Dodge Ram Truck 1500-2500-3500. Manual - part 559

Vehicles equipped with side curtain airbags have two
individually controlled curtain airbag units. These air-
bag units are concealed and mounted above the
headliner where they are each secured to one of the
roof side rails (5). Each folded airbag cushion is con-
tained within a long extruded plastic channel (8) that
extends along the roof rail from the A-pillar (6) at the
front of the vehicle to just behind the B-pillar (2) on
standard cab models, and to just behind the C-pillar
(2) on quad cab models.

A long tether (7) extends down the A-pillar from the
front of the airbag cushion, where it is retained to the
pillar with plastic push-in routing clips and it is secured
to the base of the A-pillar near the belt line with a
screw.

The hybrid-type inflator (3) for each airbag is secured to the roof rail at the rear of the airbag unit behind the B-pillar
(standard cab) or C-pillar (quad cab), and is connected to the airbag cushion by a long tubular manifold (4). The
inflator bracket and the extruded airbag cushion channel are located with plastic push-in fasteners to the roof rail,
then secured with screws to spring nuts located in the roof rail.

A two-wire take out of the body wire harness with a keyed and latched connector insulator (1) on the B-pillar (stan-
dard cab) or C-pillar (quad cab) connects directly to an integral receptacle on the inflator initiator. The body wire
harness connects the airbag unit to the Airbag Control Module (ACM).

The side curtain airbag unit cannot be adjusted or repaired and must be replaced if deployed, faulty, or in any way
damaged. Once a side curtain airbag has been deployed, the complete airbag unit, the headliner, the upper A, B,
and C-pillar trim, and all other visibly damaged components must be replaced.

OPERATION

Each side curtain airbag is deployed individually by an electrical signal generated by the Airbag Control Module
(ACM) 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 ACM
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 drop down from the roof rail between the edge of the headliner and the side glass/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. Following the airbag deployment, the airbag cushion quickly 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.

REMOVAL

WARNING: To avoid personal injury or death, on vehicles equipped with airbags, disable the supplemental
restraint system before attempting any steering wheel, steering column, airbag, seat belt tensioner, impact
sensor, or instrument panel component diagnosis or service. Disconnect and isolate the battery negative
(ground) cable, then wait two minutes for the system capacitor to discharge before performing further diag-
nosis or service. This is the only sure way to disable the supplemental restraint system. Failure to take the
proper precautions could result in accidental airbag deployment.

WARNING: To avoid personal injury or death, when removing a deployed airbag, rubber gloves, eye protec-
tion, and a long-sleeved shirt should be worn. There may be deposits on the airbag unit and other interior
surfaces. In large doses, these deposits may cause irritation to the skin and eyes.

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WARNING: To avoid personal injury or death, use extreme care to prevent any foreign material from enter-
ing the side curtain airbag, or becoming entrapped between the side curtain airbag cushion and the head-
liner. Failure to observe this warning could result in occupant injuries upon airbag deployment.

NOTE: The following procedure is for replacement of a faulty or damaged side curtain airbag. If the airbag
is faulty or damaged, but not deployed, review the recommended procedures for handling non-deployed
supplemental restraints. (Refer to 8 - ELECTRICAL/RESTRAINTS - STANDARD PROCEDURE - HANDLING
NON-DEPLOYED SUPPLEMENTAL RESTRAINTS). If the side curtain airbag has been deployed, review the
recommended procedures for service after a supplemental restraint deployment before removing the airbag
from the vehicle. (Refer to 8 - ELECTRICAL/RESTRAINTS - STANDARD PROCEDURE - SERVICE AFTER A
SUPPLEMENTAL RESTRAINT DEPLOYMENT).

1. Disconnect and isolate the battery negative cable.

Wait two minutes for the system capacitor to dis-
charge before further service.

2. Remove the headliner from the vehicle. (Refer to

23 - BODY/INTERIOR/HEADLINER - REMOVAL).

3. Remove the screw (6) that secures the side curtain

airbag tether retainer (5) to the base of the A-pillar
near the belt line.

4. Disengage the two side curtain airbag tether plastic

retainer clips (4) from the A-pillar.

5. Disconnect the body wire harness connector for the

side curtain airbag (9) from the connector recepta-
cle at the back of the airbag inflator.

6. Remove the four screws (standard cab) or six

screws (quad cab) (3) that secure the side curtain
airbag inflator and manifold tube brackets to the spring nuts (2) in the roof rail (1).

7. Grasp the extruded plastic side curtain airbag channel firmly and pull it straight away from the roof rail far

enough to disengage all three (standard cab) or five (quad cab) plastic push-in fasteners (8) that secure it.

8. Remove the side curtain airbag (7) from the vehicle as a unit.

INSTALLATION

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1. Check to be certain that the four (standard cab) or

six (quad cab) spring nuts (2) that secure the side
curtain airbag inflator and manifold tube brackets
are properly installed and in good condition in the
roof rail (1).

2. Position the side curtain airbag (7) into the vehicle

as a unit.

3. Align all three (standard cab) or five (quad cab)

plastic

push-in

fasteners

(8)

that

secure

the

extruded plastic side curtain airbag channel with
their holes in the roof side rail and push them
straight into the roof rail until they are fully seated.

4. Working from the rear of the vehicle to the front,

install and tighten the four screws (standard cab) or
six screws (quad cab) (3) that secure the side cur-
tain airbag inflator and manifold tube brackets to
the nuts in the roof rail. Tighten the screws to 5 N·m (40 in. lbs.).

5. Reconnect the body wire harness connector for the side curtain airbag (9) to the connector receptacle at the

back of the airbag inflator. Be certain the connector is fully engaged and latched.

6. Engage the two side curtain airbag tether plastic retainer clips (4) into the A-pillar.

7. Install and tighten the screw (6) that secures the side curtain airbag tether retainer (5) to the base of the A-pillar

near the belt line. Tighten the screw to 6 N·m (55 in. lbs.).

8. Reinstall the headliner into the vehicle. (Refer to 23 - BODY/INTERIOR/HEADLINER - INSTALLATION).

9. Do not reconnect the battery negative cable at this time. The supplemental restraint system verification test pro-

cedure should be performed following service of any supplemental restraint system component. (Refer to 8 -
ELECTRICAL/RESTRAINTS - STANDARD PROCEDURE - VERIFICATION TEST).

AIR BAG-DRIVER

DESCRIPTION

The color-keyed, injection molded, thermoplastic driver
airbag protective trim cover (2) is the most visible part
of the driver airbag. The driver airbag is located in the
center of the steering wheel (1), where it is secured
with two screws to the armature of the four-spoke
steering wheel. All models have a chrome Dodge Ram
emblem in the center of the trim cover. Concealed
beneath the driver airbag trim cover are the horn
switch, the folded airbag cushion, the airbag cushion
retainer, the airbag housing, the airbag inflator, and
the retainers that secure the inflator to the airbag

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housing.

The airbag cushion, housing (5), and inflator (3) are
secured within an integral receptacle molded into the
back of the trim cover (4). The four vertical walls of
this receptacle have a total of twelve small windows
with blocking tabs that are engaged by twelve hook
formations around the perimeter of the airbag housing.
Each hook is inserted through one of the windows and
the blocking tab in each window keeps the hook prop-
erly engaged with the trim cover, locking the trim
cover securely into place on the airbag housing.

The resistive membrane-type horn switch is secured
with heat stakes to the inside surface of the driver air-
bag trim cover, between the trim cover and the folded
airbag cushion. The horn switch ground pigtail wire
has an eyelet terminal connector that is captured
beneath a flanged nut on the upper right inflator
mounting stud on the back of the housing. The horn
switch feed pigtail wire has a black, molded plastic
insulator (1) that is secured by an integral retainer in a
locator hole near the upper right corner of the airbag
housing and is connected to the vehicle electrical system through a dedicated take out and connector of the steer-
ing wheel wire harness. Both horn switch wires are routed through an integral notch in the center of the upper edge
of the airbag housing stamping.

The airbag used in this model is a multistage, Next Generation-type that complies with revised federal airbag stan-
dards to deploy with less force than those used in some prior models. A 71 centimeter (28 inch) diameter, radial
deploying fabric cushion with internal tethers is used. The airbag inflator is a dual-initiator, non-azide, pyrotechnic-
type unit with four mounting studs and is secured to the stamped metal airbag housing by four flanged hex nuts.
Two keyed and color-coded connector receptacles on the driver airbag inflator connect the two inflator initiators to
the vehicle electrical system through two yellow-jacketed, two-wire pigtail harnesses of the clockspring.

The driver airbag unit cannot be repaired, and must be replaced if deployed or in any way damaged. The driver
airbag trim cover and horn switch unit may be disassembled from the driver airbag unit, and is available for sepa-
rate service replacement.

OPERATION

The multistage driver airbag is deployed by electrical signals generated by the Airbag Control Module (ACM)
through the driver airbag squib 1 and squib 2 circuits to the two initiators in the airbag inflator. By using two initi-
ators, the airbag can be deployed at multiple levels of force. The force level is controlled by the ACM to suit the
monitored impact conditions by providing one of three delay intervals between the electrical signals provided to the
two initiators. The longer the delay between these signals, the less forcefully the airbag will deploy.

When the ACM sends the proper electrical signals to each initiator, the electrical energy generates enough heat to
initiate a small pyrotechnic charge which, in turn ignites chemical pellets within the inflator. Once ignited, these
chemical pellets burn rapidly and produce a large quantity of inert gas. The inflator is sealed to the back of the
airbag housing and a diffuser in the inflator directs all of the inert gas into the airbag cushion, causing the cushion
to inflate. As the cushion inflates, the driver airbag trim cover will split at predetermined breakout lines, then fold
back out of the way along with the horn switch unit. Following an airbag deployment, the airbag cushion quickly
deflates by venting the inert gas towards the instrument panel through vent holes within the fabric used to construct
the back (steering wheel side) panel of the airbag cushion.

Some of the chemicals used to create the inert gas may be considered hazardous while in their solid state before
they are burned, but they are securely sealed within the airbag inflator. Typically, both initiators are used and all
potentially hazardous chemicals are burned during an airbag deployment event. However, it is possible for only one
initiator to be used during a deployment due to an airbag system fault; therefore, it is necessary to always confirm
that both initiators have been used in order to avoid the improper disposal of potentially live pyrotechnic or hazard-
ous materials. (Refer to 8 - ELECTRICAL/RESTRAINTS - STANDARD PROCEDURE - SERVICE AFTER A SUP-
PLEMENTAL RESTRAINT DEPLOYMENT).

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