Impact Sensor - Description

OCCUPANT RESTRAINT

Remote or satellite impact sensors are mounted in various strategic locations of the vehicle. These sensors are mounted remotely from the impact sensor that is internal to the Occupant Restraint Controller (ORC). Sensors at the front of the vehicle provide an additional logic input for use by the Occupant Restraint Controller (ORC) to control the front airbags and the seat belt pretensioners. Sensors on each side of the vehicle provide an additional logic input for use by the ORC to control the side curtain airbags, seat airbags and the seat belt pretensioners. Two types of sensors are used in this vehicle. They are the acceleration-type and the pressure-type, which are described in further detail in the following paragraphs.

ACCELERATION TYPE





Remote or satellite acceleration-type impact sensors (1) are mounted in various locations in the vehicle. These sensors are mounted remotely from the impact sensor that is internal to the Occupant Restraint Controller (ORC). Sensors at the front of the vehicle provide an additional logic input for use by the ORC to control the front airbags and the seat belt pretensioners. Sensors on each side of the vehicle provide an additional logic input for use by the ORC to control the side curtain airbags, the seat belt pretensioners and the seat (also known as pelvic and thorax) airbags.

Although the front and side acceleration-type impact sensors are similar in appearance and construction, they may not be interchangeable. The front impact sensors may monitor acceleration forces on a different axis than those monitored by the side impact sensors. Each sensor is secured with a single screw to its mounting location. The front sensors are located on the back of each vertical support member of the headlamp mounting cross member between the cooling module and the front lamp unit. A side sensor is located near the base of each inner B-pillar and near the belt line of each C-pillar and concealed behind the interior trim.

Each sensor housing has an integral connector receptacle (3), an integral locator pin with two latch features (5), and an integral mounting hole with a metal sleeve (2) to provide crush protection. A cavity in the center of the molded plastic impact sensor housing contains the electronic circuitry of the sensor which includes an electronic communication chip and an electronic acceleration sensor. Potting material fills the cavity and a molded cover (4) is laser welded over the cavity to seal and protect the internal electronic circuitry and components.

The front impact sensors are each connected to the vehicle electrical system through dedicated take outs and connectors of the headlamp and dash wire harness, while the side impact sensors are connected through dedicated take outs and connectors of the body wire harness.

The acceleration-type impact sensors cannot be repaired or adjusted and, if damaged or ineffective, they must be replaced.

PRESSURE TYPE





Two pressure-type front door side impact sensors (2) are used on this vehicle, one each for the left and right sides of the vehicle. These sensors are mounted remotely from the impact sensor that is internal to the Occupant Restraint Controller (ORC). Each side sensor is secured with two screws and is sealed by a resilient gasket (1) to the front door hardware module carrier on the front door inner panel. The sensors are concealed behind the front door trim panel within the passenger compartment.

The right and left front door side impact sensors are identical in construction and calibration. The impact sensor housing has an integral connector receptacle (3), two integral mounting tabs, and an integral hood-like water shield (4). The water shield extends through a hole in the front door module carrier into the interior of the door cavity and protects the sensor orifice from contamination. A cavity in the center of the molded plastic impact sensor housing contains the electronic circuitry of the sensor, which includes an electronic communication chip and the pressure sensor.

The housing cavity is filled with a potting material to seal and protect the internal electronic circuitry and components. A label on the sensor has a directional arrow and the word down imprinted upon it to provide verification of the correct sensor orientation in the vehicle. The pressure-type side impact sensors are each connected to the vehicle electrical system through a dedicated take out and connector of the front door wire harness.

These pressure-type front door side impact sensors cannot be repaired or adjusted and, if damaged or ineffective, they must be replaced.