Impact Sensor: Description and Operation

Impact Sensors:

Airbag/SRS System Schematic:

1. Driver-side Airbag Module
2. Cable Reel Cassette
3. Passenger-side Airbag Module
4. Diagnostic Module
5. LH Impact Sensor
6. RH Impact Sensor
7. Ground
8. Rear Safing Sensor
9. Cabin Harness Connector


The three impact sensor devices determine when airbag firing is necessary by detecting crash conditions according to direction of travel and force of movement. An impact of sufficient force in a forward direction will close contacts in either one or both of the front impact sensors, left and right. When either (or both) of the front sensors contacts are closed then the impact force must be sufficient to close the safing sensor contacts also, before airbag firing can commence. The front impact sensors are mounted between each headlamp mounting bracket and hood hinge mounting (Fig. 2), the safing sensor is mounted on the right-hand side footwell at the base of the "A" post.