Inflatable Restraint Seat Belt Retractor Pretensioners

WARNING: This page is about a different car, the 2009 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.

The seat belt retractor pretensioners consist of a housing, a seat belt retractor, the seat belt webbing, an initiator, and a canister of gas generating materials. The initiator is part of the seat belt pretensioner deployment loop. During a collision of sufficient force, the sensing and diagnostic module (SDM) sends current through the seat belt deployment loops. The initiator ignites the material in the canister producing a rapid generation of gas which deploys the seat belt pretensioners and retracts the seat belts webbing removing all slack in the shoulder belt. Depending on the severity of the collision, the seat belt pretensioners may deploy without the frontal inflator modules deploying, or they will deploy immediately before the frontal inflator modules deploy. Each seat belt pretensioner connector has a shorting bar to prevent unwanted deployment when the connector is disconnected.