Mitsubishi Eclipse. Technical Information Manual (1994) - part 82

INTERIOR   Supplemental Restraint System (SRS)

CONSTRUCTION AND OPERATION

IMPACT SENSORS
There are 2 different types of sensors used; 2 front

built in the SRS diagnosis unit. The right and left

impact sensors and safing impact sensor. One front
impact sensor is provided in each of the right and

front impact sensors are connected in parallel.

left shield 

 and one safing impact sensor is

The front impact sensors are connected in series
with the safing impact sensor.

Safing impact
sensor (Incorporated
in SRS diagnostic unit)

Air bag
module
<Driver’s side>

Front impact

sensor (L.H.)

From

power supply 

<Passenger’s side>

Front impact

sensor (R.H.)

1 9 x 0 5 9 3

If a front-end collision causes either of the front

impact sensors and the safing impact sensor to
be simultaneously “ON”, the air bag will deploy.

They are constructed as shown below and contain
a G sensor each.
The front and safing impact sensors are essentially

identical in construction.

The G sensor consists of a moving contact which

is a roll spring wound around a roller, a fixed contact
positioned in its moving direction, consisting of a
base, a metallic case, etc. If an impact greater than

preset is applied in the direction of the arrow shown

in the illustration, the inertial force causes the roller

Front impact sensor

Safing impact sensor

Roller

Fixed

to rotate and move, so that contacts are brought
into the ON stage. To maintain a high measure
of G sensor reliability, the contacts have been gold
plated and the metallic case charged with an inactive
gas.

Each impact sensor contains a resistor connected
in parallel with the contacts for detection of a fault
in the wiring. The SRS diagnosis unit always sup-

plies a very small amount of current to the sensor
circuit to monitor a change in the circuit resistance.

Caution

Make sure that the impact sensors are never

disassembled.

Roller

Moving contact

Fixed contact

INTERIOR   Supplemental Restraint System (SRS)

Hinge portion

of pad cover

Inflator

AIR BAG MODULE

<Driver’s side>
The air bag module is an assembly part comprising of an
air bag, pad cover, inflator, and parts for securing them. It

is provided at the center of the steering wheel.

Caution
Make sure that the air bag is never disassembled.

Section 

A 

 

   Pad cover deploying direction

Air bag
The air bag is made of a nylon cloth with a rubber
coating inside. It is accommodated in the pad at
the center of the steering wheel together with the

inflator.

The air bag is inflated by the nitrogen gas from
the inflator. The load of the driver pressed against

Pad cover

The pad cover is made from urethane. When the
air bag deploys, the crease is broken, allowing the
air bag to move out and deploy with the hinge por-
tions as its fulcrums. The pad cover has a net, etc.

Groove portion

Pad cover

Groove 

‘Air bag

Inflator

Section B   B

the air bag by the impact causes the nitrogen gas
to escape through the two exhaust holes made on
the rear, and the deflation helps lessen the impact.

insert-molded except for the crease to prevent the
air bag from being broken as it deploys, and also

to prevent broken pieces from scattering around.

INTERIOR   

 Restraint System 

Inflator

The inflator consists of a squib, igniter, gas 
ants, diffuser screen, etc. contained in an aluminum
container. It is mounted in the air bag module hous-

ing.

The bottom of the inflator is provided with an electri-
cal connection to which an ignition current is sup-

plied. If current is supplied to the squib, a small

amount of explosive in the squib is burnt causing
the igniter to burn, and the resultant heat burns
the gas generants. Combustion of the generants

rapidly produces nitrogen gas which is forced
through the diffuser screen into the air bag. The
diffuser screen serves as a filter to remove cinders
and also helps cool down the gas temperature and
reduce the gas generation noise. A shorting pin
is provided in the connector portion of the squib.
Whenever the air bag module is removed, the short-
ing pin makes a short circuit across the terminals

to prevent flow of current caused by static electricity
to the squib.

Diffuser

Igniter

Gas 

To air bag

To air bag

 

Shorting clip

Diffuser screen

  Nitrogen gas

   Flame

INTERIOR   Supplemental Restraint System 

<Passenger’s side>
The air bag module consists of an air bag, module cover,
inflator, and parts for securing them. It is provided above the
glove box.

Caution
Make sure that the air bag is never disassembled.

Module cover

Air bag
The air bag, made of nylon cloth lined with rubber
coating, is housed together with the inflator, under
the module cover provided above the glove box.
The air bag is inflated with nitrogen gas generated
by the inflator. Then, as the front passenger hits

Module cover

The module cover has aluminum sheet and urethane
formed into a unit. It is normally closed by hard

rubber type locks on both the sides.

When the air bag is deployed, the hard rubber type

lock is broken, allowing the module cover to turn

the air bag, the gas is discharged from the two

exhaust holes, one on each side, deflating the air
bag to reduce the impact on the passenger.

on the hinge provided at the upper part, open upward
and let the air bag out to be inflated.