air bag safety class a.s.t. training instructor: john forro

Air Bag Safety Class

A.S.T. Training

Instructor: John Forro

Copyright 2000 AST Training

Why do we need airbags?

Federal Government mandate in 1989 states that we need some sort of automatic occupant safety device. Choice #1 is an automatic safety belt feature.

Very costly High failure rate

Choice #2 (Air Bag) Universal production Better safety choice

Choice #3 = Both (Best)


Is It Working? (Death Chart)

05

101520253035

Belted Unbelted RearfacedSafety

seat

Uknown

ChildrenAudult DriversAdult Passangers


Popular Beliefs T or F?

Very costly Unsafe for technicians to service Unsafe residue Killing machines for short people (10 inch

rule) A lot of accidental discharges in shops


What should we tell our customers?

Wear safety belt at all times. Pay attention to idiot lights Make passengers buckle up. Sit appropriately Strap child in correctly Drive safely!!!


How does this system work?

1. Vehicle is involved in a 10 MPH or higher front end collision.

2. At least 1 crash or safing sensor and 1 momentum/deceleration sensor activated. A safing sensor is another safety inertia type sensor located inside the control module. This sensor is used to prevent unwanted deployments.

3. Signal sent to air bag module to deploy bag.

4. Module deploys air bag in less the 7 ms on drivers side conventional systems.

5. Nitrogen gasses released through vent holes in back of bag, bag deflates.


What are the typical components in this system?

Air Bags Air Bag Module

Crash/Safing Sensors Clock Spring

System Wiring and Connectors

Smart System Devices


Front Crash/Safing Sensors

These devices are usually located in the front grill area or the kick pad/ fire wall areas. They are designed to complete a circuit back to the air bag module when a hard enough crash is measured. Most Safing sensors will be located inside the air bag control module.

Crash Sensor

Magnet


Air Bag Control Module

The air bag control module is almost always located inside the passenger compartment. There are at least 1 and sometimes 2 more safing sensors located inside this unit that must also close for deployment to occur. This unit is responsible for sending the deploy command to the air bag.

Safing Sensor


Air Bag Assembly

There could be as many as 14 of these air bags located throughout the vehicle. The main assembly is located in the steering wheel. This units main purpose is to protect the passengers and driver in the event of a crash. These could be inflated at different speeds depending on size and weight of occupants.


Clock Springs

Located inside the steering wheel. This device is used to connect the hard wired air bag harness to the systems harness while allowing the steering wheel to maintain a full range of motion.


Air Bag Circuit Harness and Connectors.

The air bag harness and connectors are yellow in color.

DO NOT ATTEMPT ANY TYPE OF REPAIRS ON THIS CIRCUIT!Typical Air

Bag Harness


Why did the government mandate the use of automatic safety devices?

Today’s vehicles are built to collapse in a collision.

Occupant safety is the #1 concern.


What does the future hold?

Smart Systems Seat Sensors

Determine size and weight of individual. Optical Sensors

Determines how close and size of occupant/car seat. Determines which way the car seat is facing.

Child-Car Seat Sensors Determines direction of car seat.

Occupant Sensors Determines if someone is present by measuring for body heat.

Air Bag Curtains Designed to protect the entire passenger compartment.


Universal Servicing Procedures

1. Disconnect the negative battery cable for at least 10 minutes to discharge module’s capacitors.

2. Use approved testing methods. No ohmmeter’s alone. Ohmmeter test voltage could deploy bag.

3. Wear eye protection.

4. Wear safety gloves.

5. Follow manufacturers’ procedures.

air bag safety class a.s.t. training instructor: john forro

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