorized Mazda Dealer
for rear bumper removal/
installation.
Do not modify the suspension:
If the vehicle height or inclination is
changed, the SBS may not operate
correctly because it cannot detect
obstructions correctly.
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Do not hit the rear side radar sensors
and rear ultrasonic sensors forcefully:
When washing the vehicle, do not
spray highly pressurized water against
the rear side radar sensors and the rear
ultrasonic sensors, or rub them
strongly. In addition, do not hit the rear
bumper forcefully when loading and
unloading cargo. Otherwise, the
system will be unable to detect
obstructions correctly and the SBS may
not operate normally.
CAUTION
In the following cases, turn the SBS
off to prevent a mis-operation.
 A trailer is pulled or an accessory
such as a bicycle carrier is installed
to the rear of the vehicle.
 The vehicle is driven on rough
roads such as in areas where there
is grass and foliage or off-road.
Refer to Stopping the Smart Brake
Support (SBS) System Operation
on page 4-163.
 Always use tires for all wheels that
are of the specified size, and the
same manufacture, brand, and tread
pattern. In addition, do not use tires
with significantly different wear
patterns on the same vehicle. If such
improper tires are used, the SBS may
not operate normally.
Rearward detection function
The rearward detection function is
designed to reduce damage in the
event of a collision with a target object
when reversing.
The rearward detection function
detects obstructions using the rear
ultrasonic sensors. In addition, if there
is the possibility of your vehicle
colliding with a target object at the rear
while you are driving in reverse, you
are notified of possible danger by a
warning sound and a warning
indication on the display.
Furthermore, if the possibility of a
collision increases, brake control is
performed to reduce damage in the
event of a collision.
WARNING
Always check the surrounding area
visually when reversing the vehicle:
The operation of the rearward
detection function has certain
limitations. Therefore, the function
might not operate or it might be
delayed even if there is a target object
at the rear of your vehicle. Always
make it your responsibility as a driver
to check the rear.
Operation conditions
The rearward detection function
operates when all of the following
conditions are met.
The engine is running.The SBS is on.The selector lever is in the R position.The vehicle speed is about 2 km/h
(2 mph) to 8 km/h (4 mph).
There is no problem with the DSC.
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NOTE
When any of the following
conditions is met, the rearward
detection function may not operate.
Directly after the engine starts.The height of the obstruction is
low such as low walls or trucks
with low loading platforms.
The height of the obstruction is
high such as trucks with high
loading platforms.
The obstruction is not as large as a
vehicle or wall.
The obstruction is thin such as a
signpost.
The surface of the obstruction is
not pointed vertically relative to
your vehicle.
The obstruction is soft such as a
hanging curtain or snow stuck to a
vehicle.
The obstruction is shaped
irregularly.
The obstruction is extremely close.When any of the following
conditions is met, the rearward
detection function may not operate
normally.
Snow, ice, or mud adheres to the
area around a rear ultrasonic
sensor.
The vehicle posture is unstable due
to sudden operation of the steering
wheel, accelerator pedal, or brake
pedal.
There is another obstruction near
one obstruction.
During inclement weather such as
rain, fog , and snow.
High or low humidity.High or low temperatures.Strong winds.The path of travel is not flat.
Heavy luggage is loaded in the
luggage compartment or on the
rear seat and the vehicle is tilted.
Objects such as a wireless antenna,
fog light, or illuminated license
plate is installed near a rear
ultrasonic sensor.
The orientation of a rear ultrasonic
sensor has deviated for reasons
such as a collision.
The vehicle is affected by other
sound waves such as the horn,
engine noise, or rear ultrasonic
sensor of another vehicle.
When any of the following
conditions is met, the rearward
detection function may operate.
Reversing towards a steep
ascending slope.
There are grating, wheel blocks, a
road curb, or a bump.
There is a hanging curtain or
railroad crossing gate.
Reversing near objects such as
foliage, barriers, vehicles, walls, or
fences.
The vehicle is driven on rough
roads such as in areas where there
is grass and foliage or off-road.
When reversing through low gates,
narrow gates, car washing
machines, tunnels, or into a
mechanical parking garage.
A towing bar is installed or a trailer
is connected.
If the vehicle is stopped by the SBS
brake operation and the brake pedal
is not depressed, the SBS brake is
automatically released after about 2
seconds.
Collision warning
If there is the possibility of your vehicle
colliding with a vehicle approaching
from the rear on the left or right, or
from the rear while you are driving in
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reverse, a warning sound is activated
continuously and a warning is
displayed on the multi-information
display and the active driving display.
Multi-information display
1. “BRAKE!” message is displayed

Active driving display
1. “BRAKE!” message is displayed
NOTE
During brake control, the collision
warning sound is activated
intermittently.
Rear crossing
The Rear Crossing detection function is
designed to reduce the damage in the
event of a collision with a vehicle
approaching from the rear sides while
driving in reverse.
The Rear Crossing detection function
detects approaching vehicles using the
rear side radar sensors. If there is the
possibility of your vehicle colliding with
a vehicle approaching from the rear
sides while you are driving in reverse,
you are notified of possible danger by
a warning sound and a warning
indication on the display.
Furthermore, if the possibility of a
collision increases, brake control is
performed to reduce damage in the
event of a collision.
WARNING
Always check the surrounding area
visually when reversing the vehicle:
The operation of the Rear Crossing
detection function has certain
limitations. Therefore, the function
might not operate or it might be
delayed even if there is a vehicle
passing through the rear of your
vehicle. Always make it your
responsibility as a driver to check the
rear.
Do not rely completely on the Rear
Crossing detection function:
The Rear Crossing detection function
operates on vehicles while you are
driving in reverse. It will not operate on
walls, pedestrians, or animals.
Operation conditions
The Rear Crossing detection function
operates when all of the following
conditions are met.
The engine is running.The SBS is on.The selector lever is in the R position.The vehicle speed is about 10 km/h
(6.2 mph) or slower.
The vehicle speed of an approaching
vehicle is about 3 km/h (2 mph) or
faster.
There is no problem with the DSC.
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Front Radar Sensor*
▼Front Radar Sensor
Your vehicle is equipped with a front
radar sensor.
The following systems also use the
front radar sensor.
Distance & Speed Alert (DSA)Mazda Radar Cruise Control with
Stop & Go function (MRCC with
Stop & Go function)
Tra ffi c
Jam Assist (TJA)Smart Brake Support (SBS) forward
drive detection
The front radar sensor functions by
detecting the radio waves reflected off
a vehicle ahead or an obstruction sent
from the radar sensor.
The front radar sensor is mounted
behind the front emblem.
1. Front radar sensor

If “Safety and Driver Support Systems
Temporarily Disabled. Front Radar
Obscured. Drive Safely” is displayed on
the multi-information display of the
instrument cluster, clean the area
around the front radar sensor.
CAUTION
Heed the following precautions to
assure correct operation of each
system.
 Do not adhere stickers (including
transparent stickers) to the surface of
the radiator grille and front emblem
in and around the front radar sensor,
and do not replace the radiator grille
and front emblem with any product
that is not a genuine product
designed for use with the front radar
sensor.
 The front radar sensor includes a
function for detecting soiling of the
radar sensor's front surface and
informing the driver, however,
depending on the conditions, it may
require time to detect or it may not
detect plastic shopping bags, ice or
snow. If this occurs, the system may
not operate correctly, therefore
always keep the front radar sensor
clean.
 Do not install a grille guard.
 If the front part of the vehicle has
been damaged in a vehicle accident,
the position of the front radar sensor
may have moved. Stop the system
immediately and always have the
vehicle inspected at an Authorized
Mazda Dealer.
 Do not use the front bumper to push
other vehicles or obstructions such
as when pulling out of a parking
space. Otherwise, the front radar
sensor could be hit and its position
deviated.
 Do not remove, disassemble, or
modify the front radar sensor.
 For repairs, replacement or paint
work around the front radar sensor,
consult an Authorized Mazda Dealer.
 Do not modify the suspensions. If
the suspensions are modified, the
vehicle's posture could change and
the front radar sensor may not be
able to correctly detect a vehicle
ahead or an obstruction.
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