2011 Seat Leon 5D sensor

29
Seat belts
Seat belt tensioners
Function of the seat belt tensioner
During a frontal collision, the seat belts on the front seats
are retracted automatically. The seat belts for the front occupants are equipped with belt tensioners.
Sensors will only trigger the belt tensioners during severe head-on, lateral
and rear collisions, and only if the seat belt is actually being worn. This re-
tracts and tightens the seat belts, reducing the forward motion of the occu-
pants.
The seat belt tensioner can be triggered only once.
The seat belt tensioners will not be triggered in the event of a light frontal,
side or rear collision, if the vehicle overturns or in situations where no large
forces act on the front, side or rear of the vehicle.
Note
● If the seat belt tensioners are triggered, a fine dust is produced. This is
normal and it is not an indication of fire in the vehicle.
● The relevant safety requirements must be observed when the vehicle or
components of the system are scrapped. Specialised workshops are famili-
ar with these regulations, which are also available to you. 
Service and disposal of belt tensioners
The belt tensioners are components of the seat belts that are installed in
the seats of your vehicle. If you work on the belt tensioners or remove and
install parts of the system when performing other repair work, the seat belt
may be damaged. The consequence may be that, in the event of an acci-
dent, the belt tensioners function incorrectly or not at all. So that the effectiveness of the seat belt tensioner is not reduced and that
removed parts do not cause any injuries or environmental pollution, regula-
tions, which are known to the specialised workshops, must be observed.
WARNING
● Improper use or repairs not carried out by qualified mechanics in-
crease the risk of severe or fatal injuries. The belt tensioners may fail to
trigger or may trigger in the wrong circumstances.
● Never attempt to repair, adjust, remove or install parts of the belt ten-
sioners or seat belts.
● The seat belt tensioner, seat belt and automatic retractor cannot be
repaired.
● Any work on the belt tensioners and seat belts, including the removal
and refitting of system parts in conjunction with other repair work, must
be performed by a specialised workshop only.
● The belt tensioners will only provide protection for one accident and
must be changed if they have been activated.

Safety FirstOperating InstructionsPractical TipsTechnical Specifications

38Airbag system
Side airbags*
Description of side airbags
The airbag system is not a substitute for the seat belts.
Fig. 21 Side airbag in
driver seat
The side airbags are located in the backrest cushions of the driver seat
⇒ fig. 21 and the front passenger seat as well as in the rear seats. The loca- tions are identified by the text “AIRBAG” in the upper region of the backr-
ests.
Together with the seat belts, the side airbag system gives the front seat oc-
cupants additional protection for the upper body in the event of a severe
side collision ⇒ page 40, Safety notes on the operation of the side airbagsystem.
In a side collision, the side airbags reduce the risk of injury to passengers
on the front seats to the areas of the body facing the impact. In addition to
their normal function of protecting the occupants in a collision, the seat
belts also hold the passengers on the front seats and the outer rear seats in
a position where the side airbags can provide maximum protection. The airbag system is not a substitute for seat belts, but it is an integral part
of the vehicle's overall passive safety system. Please bear in mind that the
airbag system can only work effectively when the occupants are wearing
their seat belts. Therefore, it is most important to wear the seat belts at all
times, not only because this is required by law in most countries, but also
for your safety
⇒ page 19, Brief introduction.
The side airbag system will not be triggered if:
● the ignition is switched off
● there is a minor side collision
● there is a frontal collision
● there is a rear-end collision
● the vehicle turns over
The main parts of the airbag system are:
● an electronic control and monitoring system (control unit)
● the side airbags in the sides of the backrests of the front and rear seats
● a warning lamp  on the instrument panel ⇒ page 32
The airbag system operation is monitored electronically. The airbag warning
lamp will light up for approx. 4 seconds every time the ignition is switched
on (self-diagnosis).
WARNING
● In a side-on collision the side airbags will not work if the sensors do
not correctly measure the pressure increase on the interior of the doors,
due to air escaping through the areas with holes or openings in the door
panel.
● Never drive the vehicle if the interior panels have been removed.
● Never drive if the interior door panels have been removed or if the
panels have not been correctly fitted. 

40Airbag system
The special design of the airbag allows the controlled escape of the propel-
lant gas when an occupant puts pressure on the bag. Thus, the head and
chest are surrounded and protected by the airbag. 
Safety notes on the operation of the side airbag system
If airbags are used correctly, they can considerably reduce
the risk of injury in side impact collisions.
WARNING
● If you do not wear a seat belt, if you lean forward, or are not seated
correctly while the vehicle is in motion, you are at a greater risk of injury
if the side airbag system is triggered in an accident.
● In order for the side airbags to provide their maximum protection, the
prescribed sitting position must always be maintained with seat belts
fastened while travelling.
● Occupants of the outer seats must never carry any objects or pets in
the deployment space between them and the airbags, or allow children
or other passengers to travel in this position. It is also important not to
attach any accessories (such as cup holders) to the doors. This would im-
pair the protection offered by the side airbags.
● The built-in coat hooks should be used only for lightweight clothing.
Do not leave any heavy or sharp-edged objects in the pockets.
● Great forces, such as hard blows or kicks, must not be exerted upon
the backrest bolster because the system may be damaged. In this case,
the side airbags would not be triggered.
WARNING (Continued)
● Under no circumstances should protective covers be fitted over seats
with side airbags unless the covers have been approved for use in your
vehicle. Because the airbag is triggered from the side of the backrest, the
use of non-approved seat covers would obstruct the side airbag, serious-
ly reducing the airbag's effectiveness ⇒ page 208, Accessories, parts re-
placement and modifications.
● Any damage to the original seat upholstery or around the seams of
the side airbag units must be repaired immediately by a specialised
workshop.
● The airbags provide protection for just one accident; replace them
once they have deployed.
● When children assume an incorrect sitting position, they expose
themselves to an increased risk of injury in the event of an accident. This
is particularly the case if the child is travelling on the front passenger
seat and the airbag system is triggered in an accident; this could have
critical consequences including serious injury or death ⇒ page 46,
Child safety.
● Any work on the side airbag system or removal and installation of the
airbag components for other repairs (such as removal of the front seat)
should only be performed by a specialised workshop. Otherwise, faults
may occur during the airbag system operation.
● Do not attempt to modify components of the airbag system in any
way.
● The side and head airbags are managed through sensors located in
the interior of the front doors. To ensure the correct functioning of the
side and head airbags neither the doors nor the door panels should be
modified in any way (e.g. fitting loudspeakers). If the front door is dam-
aged, the airbag system may not work correctly. All work carried out on
the front door must be made in a specialised workshop.


43
Airbag system
WARNING (Continued)
not been expressly approved for use in your vehicle may not be attached
to the side windows ⇒ page 208, Accessories, parts replacement and
modifications.
● The built-in coat hooks should be used only for lightweight clothing.
Do not leave any heavy or sharp-edged objects in the pockets. Please, do
not hang the clothes on coat hangers.
● The airbags provide protection for just one accident; replace them
once they have deployed.
● Any work on the curtain airbag system or removal and installation of
the airbag components for other repairs (such as removal of the roof lin-
ing) should only be performed by a specialised workshop. Otherwise,
faults may occur during the airbag system operation.
● Do not attempt to modify components of the airbag system in any
way.
● The side and head airbags are managed through sensors located in
the interior of the front doors. To ensure the correct functioning of the
side and head airbags neither the doors nor the door panels should be
modified in any way (e.g. fitting loudspeakers). If the front door is dam-
aged, the airbag system may not work correctly. All work carried out on
the front door must be made in a specialised workshop.

Safety FirstOperating InstructionsPractical TipsTechnical Specifications

78Cockpit
ItemSymbolMeaning of warning and indicator
lampsFurther infor-mation
1Fuel level / reserve⇒ page 81
2Coolant level / coolant temperature⇒ page 82
3Rear fog light switched on⇒ page 82
4
Turn signals in operation⇒ page 83
5Engine fault (petrol engine)⇒ page 83
Glow plug system for diesel engine⇒ page 83
6Main beam switched on⇒ page 83
7Soot accumulation in the diesel engine
particulate filter⇒ page 83
8ABS system fault⇒ page 84
9Windscreen washer fluid level⇒ page 84
10Alternator fault⇒ page 85
11Fasten seat belts!⇒ page 19
12Brake pad worn⇒ page 85
13Tyre pressure⇒ page 85
ItemSymbolMeaning of warning and indicator lampsFurther infor-mation
14Airbag or belt tensioner system fault or
airbag disabled⇒ page 29
⇒ page 32
15Bulb defective⇒ page 87
16Brake fluid required or
brake system fault⇒ page 86
17
Red:
Engine oil pressure
⇒ page 87Yellow:
If flashing: engine oil sensor faulty
If it remains lit: insufficient engine oil
18Handbrake on⇒ page 173
19Cruise speed activated (Cruise control)⇒ page 88
20Door open indicator⇒ page 88
21If it stays lit: ASR (TCS) deactivated⇒ page 89
⇒ page 89
⇒ page 158
22Electromechanical steering⇒ page 88
23Fault in the emission control system⇒ page 88
24If flashing: the Electronic Stability Con-
trol ESC (ESP) or the ASR (TCS) is work-
ing
If it remains lit: ESC (ESP) or ASR (TCS)
faulty⇒ page 89
⇒ page 89
⇒ page 158

25Selector lever lock (automatic gearbox)⇒ page 90 

85
Cockpit
The following message is shown on the instrument panel display* 1)
: REFILL
WINDSCREEN WASHER FLUID . 
Alternator 
This warning lamp signals a fault in the alternator.
The warning lamp  lights up when the ignition is switched on. It should
go out when the engine has started running.
If the warning lamp  lights up while driving, the alternator is no longer
charging the battery. You should immediately drive to the nearest special-
ised workshop.
You should avoid using electrical equipment that is not absolutely necessa-
ry because this will drain the battery. 
Worn brake pads 
If the  symbol lights up, have the front brake pads (and, for safety rea-
sons, the rear pads as well) inspected by a specialised workshop. Tyre pressure 
The tyre pressure control system controls the tyre speed and
the frequency spectrum of each tyre.
Fig. 50 Centre console:
tyre monitor system but-
ton
The tyre warning lamp 2)
compares wheel revolutions and with this informa-
tion, the diameter of each wheel using the ESC (ESP) sensors. If the diame-
ter of a wheel changes, the tyre warning lamp  lights up. The wheel diam-
eter changes when:
● Tyre pressure is insufficient.
● The tyre structure is damaged.
● The vehicle is unbalanced because of a load.
● The wheels of one axle are under more pressure (for example, driving
with a trailer or on extreme slopes).
● The vehicle is fitted with snow chains. 
1)
Depending on the version of the model.
2) Depending on the model version
Safety FirstOperating InstructionsPractical TipsTechnical Specifications

87
Cockpit
WARNING
● Before opening the bonnet, read and observe the warnings on
⇒ page 217.
● If the brake warning lamp does not go out, or if it lights up when driv-
ing, the brake fluid level ⇒ page 229, Brake fluid in the reservoir is too
low. Risk of accident. Stop the vehicle and do not drive on. Obtain techni-
cal assistance.
● If the brake warning lamp  lights up together with the ABS warning
lamp , the control function of the ABS could be out of action. This could
cause the rear wheels to lock quickly when you brake. This could cause
the rear to break away. Risk of skidding. Stop the vehicle and seek tech-
nical assistance.

Handbrake 
This lamp lights up when the handbrake is applied. If you drive faster than 6 km/h with the handbrake on, the following mes-
sage will appear on the instrument panel display 1)
: HANDBRAKE ON. You will
also hear an acoustic warning signal ⇒ page 173. 
Bulb defect 
The warning lamp lights up when a bulb in the vehicle's ex-
terior lighting is defective.
The warning lamp  lights up when a bulb in the vehicle's exterior lighting
(e.g. left-hand main beam) is defective. The instrument panel displays the following message
1)
: LEFT FULL BEAM
FAULTY. 
Engine oil pressure 
If this warning lamp is red it indicates that the engine oil
pressure is too low.
If this warning symbol starts to flash, and is accompanied by three audible
warnings, switch off the engine and check the oil level. If necessary, add
more oil ⇒ page 220.
The instrument panel displays the following message 1)
: STOP ENGINE OIL
PRESSURE INSTRUCTION MANUAL .
If the symbol flashes although the oil level is correct, do not drive on. The
engine must not even run at idle speed. Obtain technical assistance.
Checking the oil level 
If the warning lamp is yellow  the engine oil level should be checked as
soon as possible. Top up the oil ⇒ page 222 at the next opportunity.
Oil level sensor faulty* 
If the  yellow warning lamp flashes, take the vehicle to a specialised
workshop to have the oil level sensor checked. Until then it is advisable to
check the oil level every time you refuel. 
1)
Depending on the version of the model.
Safety FirstOperating InstructionsPractical TipsTechnical Specifications

106Unlocking and locking
Anti-theft alarm system*
Description of anti-theft alarm system*
The anti-theft alarm triggers if unauthorised movements are
detected around the vehicle.
The anti-theft alarm makes it more difficult to break into the vehicle or steal
it. Audible and visible alarms are triggered if the vehicle is opened using
the key, or if unauthorised access to the vehicle is forced.
The anti-theft alarm system is automatically connected on locking the vehi-
cle. The system is then primed.
When does the system trigger an alarm?
The system triggers an alarm if the following unauthorised actions are car-
ried out when the vehicle is locked:
● Mechanical opening of the vehicle with the vehicle key
● Opening a door
● Opening the bonnet
● Opening the tailgate
● Switching on the ignition
● Movements in the vehicle interior
● Undue manipulation of the alarm
● Battery handling
The acoustic signals sound and the turn signals flash for approx. 30 sec-
onds. This may be repeated up to 10 times depending on the country.
Opening the doors mechanically (emergency opening)
If the remote control function fails, you will have to use the key to unlock the
vehicle. This is done as follows: ●
Unfold the key by pressing the button shown by the (arrow).
● Use the lock on the driver door to unlock the vehicle. The anti-theft
alarm system remains active, but an alarm is not triggered immediately.
● Switch on the ignition within 15 seconds. When the ignition is switched
on, the electronic immobiliser recognises a valid vehicle key and deacti-
vates the anti-theft alarm system. If you do not switch on the ignition within
15 seconds, the alarm is triggered.
Opening all the doors in manual mode
In vehicles without alarm, when opening the driver door manually all the
doors are opened.
How to switch the alarm off
When the vehicle is unlocked via the unlocking button of the remote control
or when the key is inserted in the ignition lock.
Note
● If, after the alarm goes off, another monitored area is accessed (e.g. the
tailgate is opened after a door has been opened), the alarm is triggered
again.
● Vehicle monitoring remains active even if the battery is disconnected or
not working for any reason.
● The alarm is triggered immediately if one of the battery cables is discon-
nected while the alarm system is active. 
Volumetric sensor*
Monitoring or control function incorporated in the anti-theft
alarm* which detects unauthorized vehicle entry by means
of ultrasound.
The system consists of 3 sensors, 2 emitters and a receptor. 