Mitsubishi MOTORS Lancer Evolution VIII 2003, Technical Information Manual

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SYSTEM OPERATION
SUPPLEMENTAL RESTRAINT SYSTEM (SRS) 52B-8
FRONT IMPACT SENSOR
CAUTION
Never disassemble the front impact sensor.
The front impact sensor is installed in the radiator support
panel. In a collision, the contact in the front impact sensor turns
ON and an output signal is send to the SRS-ECU. A resistor is
connected to the front impact sensor in parallel with the contact
for fault diagnosis.
SEAT BELT WITH PRE-TENSIONER
CAUTION
Never disassemble the seat belt with pre-ten-
sioner.
The seatbelt incorporating the pretensioner automat-
ically winds the seatbelt upon front impact to reduce
forward shifting of the passenger.
The seat belt pre-tensioner is built into the driver's
and passenger's front seat belt retractor.
Upon front impact the pretensioner ignites the gas
generator and emits gas with the SRS-ECU signal
when the front impact sensor, attached to the front of
the body, detects an impact that exceeds the permis-
sible limit. The gas pressure shifts the ball in the pipe
and the balls comes in contact with the protrusion of
the ring gear, The ball is inserted in the ring gear and
then interlocked with the pinion. The ring gear rota-
tion forces the pinion to turn the spool toward the belt
wind direction to wind the webbing.
AC206958AC
SENSOR INTERNAL CIRCUIT
AC101663AE
GAS GENERANT
SPOOL
PINION
RING GEAR
PIPE
BALL