Air Bag Systems: Description and Operation
DESCRIPTION & OPERATIONThe Supplemental Restraint System (SRS) is designed to supplement drivers and passengers seat belts to help reduce risk or severity of injury to front seat occupants by activating and deploying a driver, and, if equipped, passenger air bag in certain frontal collisions.
Chrysler and Jeep light duty trucks and vans use two types of air bag control modules (ACM). The Air Bag System Diagnostic Module (ASDM) is mechanically triggered, using two front impact sensors and a sensor inside the ACM. The Air Bag Electronic Control Module (AECM) used on the Full Size Van, and 1994-96 Caravan, Town & Country and Voyager models, is electronically triggered, using an ACM internal sensor, only. The other major SRS components are air bag modules and clocksprings. If any of these parts should fail, they must be replaced, as they cannot be repaired.
The Cherokee uses a mechanical air bag system comprising three major components: driver air bag module, impact sensor/inflator and arming/disarming mechanism.
The ASDM systems are designed so that the air bag(s) will deploy when the safing sensor plus either impact sensor simultaneously activate while ignition switch in On position. The AECM SRS air bag(s) will deploy when the internal electronic sensor is triggered.
The fasteners, screws and bolts used for air bag components have special coatings and are specifically designed for air bag systems. They must not be replaced with substitutes. If fastener replacement is required, use correct fasteners provided in service package.