Description - Honda Acura NSX 1991 Service Manual

Description

The SRS is a safety device which, when used in conjunction with the seat belt, is designed to protect the driver by
operating only when the car receives a frontal impact exceeding a certain set limit.
The system is composed of left and right dash sensors, the SRS control unit (including the cowl sensor), the cable reel
and airbag assembly.
OPERATION:
As shown in the diagram below, the left and right dash sensors are connected in parallel. The parallel set of sensors are
connected in series by the airbag inflator circuit and the car battery. In addition, a backup power unit is connected in
parallel with the car battery. The backup power unit and the cowl sensor are located inside the SRS control unit.
The SRS operational sequence is as follows:
(2) Electrical energy is supplied to the airbag inflator by the battery, or the backup power unit if the battery voltage is
too low.
At least the cowl and one dash sensor must be activated simultaneously for at least 0.002 seconds in order for the airbag
to be deployed.
Self-diagnosis system
A self-diagnosis circuit is built into the SRS control unit; when the ignition switch is turned ON, the SRS light comes on
and goes out after about 6 seconds if the system is operating normally. If the light does not come on, or does not go out
after 6 seconds, or if it comes on while driving, this indicates an abnormality in the system. It must be inspected and
repaired as soon as possible.
DASH SENSOR (R)
\
DASH SENSOR IL)
I
CABLE REEL
SRS UNIT
SRS UNIT
\
ASSEMBLY
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