MAZDA MODEL 3 HATCHBACK 2009 (in English) Repair Manual

Black plate (61,1)
Driver and front passenger seat belt buckle switches (page 2-48)
Driver seat slide position sensor
Front seats
Essential Safety Equipment
SRS Air Bags
2-47
Mazda3_8Z87-EA-08F_Edition1 Page61
Monday, May 19 2008 9:56 AM
Form No.8Z87-EA-08F

Black plate (62,1)
How the Air Bags Work
qHow the Front Air Bags Work
When air bag crash sensors detect a frontal impact of greater than moderate force, an
electrical current is sent to the inflators.
Gases are produced to inflate the front air bags and after the inflation, the front air bags
quickly deflate.
The front air bags will function only once. After that, the front air bags will not work
again and must be replaced.
Only an Authorized Mazda Dealer can replace the system components.
The front, dual stage air bags control air bag inflation in two energy stages. During an
impact of moderate severity the front air bags deploy with lesser energy, whereas during
more severe impacts, they deploy with more energy. Deployment of the front air bags may
differ between the driver and the front passenger depending on the driver seat position,
front passenger weight and front seat belt usage, all of which provide data from each sensor
to the air bag system.
The front air bags will deploy only
in a frontal or frontal offset impact.
Driver seat slide position sensor
Your vehicle is equipped with a driver seat slide position sensor as a part of the
supplemental restraint system. The sensor is located under the driver seat. The sensor
determines whether the driver seat is fore or aft of a reference position and sends the seat
position to the diagnostic module (SAS unit). The SAS unit is also designed to control the
deployment of the driver air bag depending on how close the driver seat is to the steering
wheel.
The air bag/front seat belt pretensioner system warning light flashes if the sensor has a
possible malfunction (page 2-57).
2-48
Essential Safety Equipment
SRS Air Bags
Mazda3_8Z87-EA-08F_Edition1 Page62
Monday, May 19 2008 9:56 AM
Form No.8Z87-EA-08F

Black plate (63,1)
Front passenger seat weight sensors
Your vehicle is equipped with a front passenger seat weight sensors as a part of the
supplemental restraint system. (page 2-35). These sensors are located under both of the
front passenger seat rails. These sensors determine the total seated weight on the front
passenger seat. The SAS unit is designed to prevent the front passenger front and side air
bags and seat belt pretensioner system from deploying if the total seated weight is less than
approximately 30 kg (66 lbs).
To reduce the chance of injuries caused by deployment of the front passenger air bag, the
system deactivates the front passenger front and side air bags and also the seat belt
pretensioner system when:
lThere is no passenger in the front passenger seat. (The front passenger air bag
deactivation indicator light does not illuminate.)
lThe total seated weight on the front passenger seat is less than approximately 30 kg (66
lbs). (The front passenger air bag deactivation indicator light illuminates.)
This system shuts off the front passenger front and side air bags and seat belt pretensioner
system, so make sure the front passenger air bag deactivation indicator light illuminates
according to the following table.
The air bag/front seat belt pretensioner system warning light flashes and the front
passenger air bag deactivation indicator light illuminates if the sensors have a possible
malfunction. If this happens, the front passenger front and side air bags and seat belt
pretensioner system will not deploy.
Front passenger air bag deactivation indicator light
This indicator light illuminates to remind you that the front passenger front and side air
bags and seat belt pretensioner will not deploy during a collision.
With seat warmer
Without seat warmer
Essential Safety Equipment
SRS Air Bags
2-49
Mazda3_8Z87-EA-08F_Edition1 Page63
Monday, May 19 2008 9:56 AM
Form No.8Z87-EA-08F

Black plate (64,1)
If the front passenger weight sensors are working properly, the indicator light illuminates
when the ignition switch is turned to the ON position. After a specified period of time it
goes out.
The front passenger air bag deactivation indicator light illuminates or is off under the following conditions:Total seated weight on the front passenger seat Front passenger air bag
deactivation indicator light Front passenger front and
side air bags Front passenger seat
belt pretensioner system
Empty (Not occupied)
*OFF Deactivated Deactivated
Less than approx. 30 kg
(66 lbs) ON
Deactivated Deactivated
Approx. 42 kg (93 lbs) or
more OFF
ReadyReady
* If the front passenger seat belt is buckled, the front passenger air bag deactivation indicator light illuminates, however this does not indicate a malfunction.
Curtain air bag is always ready to inflate and is not deactivated like the passenger front and side air bag.
If the front passenger air bag deactivation indicator light does not illuminate when the
ignition switch is turned to the ON position and does not illuminate as indicated in the
above chart, do not allow a child to sit in the front passenger seat; contact the Authorized
Mazda Dealer as soon as possible. The system may not work properly in an accident.
2-50
Essential Safety Equipment
SRS Air Bags
Mazda3_8Z87-EA-08F_Edition1 Page64
Monday, May 19 2008 9:56 AM
Form No.8Z87-EA-08F

Black plate (65,1)
WARNING
Do not decrease the total seated weight on the front passenger seat:When an adult or large child sits on the front passenger seat, decreasing the total
seated weight on the front passenger seat from the total seated weight of
approximately 42 kg (93 lbs) required for air bag deployment is dangerous. The front
passenger seat weight sensors will detect the reduced total seated weight condition
and the front passenger front and side air bags and seat belt pretensioner system
will not deploy during an accident. The front passenger will not have the
supplementary protection of the air bag, which could result in serious injury.
Decreasing the total seated weight on the front passenger seat from the total seated
weight of approximately 42 kg (93 lbs) could result in an air bag not deploying under
the following conditions, for example:
ØA rear passenger pushes up on the front passenger seat with their feet.
Ø Luggage or other items placed under the front passenger seat or between the
front passenger seat and driver seat that push up the front passenger seat
bottom.
Ø The front passenger seat occupant sits in a manner that does not place the entire
weight of the occupant on the seat such as by sitting too close to the door,
grasping the assist grip or the rim of the moonroof and sitting with the seatback
reclined too far.
Ø Any accessories which might decrease the total seated weight on the front
passenger seat are attached to the front passenger seat.
The front passenger front and side air bags and seat belt pretensioner systems will
deactivate if the total seated weight on the front passenger seat is close to 30 kg (66
lbs) and they will reactivate before the weight exceeds 42 kg (93 lbs).
Essential Safety Equipment
SRS Air Bags
2-51
Mazda3_8Z87-EA-08F_Edition1 Page65
Monday, May 19 2008 9:56 AM
Form No.8Z87-EA-08F

Black plate (66,1)
Do not increase the total seated weight on the front passenger seat:When an infant or small child sits on the front passenger seat, increasing the total
seated weight on the front passenger seat from the total seated weight of
approximately 30 kg (66 lbs) is dangerous. The front passenger seat weight sensors
will detect the increased total seated weight, which could result in the unexpected
deployment of the front passenger front and side air bags and seat belt pretensioner
system in an accident and may cause serious injury. Increasing the total seated
weight on the front passenger seat beyond the total seated weight of approximately
30 kg (66 lbs) could result in the front passenger front and side air bags and seat
belt pretensioner system deployment in an accident under the following conditions,
for example:
ØLuggage or other items are placed on the seat with the child in the child-restraint
system.
Ø A rear passenger or luggage push or pull down on the front passenger seatback.
Ø A rear passenger steps on the front passenger seat rails with their feet.
Ø Luggage or other items are placed on the seatback or hung on the head restraint.
Ø The seat is washed.
Ø Liquids are spilled on the seat.
Ø The front passenger seat is moved backward, pushing into luggage or other items
placed behind it.
Ø The front passenger seatback contacts the rear seat.
Ø Luggage or other items are placed between the front passenger seat and driver
seat.
Ø Any accessories which might increase the total seated weight on the front
passenger seat are attached to the front passenger seat.
The front passenger front and side air bags and seat belt pretensioner systems will
deactivate if the total seated weight on the front passenger seat is less than
approximately 30 kg (66 lbs) and they will reactivate when the weight exceeds
approximately 42 kg (93 lbs).
CAUTION
Ø To assure proper deployment of the front air bag and to prevent damage to the
sensors in the front seat bottoms:
ØDo not place sharp objects on the front seat bottoms or leave heavy luggage on
them.
ØDo not spill any liquids on the front seats or under the front seats.
Ø To allow the sensors to function properly, always perform the following:
ØAdjust the front seats as far back as possible and always sit upright against the
seatbacks with seat belts worn properly.
ØIf you place your child on the front passenger seat, secure the child-restraint
system properly and slide the front passenger seat as far back as possible (page
2-35).
2-52
Essential Safety Equipment
SRS Air Bags
Mazda3_8Z87-EA-08F_Edition1 Page66
Monday, May 19 2008 9:56 AM
Form No.8Z87-EA-08F

Black plate (67,1)
NOTElThe system requires about 10 seconds to alternate between turning the front passenger front and
side air bags and seat belt pretensioner system on or off.
lThe front passenger air bag deactivation indicator light may illuminate repeatedly if luggage or
other items are put on the front passenger seat, or if the temperature of the vehicle's interior
changes suddenly.
lThe front passenger air bag deactivation indicator light may illuminate for 10 seconds if the total
seated weight on the front passenger seat changes.
lIf the front passenger air bag deactivation indicator light does not illuminate after installing a
child-restraint system on the front passenger seat, install the child-restraint system on the rear
seat and consult an Authorized Mazda Dealer as soon as possible.
Driver and front passenger buckle switches
The buckle switches on the front seat belts detect whether or not the front seat belts are
securely fastened and further control the deployment of the air bags.
qHow the Side and Curtain Air Bags Workí
When air bag crash sensors detect a side impact of greater than moderate force, an
electrical current is sent to the inflators.
Gases are produced to inflate the side and curtain air bags and after the inflation, the side
and curtain air bags quickly deflate. However, the side air bag system for the front
passenger is designed to only deploy in accordance with the total seated weight on the front
passenger seat, however the curtains are not deactivated.
The side and curtain air bags will function only once. After that, the side and curtain air
bags will not work again and must be replaced. Only an Authorized Mazda Dealer can
replace the systems.
The side and curtain air bags will deploy only on the
side the vehicle receives the force of the impact.
Essential Safety Equipment
SRS Air Bags
2-53íSome models.
Mazda3_8Z87-EA-08F_Edition1 Page67
Monday, May 19 2008 9:56 AM
Form No.8Z87-EA-08F

Black plate (68,1)
qAir Bag Activation/Deactivation
NOTE
If the front passenger seat weight sensors detect a total seated weight on the front passenger seat is
less than approximately 42 kg (93 lb), the front passenger front and side air bags and seat belt
pretensioner may not deploy (page 2-48), but the curtain air bags may deploy.
Front air bag activation
The front air bags will inflate if the
severity of impact is above the designed
threshold level.
lHitting a solid wall straight on at
greater than about 22 km/h (14 mph).
lHitting a curb, pavement edge or hard
object.
lLanding hard or the vehicle falling.
lFrontal impact within about a 30
degree range from head-on to the
vehicle.
lDriving into a big hole or hitting the far
side of a hole.
Limitations to front air bag activation
Depending on the severity of impact, the
front air bags may not inflate in the
following cases:
lImpacts involving trees or poles cause
severe cosmetic damage but may not
have enough stopping force to activate
the air bag.
2-54
Essential Safety Equipment
SRS Air Bags
Mazda3_8Z87-EA-08F_Edition1 Page68
Monday, May 19 2008 9:56 AM
Form No.8Z87-EA-08F

Black plate (69,1)
lFrontal offset impact to the vehicle
may not provide the stopping force
necessary for air bag deployment.
lRear-ending or running under a truck's
tail gate may not provide the stopping
force necessary for air bag deployment.
Non-activation of front air bags
Front air bags will not normally inflate in
the following cases:
lCollision from the rear.
lImpact to the side, but it may deploy
the side and curtain air bags.
lVehicle roll-over, may deploy the side
and curtain air bags but not the front air
bags.
Side and curtain air bag activationí
The severity of impact above the designed
threshold level to one side of the vehicle
(driver or passenger side areas) will cause
the side and curtain air bags on that side
to inflate, but it will not normally deploy
the front air bags.
Limitations to side and curtain air bag
activationí
Depending on the severity of impact, the
side and curtain air bags may not inflate in
the following cases:
lFrontal offset impact may not provide
enough side impact to deploy the side
and curtain air bags.
Essential Safety Equipment
SRS Air Bags
2-55íSome models.
Mazda3_8Z87-EA-08F_Edition1 Page69
Monday, May 19 2008 9:56 AM
Form No.8Z87-EA-08F

Black plate (70,1)
lSide impacts involving trees or poles
can cause severe cosmetic damage but
may not have enough impact force to
activate the side and curtain air bags.
lVehicle roll-over may not provide
enough side force to deploy the side
and curtain air bags.
lSide impacts with two-wheeled
vehicles may not provide enough force
to deploy the side and curtain air bags.
Non-activation of side and curtain air
bagí
The side and curtain air bags will not
normally inflate in the following cases:
lCollision from the rear.
lCollision from the front, but it may
deploy the front air bags.
qConstant Monitoring
The following components of the air bag
systems are monitored by a diagnostic
system:
lSAS unitlFront air bag sensorlAir bag moduleslSide crash sensorsí
lAir bag/Front seat belt pretensioner
system warning light
lFront seat belt pretensionerslFront passenger air bag deactivation
indicator light
lRelated wiringlDriver seat slide position sensorlFront passenger seat weight sensorslDriver and front passenger seat belt
buckle switches
2-56
Essential Safety Equipment
íSome models.
SRS Air Bags
Mazda3_8Z87-EA-08F_Edition1 Page70
Monday, May 19 2008 9:56 AM
Form No.8Z87-EA-08F