Sprinter 2500 V6-3.0L DSL Turbo VIN 45 (2007)
Air Bag: Description and Operation
Curtain Airbag
Description
DESCRIPTION
Side curtain airbags are available optional equipment for this vehicle when it is also equipped with dual front airbags. These airbags are passive,
inflatable, Supplemental Restraint System (SRS) components, and vehicles with this equipment can be readily identified by a molded AIRBAG
identification logo located on the garnish molding above each front door near the B pillar. This system is designed to reduce injuries to the vehicle
occupants in the event of a side impact collision.
Vehicles equipped with side curtain airbags have two individually controlled curtain airbag units. These airbag units are concealed and mounted above
and forward of the front door openings where they are each secured to the A-pillar and the roof side rail. Each folded airbag cushion is contained within
a sleeve-like molded plastic garnish molding (3) that extends up the A-pillar from the belt line of the vehicle and along the roof rail to just forward of the
B-pillar.
A tether extends down the A-pillar from the front of the airbag cushion, where it is secured to the airbag inflator bracket (4) near the base of the pillar at
the belt line. On vehicles equipped with curtain airbags, the back side of the A-pillar trim is also equipped with a tether that is secured to the upper
A-pillar with a screw.
The hybrid-type inflator (1) for each airbag is connected to the airbag cushion by a tubular manifold (2). Two screws secure the inflator bracket with the
inflator and the initiator (5) to the A-pillar. Another screw secures a bracket at each end of the garnish molding to the to the inner roof rail.
A two-wire take out of the vehicle body wire harness connects the inflator initiator to the vehicle electrical system with a keyed and latched connector
insulator. The body wire harness connects the airbag unit to the Occupant Restraint Controller (ORC) (also known as the lowline or highline airbag
control unit/ARCADE).
The side curtain airbag unit cannot be adjusted or repaired and must be replaced if deployed, ineffective, or in any way damaged. Once a side curtain
airbag has been deployed, the complete airbag unit and all other visibly damaged components must be replaced.
Operation
OPERATION
Each side curtain airbag is deployed individually by an electrical signal generated by the Occupant Restraint Controller (ORC) (also known as the
lowline or highline airbag control unit/ARCADE) to which it is connected through left or right curtain airbag line 1 and line 2 (or squib) circuits. The
hybrid-type inflator assembly for each airbag contains a small canister of highly compressed inert gas. When the ORC sends the proper electrical signal
to the airbag inflator, the electrical energy creates enough heat to ignite chemical pellets within the inflator.
Once ignited, these chemicals burn rapidly and produce the pressure necessary to rupture a containment disk in the inert gas canister. The inflator and
inert gas canister are sealed and connected to a tubular manifold so that all of the released gas is directed into the folded curtain airbag cushion, causing
the cushion to inflate. As the airbag cushion inflates it will split the garnish molding at a predetermined breakout line and drop down from the roof rail
along the side glass and body pillars to form a curtain-like cushion to protect the vehicle occupants during a side impact collision.
The front tether keeps the front portion of the side curtain bag taut, thus ensuring that the bag will deploy in the proper position. The tether on the back
of the A-pillar trim controls the travel of this trim piece as it is displaced by the inflating curtain airbag. Following the airbag deployment, the airbag
cushion deflates by venting the inert gas through the loose weave of the cushion fabric, and the deflated cushion hangs down loosely from the roof rail.
Proper diagnosis of the side curtain airbag inflator and squib circuits requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic
