General Description

The Passive 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 RH primary crash front air bag sensor and bracket, LH primary crash front air bag sensor and bracket, and air bag diagnostic monitor.

DRIVER SIDE AIR BAG MODULE






NOTE: The driver side air bag module is serviced as a complete assembly, except for the horn blowing switch assembly which attaches to driver side air bag module.

The driver side air bag module is mounted in the center of the steering wheel. The driver side air bag module consists of the following components:
- Inflator.
- Air bag.
- Mounting plate and retainer ring.
- Steering wheel trim cover.
- Switch assembly-horn blowing.

Inflator
The air bag inflator assembly is not a serviceable item.
- When the sensor system closes, 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 solid gas generant in the inflator, producing nitrogen gas, which inflates the air bag.

Air Bag
The driver side air bag:
- Is constructed of silicone-coated nylon on the front side of the air bag. The rear half is uncoated.
- Is 648 mm (25.5 inch) in diameter.
- Fills to a volume of about 0.05 cubic meter (1.75 cubic ft) in approximately 40 milliseconds.
- 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.
- Also attach the trim cover and mount the entire driver side air bag module to the steering wheel.
- Are components of the driver side air bag module and cannot be serviced.

Steering Wheel Trim Cover
The steering wheel trim cover:
- Encases the driver side air bag module and horn switch.
- Has moulded-in tear seams that separate to allow inflation of the bag.
- Is a component of the driver side air bag module and is not serviceable.
- Must not be repainted for any reason.

PASSENGER SIDE AIR BAG MODULE






NOTE: 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. The passenger side air bag module consists of the following components:
- Inflator.
- Air bag.
- Reaction housing with mounting hardware.
- Trim cover.

Inflator
The passenger air bag inflator operates as follows:
- An igniter inside the inflator converts electrical energy to thermal energy (heat), causing ignition of the gas generant.
- The ignition reaction causes combustion of the solid gas generant producing nitrogen gas to fill the bag.
- Since the passenger side air bag module is much larger than the driver side air bag module, it contains more gas generant in a different inflator configuration to produce more nitrogen gas.
- It is a component of the passenger side air bag module and is not serviceable.

Air Bag
The passenger side air bag:
- Is constructed of rip-stop nylon.
- Is not a serviceable item.

Reaction Housing
The steel reaction housing:
- Supplies support for the inflator
- Provides a reaction surface for the passenger side air bag module.
- Is used to attach the trim cover.
- Contains mounting brackets that attach the passenger side air bag module to the instrument panel.
- Is not a serviceable item.

Trim Cover
The thermo-plastic trim cover:
- Is textured and painted to match the surface of the instrument panel.
- Is constructed with a moulded-in tear seam that separates when the air bag inflates, and hinges out of the way during deployment.
- Retains the air bag in the reaction housing during vehicle operation.
- 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 when the ignition switch is in RUN.
- If the air bag diagnostic monitor detects a fault in the air bag system, a Diagnostic Trouble Code (DTC) will be written to the air bag diagnostic monitor's Non-Volatile Random Access Memory (NVRAM).
- This diagnostic trouble code will then be displayed on the AIR BAG indicator lamp.
- After servicing, the diagnostic trouble code may then be cleared from NVRAM.
- 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 COLLISION.
- The crash sensors determine air bag deployment. The air bag diagnostic monitor monitors the system for readiness.

Several important features of the air bag diagnostic monitor and its functions within the system are described below. It is necessary that these key features and functions are well understood.

AIR BAG SYSTEM FUNCTIONS






- The air bag diagnostic monitor illuminates the AIR BAG indicator for approximately 6 seconds when the ignition switch is turned to RUN and then turns the air bag indicator OFF. This indicates that the AIR BAG indicator is operational. If the AIR BAG indicator does not illuminate at all, stays on continuously, or flashes at any time, then a fault has been detected by the air bag diagnostic monitor.
- Diagnostic Trouble Codes (DTCs), if present, will begin flashing within 30 seconds after the ignition switch has been turned 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.
- Diagnostic trouble codes are displayed as a series of flashes and pauses of the AIR BAG indicator. Diagnostic trouble codes are two-digit numbers. Example: A DTC 32 is displayed as follows:
Flash flash flash - (two second pause) - flash flash - (five second pause)...
Flash flash flash - (two second pause) - flash flash - (five second pause)...
- Diagnostic trouble codes are prioritized numerically so that if two or more faults occur at the same time, the diagnostic trouble code with the highest priority will be displayed.
- After the DTC is displayed five times, the AIR BAG indicator will illuminate continuously until the ignition switch is cycled.
- The air bag diagnostic monitor incorporates Non Volatile Random Access Memory (NVRAM) to store diagnostic trouble codes and retain them indefinitely. The air bag diagnostic monitor will always flash the highest priority diagnostic trouble code stored in NVRAM. Diagnostic trouble codes may be cleared from the air bag diagnostic monitor after the fault conditions are serviced.
- The air bag diagnostic monitor distinguishes between hard and intermittent (or repaired) fault conditions.
- Each diagnostic trouble code number 12 through 45 represents a hard fault (a fault that is still present). Hard diagnostic trouble codes are higher priority than intermittent diagnostic trouble codes, and may not be cleared from NVRAM.
- Each of these hard diagnostic trouble codes has an equivalent diagnostic trouble code which is the sum of the diagnostic trouble code number plus 40. This equivalent diagnostic trouble code will indicate that an intermittent condition exists, or that a hard condition has been repaired.
- Only the intermittent (repaired) diagnostic trouble codes, numbers 52 through 85, may be cleared from the air bag diagnostic monitor. Example: A Diagnostic Trouble Code 32 indicates that high resistance in the driver side air bag circuit has been, and still is, present. A DTC 72 (32 + 40) indicates that high resistance in the driver side air bag circuit existed at one time, but no longer exists due to an intermittent condition or a repair made to the circuit.
- If a system fault exists and the AIR BAG indicator is not functioning, an audible tone will be heard indicating a need for service. The tone is a series of five sets of five beeps. This DOES NOT indicate a diagnostic trouble code 55 or any other diagnostic trouble code. The AIR BAG indicator must be serviced before diagnostic trouble codes can be determined.
- If a fault exists that makes unwanted air bag deployment possible, the air bag diagnostic monitor will attempt to remove deployment power by turning on a solid state switch to blow the 10 A battery fuse.

WARNING: Under no circumstances substitute another fuse value for the 10 A battery fuse. Any fuse other than 10 A may cause disarming failure and may result in danger to the occupants of the vehicle. Do not attempt to replace the 10 A battery fuse until the air bag system first has been deactivated.

- If the 10 A battery fuse has successfully been blown by the air bag diagnostic monitor, the air bag diagnostic monitor will not attempt to blow it again until the proper fault has been serviced and cleared. The air bag diagnostic monitor will store both the diagnostic trouble code that caused it to blow the 10 A battery fuse and the loss of deployment power Diagnostic Trouble Code (DTC) 12. The loss of deployment power diagnostic trouble code is the highest priority.
- The air bag diagnostic monitor includes an internal backup power supply. This feature provides sufficient backup power to deploy the air bags in the event that the battery or battery cables are damaged in a collision before the crash sensors are activated. The backup power supply will deplete its stored energy approximately one minute after the negative battery cable is disconnected.

WARNING: The backup power supply energy must be depleted before any air bag component service is performed. To deplete the backup power supply energy, disconnect the negative battery cable and wait one minute to avoid accidental deployment and possible personal injury.

- The air bag diagnostic monitor incorporates an internal safing sensor. Proper mounting of the air bag diagnostic monitor and bracket assembly is critical to the function and performance of the air bag system.
- The air bag diagnostic monitor and bracket assembly is non-serviceable and must be replaced as a unit in the event of failure.

STEERING COLUMN WHEEL AND AIR BAG SLIDING CONTACT
The steering column has an air bag sliding contact to transfer electrical signals from the steering column to the steering wheel for the air bag system.