General Description

The Supplemental Air Bag Restraint System is designed to provide increased collision protection for front seat occupants 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 two basic subsystems:






1. Driver side air bag module and passenger side air bag module.
2. Electrical system including impact sensors RH primary crash front air bag sensor and bracket, LH primary crash front air bag sensor and bracket, and center cowl safing rear air bag sensor and bracket and electronic air bag diagnostic monitor with an internal backup power supply.

Driver Side Air Bag Module






CAUTION: The driver side air bag module is serviced as a complete assembly.

The driver side air bag module is mounted in the center of the steering wheel. The module consists of the following components:
1. Inflator
2. Mounting plate and retainer ring
3. Airbag
4. Steering wheel trim cover

Inflator
The air bag inflator assembly is not a serviceable item. When the sensors close, signaling a crash, electrical current flows to the air bag inflator. Inside the inflator, an igniter converts the electrical energy to thermal energy (heat), causing the ignition of the inflator gas generant. This ignition reaction combusts the sodium azide/copper oxide gas generant in the inflator, producing nitrogen gas, which inflates the air bag.

Air Bag
The air bag is constructed of neoprene coated nylon, is 711 mm (28 inch) in diameter and fills to a volume of about 0.065 cubic meters (2.3 cubic ft) in approximately 40 milliseconds. It is not a serviceable item.

Mounting Plate and Retainer Ring
The mounting plate and retainer ring attach and seal the bag assembly to the inflator. The mounting bracket is also used to attach the trim cover and to mount the entire module to the steering wheel. These items are components of the air bag module and cannot be serviced.

Steering Wheel Trim Cover
When the air bag is activated, tear seams moulded into the steering wheel trim cover separate to allow inflation of the bag. The cover is a component of the air bag assembly and is not serviceable.

Passenger Side Air Bag Module






CAUTION: The passenger side air bag module is serviced as a complete assembly.

The passenger side air bag module is mounted in the RH side of the instrument panel above the glove compartment and consists of the following components:
1. Inflator
2. Reaction housing with mounting hardware
3. Air bag
4. Trim cover

Inflator
The passenger air bag inflator is not a serviceable item. As with the driver side air bag module, an igniter inside the inflator converts electrical energy to thermal energy (heat), causing ignition of the gas generant. This ignition reaction causes combustion of the sodium azide/iron oxide gas generant producing nitrogen gas to fill the bag. Since the passenger side air bag module is much larger than the driver air bag it contains more gas generant in a different inflator configuration to produce more nitrogen gas.

Air Bag
The passenger side air bag module is constructed of rip-stop nylon. The bag has dimensions of 71 mm (28 inch) wide by 635 mm (25 inch) high by 508 mm (20 inch) deep, and fills to a volume of about 0.2 cubic meters (7 cubic ft). It is not a serviceable item.

Reaction Housing
The steel housing provides support for the inflator, a reaction surface for the bag and is used to attach the trim cover. It contains mounting brackets and rods that attach the passenger air bag to the instrument panel and is not a serviceable item.

Trim Cover
The thermo-plastic trim cover is textured and painted to match the surface of the instrument panel. It is constructed with tab-and-finger tear seams that open when the bag inflates and hinges out of the way during deployment. Its main function is to retain the air bag in the reaction housing during normal vehicle operation. It is not a serviceable item.

Air Bag Diagnostic Monitor
The air bag diagnostic monitor continually monitors all air bag system components and wiring connections for possible faults in the system. If the air bag diagnostic monitor detects a fault in the air bag system when the ignition switch is in RUN, a diagnostic trouble code will be displayed by the AIR BAG indicator. Performing system diagnostics is the main purpose of the air bag diagnostic monitor. THE AIR BAG DIAGNOSTIC MONITOR DOES NOT DEPLOY THE AIR BAGS IN THE EVENT OF A CRASH! The crash sensors are "hard wired" to the air bags, and determine when to deploy the air bags.

Several important features of the air bag diagnostic monitor and its functions within the system are described below. It is necessary that you understand these key features and functions. They will enable you to better understand and perform more efficient air bag system diagnostics.

Features and Functions






1. The, air bag diagnostic monitor illuminates the AIR BAG Indicator for approximately six seconds when the Ignition switch is turned to RUN and then turns it off. This indicates that the AIR BAG indicator is operational. If the AIR BAG indicator does not illuminate or stays on or flashes at any time, a fault has been detected by the air bag diagnostic monitor.
2. Diagnostic Trouble Codes (DTCs) may not be displayed for approximately 30 seconds after the Ignition switch has been switched to RUN. This is the amount of time it takes the air bag diagnostic monitor to perform all tests and verify system faults, if present.
3. Diagnostic trouble codes are displayed as a series of flashes and pauses of the air bag lamp. Each diagnostic trouble code, or series of flashes, represents a two-digit number. For example, a Diagnostic Trouble Code 32 is displayed as follows:
Flash flash flash - (one second pause) - flash flash - (three second pause)...
Flash flash flash - (one second pause) - flash flash - (three second pause)...
4. If a system fault exists and the AIR BAG Indicator is malfunctioning, an audible tone will be heard Indicating the need for service. The tone is a series of five sets of five beeps. This DOES NOT indicate a diagnostic trouble code 55. It means that the indicator is out and a system fault exists that requires service.
5. If a fault exists that makes unwanted air bag deployment possible, the air bag diagnostic monitor has an Internal thermal fuse that will blow automatically. This removes all power to the air bag deployment circuit. The AIR BAG indicator will flash the appropriate code to indicate the suspect circuit.

The thermal fuse is controlled by the air bag diagnostic monitor and is not serviceable.

NOTE: The thermal fuse does not blow because of excessive current flowing through it. DO NOT attempt to short circuit the thermal fuse with a circuit breaker of any other type of fuse.

6. Diagnostic trouble codes are prioritized numerically so that If two or more different faults occur at the same time, the fault having the highest priority will be displayed first. The highest priority fault will be displayed until it is corrected. After if has been corrected, the next highest priority fault will be displayed.
7. The air bag diagnostic monitor Includes an internal backup power supply. This feature provides sufficient back up power to deploy the air bags in the event that the battery or battery cables are damaged in a collision before the air bag sensors close. The backup power supply will deplete its stored energy approximately one minute after the positive battery cable is disconnected.

WARNING:
- The backup power supply energy must be depleted before any air bag component service is performed. To deplete backup power supply energy, disconnect the positive battery cable and wait one minute.

- The air bag simulator(s) must be removed and the air bag(s) reconnected before the system is reactivated.

Steering Column Wheel and Air Bag Sliding Contact
The steering column has an air bag sliding contact assembly to transfer electrical signals from the steering column to the steering wheel for the air bag system.