Air Bag: Description and Operation
The inflator modules consist of an inflatable bag and an inflator (a canister of gas-generating material and an initiating device). When the vehicle is in a frontal crash of sufficient force, the inflatable restraint Sensing and Diagnostic Module (SDM) causes current to flow through the deployment loops. Current passing through the initiator ignites the material in the inflator module. The gas produced from this reaction rapidly inflates the air bag.
There is a shorting bar on the inflatable restraint steering wheel module side of the upper steering column connector which connects the inflatable restraint steering wheel module coil to the inflatable restraint steering wheel module. The shorting bar shorts across the inflatable restraint steering wheel module circuits when the upper steering column connector is disconnected. The circuit to the inflatable restraint steering wheel module is shorted in this way to help prevent unwanted deployment of the air bag when servicing the inflatable restraint steering wheel module, the steering column or other SIR system components.
There is a shorting bar on the inflatable restraint I/P module connector which connects to the SIR wiring harness. The shorting bar shorts across the inflatable restraint I/P module circuits when the inflatable restraint I/P module connector is disconnected. The circuit to the inflatable restraint I/P module is shorted in this way to help prevent unwanted deployment of the air bag when servicing the inflatable restraint I/P module, the instrument panel or other SIR system components.