sensor MAZDA MODEL CX-3 2021 Service Manual

CAUTION
In the following cases, turn the system off
to prevent a mis-operation:
 The vehicle is being towed or when
towing another vehicle.
 The vehicle is on a chassis roller.
 When driving on rough roads such as in
areas of dense grass or
off-road.
NOTE
The SBS system operates when all of the
following conditions are met:
The ignition is switched ON.
The SBS system is on.
The vehicle speed is about 15 km/h or
faster (10 mph or faster).
The relative speed between your
vehicle and the vehicle ahead is about
15 km/h or faster (10 mph or faster).
The Dynamic Stability Control (DSC)
is not operating.
The SBS system may not operate under
the following conditions:
If the vehicle is accelerated rapidly
and it comes close to a vehicle ahead.
The vehicle is driven at the same
speed as the vehicle ahead.
The accelerator pedal is depressed.
The brake pedal is depressed.
The steering wheel is being operated.
The selector lever is being operated.
The turn signal is being used.
When the vehicle ahead is not
equipped with taillights or the
taillights are turned off.
When warnings and messages, such
as a dirty windshield, related to the
Forward Sensing Camera (FSC) are
being displayed in the center display.
Although the objects which activate the
system are four-wheeled vehicles, the
radar sensor (front) could detect the
following objects, determine them to be
an obstruction, and operate the SBS
system.
Objects on the road at the entrance to
a curve (including guardrails and
snow banks).
A vehicle appears in the opposite lane
while cornering or rounding a curve.
When crossing a narrow bridge.
When passing under a low gate or
through a tunnel or narrow gate.
When entering an underground
parking area.
Metal objects, bumps, or protruding
objects on the road.
If you suddenly come close to a
vehicle ahead.
When driving in areas where there is
high grass or forage.
Two-wheeled vehicles such as
motorbikes or bicycles.
Pedestrians or non-metallic objects
such as standing trees.
When the system operates, the user is
notified by the active driving display.
The SBS warning indication (amber)
turns on when the system has a
malfunction.
Refer to Taking Action on page 7-33.
When Driving
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Radar Sensor (Front)*
Your vehicle is equipped with a radar sensor (front).
The following systems also use the radar sensor (front).
Distance Recognition Support System (DRSS)
Mazda Radar Cruise Control with Stop & Go function (MRCC with Stop & Go function)
Smart Brake Support (SBS)
The radar sensor (front) functions by detecti ng the radio waves reflected off a vehicle ahead
or an obstruction sent from the radar sensor.
The radar sensor (front) is mo unted behind the front emblem.
Radar sensor (front)
If the Smart Brake Support/Smart City Brake Support (SBS/SCBS) Warning Light (amber)
is illuminated, the area around the radar sens or may be dirty. Refer to “Warning Guidance”
in the center display (Type B audio).
Refer to If a Warning Light Turns On or Flashes on page 7-26.
CAUTION
Heed the following precautions to a ssure correct operation of each system.
 Do not adhere stickers (including transparent st ickers) to the surface of the radiator grille
and front emblem in and around the radar sens or (front), and do not replace the radiator
grille and front emblem with any product that is not a genuine product designed for use
with the radar sensor (front).
 The radar sensor (front) includes a function fo r 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 sh opping bags, ice or snow. If this occurs, the
system may not operate correctly, therefore al ways keep the radar sensor (front) clean.
 Do not install a grille guard.
 If the front part of the vehicle has been dama ged in a vehicle accident, the position of the
radar sensor (front) may have moved. Stop the system immediately and always have the
vehicle inspected at an Authorized Mazda Dealer.
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Do not use the front bumper to push other vehi cles or obstructions such as when pulling
out of a parking space. Otherwise, the radar sensor (front) could be hit and its position
deviated.
 Do not remove, disassemble, or modify the radar sensor (front).
 For repairs, replacement or paint work around the radar sensor (front), consult an
Authorized Mazda Dealer.
 Do not modify the suspension. If the suspensi on are modified, the vehicle's posture could
change and the radar sensor (front) may not be able to correctly detect a vehicle ahead or
an obstruction.
NOTE
Under the following conditions, the radar sensor (front) may not be able to detect vehicles
ahead or obstructions correctly and each system may not operate normally.
The rear surface of a vehicle ahead does not reflect radio waves effectively, such as an
unloaded trailer or an automobile with a loading platform covered by a soft top,
vehicles with a hard plastic tailgate, and round-shaped vehicles.
Vehicles ahead with low vehicle height and thus less area for reflecting radio waves.
Visibility is reduced due to a vehicle ahead ca sting off water, snow, or sand from its tires
and onto your windshield.
The luggage compartment is loaded with heavy objects or the rear passenger seats are
occupied.
Ice, snow, or soiling is on the front surface of the front emblem.
During inclement weather such as rain, snow, or sand storms.
When driving near facilities or objects emitting strong radio waves.
Under the following conditions, the radar sensor (front) may not be able to detect vehicles
ahead or obstructions.
The beginning and end of a curve.
Roads with continuous curves.
Narrow lane roads due to road construction or lane closures.
The vehicle ahead enters the radar sensor's blind spot.
The vehicle ahead is running abnormally due to accident or vehicle damage.
Roads with repeated up and down slopes
Driving on poor roads or unpaved roads.
The distance between your vehicle and the vehicle ahead is extremely short.
A vehicle suddenly comes close such as by cutting into the lane.
To prevent incorrect operation of the system, use tires of the same specified size,
manufacturer, brand, and tread pattern on all four wheels. In addition, do not use tires
with significantly different wear patterns or tire pressures on the same vehicle (Including
the temporary spare tire).
If the battery power is weak, the system may not operate correctly.
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If the vehicle is driven on a road with little traffic and few vehicles ahead or obstructions
for the radar sensor (front) to detect, the sensor detects that the radar sensor (front) is
dirty and the Smart Brake Support/Smart City Brake Support (SBS/SCBS) Warning Light
(amber) may be temporarily turned on. Howe ver, it does not indicate a malfunction.
The radar sensors are regulated by the relevant radio wave laws of the country in which
the vehicle is driven. If the vehicle is driven abroad, authorization from the country in
which the vehicle is driven may be required.
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Radar Sensors (Rear)*
Your vehicle is equipped with radar sensors (rear). The follow ing systems also use the radar
sensors (rear).
Blind Spot Monitoring (BSM)
Rear Cross Traffic Alert (RCTA)
The radar sensors (rear) function by detecting the radio waves reflected off a vehicle
approaching from the rear or an obstruction sent from the radar sensor.
Radar sensors (rear)
The radar sensors (rear) are installed inside th e rear bumper, one each on the left and right
sides.
Always keep the surface of the rear bumper near the radar sensors (rear) clean so that the
radar sensors (rear) operate normally. Also , do not apply items such as stickers.
Refer to Exterior Care on page 6-53.
CAUTION
If the rear bumper receives a severe impact, the system may no longer operate normally. Stop
the system immediately and have the vehicle inspected at an Authorized Mazda Dealer.
NOTE
The detection ability of the radar sensors (rear) has limitations. In the following cases,
the detection ability may lower and the system may not operate normally.
The rear bumper near the radar sensors (rear) has become deformed.
Snow, ice or mud adheres to the radar sensors (rear) on the rear bumper.
Under bad weather conditions such as rain, snow and fog.
Under the following conditions, the radar sensors (rear) cannot detect target objects or it
may be difficult to detect them.
Stationary objects on a road or a road side such as small, two-wheeled vehicles,
bicycles, pedestrians, animals, and shopping carts.
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Vehicle shapes which do not reflect radar waves well such as empty trailers with a low
vehicle height and sports cars.
Vehicles are shipped with the direction of the radar sensors (rear) adjusted for each
vehicle to a loaded vehicle condition so that the radar sensors (rear) detect approaching
vehicles correctly. If the direction of the radar sensors (rear) has deviated for some
reason, have the vehicle inspected at an Authorized Mazda Dealer.
For repairs or replacement of the radar sensors (rear), or bumper repairs, paintwork, and
replacement near the radar sensors, consult an Authorized Mazda Dealer.
Turn off the system while pulling a trailer or while an accessory such as a bicycle carrier
is installed to the rear of the vehicle. Otherwise, the radio waves emitted by the radar will
be blocked causing the system to not operate normally.
The radar sensors are regulated by the relevant radio wave laws of the country in which
the vehicle is driven. If the vehicle is driven abroad, authorization from the country in
which the vehicle is driven may be required.
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Tire Pressure Monitoring System*
The Tire Pressure Monitoring System (TPMS) monitors the pressure for each tire.
If tire pressure is too low in one or more tires, the system will inform the driver via the
warning light in the instrument cluster and by the warning beep sound.
Refer to Contact Authorized Mazda Dealer and Have Vehicle Inspected on page 7-29.
Refer to Taking Action on page 7-33.
Refer to Tire Inflation Pressure Warning Beep on page 7-44.

The tire pressure sensors installed on each wheel send tire pressure data by radio signal to
the receiver unit in the vehicle.
Tire pressure sensors
NOTE
When the ambient temperature is low due to seasonal changes, tire temperatures are also
lower. When the tire temperature decreases, the air pressure decreases as well. The TPMS
warning light may illumina te more frequently. Visually inspect the tires daily before driving,
and check tire pressures monthly with a tire pressure gauge. When checking tire pressures,
use of a digital tire pressure gauge is recommended.

TPMS does not alleviate your need to check the pressure and condition of all four tires
regularly.
CAUTION
 Each tire, including the spare (if provided), should be checked monthly when cold and
inflated to the inflation pressure recommended by the vehicle manufacturer on the vehicle
placard or tire inflation pressure label. (If your vehicle has tires of a different size than the
size indicated on the vehicle placard or tire in flation pressure label, you should determine
the proper tire inflation pressure for those tires.)
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As an added safety feature, your vehicle has been equipped with a tire pressure monitoring
system (TPMS) that illuminates a low tire pre ssure telltale when one or more of your tires is
significantly under-inflated. Accordingly, when th e low tire pressure telltale illuminates, you
should stop and check your tires as soon as possible, and inflate them to the proper
pressure. Driving on a significantly under-in flated tire causes the tire to overheat and can
lead to tire failure. Under-inflation also reduce s fuel efficiency and tire tread life, and may
affect the vehicle's handling and stopping ability.
Please note that the TPMS is not a substitute for proper tire maintenance, and it is the
driver's responsibility to maintain correct ti re pressure, even if under-inflation has not
reached the level to trigger illumination of the TPMS low tire pressure telltale.
Your vehicle has also been equipped with a TPMS malfunction indicator to indicate when
the system is not operating properly.
The TPMS malfunction indicator is combined with the low tire pressure telltale. When the
system detects a malfunction, the telltale wi ll flash for approximately one minute and then
remain continuously illuminated. This sequence will continue upon subsequent vehicle
start-ups as long as the malfunction exists. When the malfunction indicator is illuminated,
the system may not be able to detect or signal low tire pressure as intended. TPMS
malfunctions may occur for a variety of reasons, including the installation of replacement
or alternate tires or wheels on the vehicle th at prevent the TPMS from functioning properly.
Always check the TPMS malfunction telltale after replacing one or more tires or wheels on
your vehicle to ensure that the replacement or alternate tires and wheels allow the TPMS to
continue to function properly.
 To avoid false readings, the system samples for a little while before indicating a problem. As
a result it will not instantaneously regi ster a rapid tire deflation or blow out.
▼System Error Activation
When the warning light flashes, there may
be a system malfunction. Consult an
Authorized Mazda Dealer.
A system error activation may occur in the
following cases:
When there is equipment or a device
near the vehicle using the same radio
frequency as that of the tire pressure
sensors.
When a metallic device such as a
non-genuine navigation system is
equipped near the center of the
dashboard, which may block radio
signals from the tire pressure sensor to
the receiver unit.
When using the following devices in the
vehicle that may cause radio
interference with the receiver unit.
A digital device such as a personal
computer.
A current converter device such as a
DC-AC converter.
When excess snow or ice adheres to the
vehicle, especially around the wheels.
When the tire pressure sensor batteries
are exhausted.
When using a wheel with no tire
pressure sensor installed.
When using tires with steel wire
reinforcement in
the sidewalls.
When using tire chains.
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▼Tires and Wheels
CAUTION
When inspecting or adjusting the tire air
pressures, do not apply excessive force to
the stem part of the wheel unit. The stem
part could be damaged.
Changing tires and wheels
The following proced
ure allows the TPMS
to recognize a tire pressure sensor's unique
ID signal code whenever tires or wheels
are changed, such as changing to and from
winter tires.
NOTE
Each tire pressure sensor has a unique ID
signal code. The signal code must be
registered with the TPMS before it can
work. The easiest way to do it is to have
an Authorized Mazda Dealer, change your
tire and complete ID signal code
registration.
When having tires changed at an
Authorized Mazda Dealer
When an Authorized Mazda Dealer,
changes your vehicle's tires, they will
complete the tire pressure sensor ID signal
code registration.

When changing tires yourself
If you or someone else changes tires, you
or someone else can also undertake the
steps for the TPMS to complete the ID
signal code registration.
1. After tires have been changed, switch the ignition ON, th en back to ACC or
OFF.
2. Wait for about 15 minutes.
3. After about 15 minutes, drive the
vehicle at a speed of at least 25 km/h
(16 mph) for 10 minutes and the tire
pressure sensor ID signal code will be
registered automatically.
NOTE
If the vehicle is driven within about 15
minutes of changing tires, the tire pressure
monitoring system warn ing light will flash
because the sensor ID signal code would
not have been registered. If this happens,
park the vehicle for about 15 minutes,
after which the sensor ID signal code will
register upon driving the vehicle for 10
minutes.
Replacing tires and wheels
CAUTION
 When replacing/repairing the tires or
wheels or both, have the work done by
an Authorized Mazda Dealer, or the tire
pressure sensors may be damaged.
 The wheels equipped on your Mazda are
specially designed for installation of the
tire pressure sensors. Do not use
non-genuine wheels, otherwise it may
not be possible to inst all the tire pressure
sensors.
Be sure to have the tire pressure sensors
installed whenever tires or wheels are
replaced.
When having a tire or wheel or both
replaced, the following types of tire
pressure sensor installations are possible.
The tire pressure sensor is removed
from the old wheel an d installed to the
new one.
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The same tire pressure sensor is used
with the same wheel. Only the tire is
replaced.
A new tire pressure sensor is installed to
a new wheel.
NOTE
The tire pressure sensor ID signal code
must be registered when a new tire
pressure sensor is purchased. For
purchase of a tire pressure sensor and
registration of the tire pressure sensor
ID signal code, consult an Authorized
Mazda Dealer.
When reinstalling a previously removed
tire pressure sensor to a wheel, replace
the grommet (seal between valve body/
sensor and wheel) for the tire pressure
sensor.
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