Description & Operation

WARNING: This page is about a different car, the 2004 Mercury Mountaineer and 2004 Ford Explorer. However, it is still accessible from the selected car via links, so may be relevant.

WARNING: Accidental air bag deployment is possible. Personal injury may result. Read and follow all WARNINGS and AIR BAG SAFETY PRECAUTIONS before working on air bag system or related components.

The Supplemental Restraint System (SRS), also known as air bag system, is designed to provide increased accident protection for driver and passenger by deploying front air bags and front seat belt pretensioners in a front-end collision, and side curtain air bags in side collisions and vehicle roll-overs. Air bags deploy in about 40 milliseconds after impact sensors close. Air bag system is designed to be used with 3-point seat belts.

During a front-end collision, the Restraints Control Module (RCM), using input from front crash sensor, discriminates between an event that warrants air bag and seat belt pretensioner deployment and an event that does not. Using inputs from driver seat track position sensor and seat belt switches, in conjunction with front crash sensor inputs, RCM determines which air bags to deploy and at what deployment rate. In a crash of sufficient force, the RCM signals the air bag modules and seat belt pretensioners to simultaneously deploy.

On models equipped with side curtain air bags that are involved in a side or lateral collision, the RCM, using inputs from right and/or left side crash sensors and roll-over sensors, discriminates between an event that warrants side curtain air bag deployment and an event that does not. In lateral collisions of sufficient force, and vehicle roll-overs, the RCM signals the right and/or left side curtain air bag module to deploy.

Air Bag system includes the following components: RCM, impact and safing sensors (located inside the RCM), back-up power supply (also located inside the RCM), front crash sensor, dual-stage driver-side air bag module, dual-stage passenger-side air bag module, right and left side crash sensors, right and left side curtain air bag modules, right and left front seat belt pretensioners, right and left front seat belt buckle switches, seat position sensor, AIR BAG warning light, clockspring and associated wiring harnesses.