Cobalt L4-2.0L SC VIN P (2005)
Seat Belt Tensioner: Description and Operation
INFLATABLE RESTRAINT SEAT BELT RETRACTOR PRETENSIONER
The seat belt pretensioner modules contain a housing, a seat belt retractor, the seat belt webbing, an initiating device, and a canister of gas generating
material. The initiator is part of the seat belt pretensioner deployment loop. When the vehicle is involved in a collision of sufficient force, the sensing and
diagnostic module (SDM) will cause current to flow through the deployment loops to the initiator. Current passing through the initiator ignites the
material in the canister producing a rapid generation of gas and the release of compressed gas, if present. The gas produced from this reaction deploys
the seat belt pretensioner and retracts the seat belt webbing, which removes slack in the seat belt.
Depending on the severity of the collision, the seat belt pretension may deploy without the frontal inflator modules deploying, or they will deploy
immediately before the frontal inflator modules deploy. As soon as 3 distinct deployment commands, representing different events, have been issued to
any belt pretensioner, the SDM shall be considered to not be reusable.
Each seat belt pretensioner is equipped with a shorting bar located on the connector of the pretensioner. The shorting bar shorts the seat belt pretensioner
deployment loop circuitry to prevent unwanted deployment of the pretensioner when servicing the seat belt pretensioner.
