Jaguar XJ (2008 year). Manual - part 18

 

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Jaguar XJ (2008 year). Manual - part 18

 

 

73

Occupant Protection

R

Air bag deployment

To do their life-saving job, air bags must 
inflate rapidly and with considerable 
force. There is therefore a risk of death or 
serious injuries such as fractures, facial 
and eye injuries or internal injuries, 
particularly to occupants who are not 
properly restrained by seat belts or sitting 
correctly when the air bag deploys.

The risk of injury from a deploying air bag 
is greatest close to the trim covering the 
air bag.

The whole sequence of events from 
sensing the impact to full inflation of the 
bag takes place in a fraction of a second.

The noise and gas associated with the 
deployment of the air bags is not injurious 
to health.

After air bag deployment, it is normal to 
notice a smoke-like, powdery residue or 
smell the burnt propellant. This may 
consist of cornstarch, talcum powder or 
sodium compounds that result from the 
combustion process that inflates the air 
bag.

Small amounts of other chemicals may be 
present which may irritate the skin and 
eyes, but none of the residue is toxic.

While the system is designed to help 
reduce serious injuries, it may also cause 
minor burns, abrasions, swelling or 
temporary hearing loss.

!

WARNING:

Safety experts recommend a minimum 
distance of at least 
254 mm (10 inches) between an 
occupant's chest and a front air bag.

!

WARNING:

No objects whatsoever should be 
attached to the centre cover of the 
steering wheel, the passenger facia 
panel, the sides of the front seats or the 
interior trim immediately above the 
door openings. Do not put anything on 
or over the air bag inflation area. 
Placing objects on or over the air bag 
inflation area may cause those objects 
to be propelled by the air bag into your 
face and torso causing serious injury.

!

WARNING:

Do not try to put an adult seat belt 
around two children.

!

WARNING:

Children 12 years old and younger can 
be killed or seriously injured by the air 
bag. The rear seat is the safest place 
for children.

!

WARNING:

Several air bag system components 
get hot after inflation. Do not touch 
them after they have deployed.

!

WARNING:

If an air bag is inflated, the air bag will 
not function again and must be 
renewed immediately. If a new air bag 
is not fitted, the unrepaired area will 
increase the risk of injury in a collision.

Occupant Protection

74

L

Air bag deployment effects

!

WARNING:

When an air bag inflates a fine powder 
is released. This is normal, and not an 
indication of a malfunction. However, 
the powder may cause irritation to the 
skin, and should be throughly flushed 
from eyes, and any cuts or abrasions.

!

WARNING:

After inflation some air bag 
components are at high temperatures. 
To prevent injury, do no touch the air 
bag components until they have 
cooled.

!

WARNING:

In order to react with sufficient speed, 
air bags are deployed by an explosive 
charge. Consequently air bag 
deployment is accompanied by a very 
loud noise which may cause 
discomfort and temporary loss of 
hearing.

Front protection

With a front impact of sufficient force, the 
restraints system will trigger the front air 
bag(s) and seat belt pretensioners, which 
immediately tighten the seat belts.

For front occupants, the seat belt then 
slackens with increasing chest load, 
allowing the head and chest to more 
gradually come into contact with the 
inflated air bag. The air bag absorbs the 
remaining energy of the impact and then 
deflates rapidly via vent holes.

Front air bags are designed to inflate in 
frontal and near-frontal collisions, not low 
speed impacts, roll-over, side impact or 
rear impact.

JAG0633

75

Occupant Protection

R

Side protection

The side protection system utilizes four air 
bags: Two mounted in the front seats, and 
two curtain air bags located just above 
the front and rear door openings, under 
the headlining trim.

When the seat mounted thorax and pelvis 
air bag inflates upon a vehicle side 
impact, it breaks through the seat bolster 
stitching, protecting the side of the rib 
cage and pelvis of the driver or front seat 
passenger.

When the curtain air bag inflates upon a 
vehicle side impact, it breaks through the 
headlining and deploys downwards, 
giving head protection to the front and 
rear seat occupants on the impact side.

The curtain air bag on the front passenger 
side is always deployed in a side impact 
even if the front passenger air bags are 
de-activated. This is to maintain 
protection for a rear occupant.

Seat mounted thorax and curtain air bags 
are designed to inflate in a side impact 
collision, not roll-over, rear impact, frontal 
or near-frontal collisions, unless the 
collision causes sufficient lateral 
deceleration.

The air bags, in combination with the seat 
belts, can help reduce the risk of severe 
injuries in the event of a significant side 
impact collision.

Whiplash protection

Both front seats are equipped with Active 
Head Restraints (AHR) which reduce the 
risk of neck and spinal injury (whiplash) in 
the event of a rear impact.
When activated, the head restraint moves 
upwards and forwards, cushioning the 
occupants’ head.

After activation, the whiplash protection 
mechanism automatically resets and 
does not require to be replaced.

JAG0813

Occupant Protection

76

L

!

WARNING:

For optimum protection, the driver and 
passenger should sit in the centre of 
the seat with the head as close as 
possible to the head restraint.

!

WARNING:

Adjust the head restraint so that it is 
just behind your head and never behind 
your neck.

!

WARNING:

Do not wedge objects (e.g. luggage) 
between the front seat backrest and 
the rear seat cushion.

!

WARNING:

After a rear collision, the front seats 
must be inspected by a Jaguar Dealer 
even where there is no apparent 
damage or change to the seat.

!

WARNING:

Do not attempt to service or tamper 
with the seat recliner mechanism.

Occupancy sensing

The front passenger seat is monitored by 
ultra-sonic sensors (shown above) and a 
seat weight sensor to determine the 
presence, weight and position of the front 
passenger. In certain conditions, e.g. 
where no passenger is present, the 
appropriate air bags will be de-activated. 
In a collision these air bags would not be 
deployed.

The occupancy sensor operates as 
follows:

Passenger 
occupancy 
status

Passenger 
air bag 
status

Indicator 
lamp 
active

Completely 
empty

Deactivated

No*

Low weight 
occupant/ 
object

Deactivated

Yes

Heavy 
occupant/ 
object

Activated

No

Passenger 
head too 
close to air 
bag door

Deactivated

Yes

JAG0635

 

 

 

 

 

 

 

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