Supplemental Restraint System (SRS)

The Supplemental Air Bag Restraint System (SRS) is designed to provide increased accident protection IN ADDITION TO that provided by the three-point safety belt system. Safety belt use is necessary to obtain the best occupant protection and to receive the full advantages of the supplemental air bag. FORD RECOMMENDS THE USE OF SAFETY BELT SYSTEMS FOR ALL VEHICLE OCCUPANTS.

The Supplemental Air Bag Restraint System consists of:
- Electrical system
- Driver side air bag module
- Sensors (crash and safing)
- Air bag diagnostic monitor
- Airbag lamp
- Tone generator (internal to the air bag diagnostic monitor)

Electrical System
The Supplemental Air Bag Restraint System is powered directly from the battery. The SRS can function with the ignition switch in any position, including OFF and LOCK. The SRS can also function when the driver's seat is unoccupied. The electrical system performs three main functions:
- Detects impacts
- Supplies electrical power to the igniter
- Monitors the system to determine system readiness

The electrical system components include:
- Air bag lamp
- Wiring harness and clock spring assembly
- Sensors (crash and safing)
- Igniter

System Operation
The following four steps show how the SRS works:

NOTE: Steps 1-3 take place in a fraction of a second.

1. The sensors in the vehicle detect a severe frontal impact. When at least one crash sensor and the safing sensor close at the same time, electric current flows to the inflator and ignites the chemicals.
2. The chemicals then rapidly burn in the metal container. The rapid burning produces nitrogen gas and small amounts of dust. The nitrogen gas and dust are cooled and filtered during inflation of the air bag.
3. The inflating air bag splits open the trim cover. The air bag then rapidly unfolds and inflates in front of the driver.
4. After inflation, the gas empties through holes in the air bag. The air bag deflates at once.