Part 3

Passenger Side Airbag Module Remove/Install:

PASSENGER AIRBAG
The passenger airbag door on the instrument panel above the glove box is the most visible part of the passenger airbag. The airbag used in this model is a Next Generation-type that complies with revised federal airbag standards to deploy with less force than those used in some prior models. The passenger airbag is located in the instrument panel in front of the front seat passenger seating position, where it is secured with four screws to the instrument panel structural duct. Concealed beneath the passenger airbag door are the folded airbag cushion, the airbag retainer or housing, and the airbag inflator. The airbag inflator is a hybrid-type unit that is secured to and sealed within the extruded aluminum airbag housing along with the folded airbag cushion. A yellow connector on the end of a short, two-wire pigtail harness connects the passenger airbag inflator to the vehicle electrical system.

The molded plastic passenger airbag door also serves as a trim cover and has four flanges that secure it in place. Two of these flanges are the return flanges, which extend over the upper and lower edges of the airbag housing. Three keyed slots on each of these return flanges are engaged with tabs on the airbag housing to secure the door to the housing. The other two flanges are the mounting flanges, which extend upward and downward respectively from the upper and lower edges of the passenger airbag door and are secured with four screws to the instrument panel structural duct after the airbag housing has been secured to the instrument panel. Following a passenger airbag deployment, the passenger airbag and the passenger airbag door must be replaced. The passenger airbag cannot be repaired, and must be replaced if faulty or in any way damaged. The passenger airbag door can be disassembled from the air-bag housing and replaced as a separate service item.

The passenger airbag is deployed by an electrical signal generated by the Airbag Control Module (ACM) through the passenger airbag line 1 and line 2 (or squib) circuits. The hybrid-type inflator assembly includes a small canister of highly compressed argon gas. when the ACM sends the proper electrical signal to the airbag inflator, the electrical energy generates enough heat to ignite chemical pellets within the inflator. Once ignited, these chemical pellets burn rapidly and produce the pressure necessary to rupture a containment disk in the argon gas canister. The inflator and argon gas canister are sealed to the airbag cushion so that all of the released argon gas is directed into the airbag cushion, causing the cushion to inflate. As the cushion inflates, the passenger airbag door will split at predetermined breakout lines, then fold back over the top of the instrument panel and out of the way. Following an airbag deployment, the airbag cushion quickly deflates by venting the argon gas through the porous fabric material used on each end panel of the airbag cushion.

Some of the chemicals used to create the pressure to burst the argon gas containment disk are considered hazardous in their solid state, before they are burned, but they are securely sealed within the AIRBAG inflator. However, the gas that is produced when the chemicals are burned is harmless. A small amount of residue from the burned chemicals may cause some temporary discomfort if it contacts the skin, eyes, or breathing passages. If skin or eye irritation is noticed, rinse the affected area with plenty of cool, clean water. If breathing passages are irritated, move to another area where there is plenty of clean, fresh air to breath. If the irritation is not alleviated by these actions, contact a physician immediately.

Fig.31 Seat Belt Switch:

SEAT BELT SWITCH
The seat belt switch is a small, normally closed, single pole, single throw, leaf contact, momentary switch. Only one seat belt switch is installed in the vehicle, and it is integral to the buckle of the driver seat belt buckle-half, located between the inboard side of the driver side front seat and the floor panel transmission tunnel. The seat belt switch is connected to the vehicle electrical system through a two-wire pigtail wire and connector on the seat belt buckle-half, which is connected to a wire harness connector and take out of the instrument panel floor wire harness routed along the left side of the floor panel transmission tunnel under the center floor console.

The seat belt switch cannot be adjusted or repaired and, if faulty or damaged, the entire driver seat belt buckle-half unit must be replaced.

The seat belt switch is designed to control a path to ground for the seat belt switch sense input of the instrument cluster. When the driver side seat belt tip-half is inserted in the seat belt buckle, the switch opens the path to ground; and, when the driver side seat belt tip-half is removed from the seat belt buckle, the switch closes the ground path. The switch is actuated by the latch mechanism within the seat belt buckle.

The seat belt switch receives ground through its pigtail wire connection to the instrument panel floor wire harness from another take out of the instrument panel wire harness. An eyelet terminal connector on that ground take out is secured under a ground screw on the right instrument panel end bracket. The seat belt switch is connected in series between ground and the seat belt switch sense input of the instrument cluster.