The seat belt tensioner cannot be repaired and, if
faulty or damaged, the entire outboard front seat belt
and retractor unit must be replaced. If the front air-
bags have been deployed, the seat belt tensioners
have also been deployed. The seat belt tensioner is
not intended for reuse and must be replaced follow-
ing a deployment. A locked retractor that will not
allow the seat belt webbing to be retracted or
extracted is a sure indication that the seat belt ten-
sioner has been deployed and requires replacement.
(Refer to 8 - ELECTRICAL/RESTRAINTS/FRONT
OUTBOARD SEAT BELT & RETRACTOR - REMOV-
AL).
OPERATION
The seat belt tensioners are deployed by a signal
generated by the Airbag Control Module (ACM)
through the driver and passenger seat belt tensioner
line 1 and line 2 (or squib) circuits. When the ACM
sends the proper electrical signal to the tensioners,
the electrical energy generates enough heat to ini-
tiate a small pyrotechnic gas generator. The gas gen-
erator is installed at the top of the tensioner housing
which contains a long metal tape that is routed
through two chambers within the housing. Each end
of the tape is wound around the outer sleeve of a
mechanical clutch mechanism secured to one end of
the torsion bar upon which the retractor spool is
secured. As the gas expands, it is directed against
the metal tape within the two chambers of the hous-
ing causing the tape to unwind from the clutch
sleeve. As the clutch rotates it engages the torsion
bar, which drives the seat belt retractor spool causing
the slack to be removed from the seat belt.
Once a seat belt tensioning sequence has been
completed, the forward momentum of the occupant
results in deformation of the torsion bar. As the tor-
sion bar deforms it allows the seat belt webbing to
unwind from the retractor spool, which causes the
metal tape to be wound back onto the clutch sleeve
until it is pulled tight against two cutter blades
within the housing, which immediately cut the metal
tape.
Removing excess slack from the seat belt not only
keeps the occupant properly positioned for an airbag
deployment following a frontal impact of the vehicle,
but also helps to reduce injuries that the occupant
might experience in these situations as a result of a
harmful contact with the steering wheel, steering col-
umn, instrument panel and/or windshield. The tor-
sion bar is designed to deform in order to control the
loading being applied to the occupant by the seat belt
during a frontal impact, further reducing the poten-
tial for occupant injuries.
The ACM monitors the condition of the seat belt
tensioners through circuit resistance. The ACM willilluminate the airbag indicator in the ElectroMe-
chanical Instrument Cluster (EMIC) and store a
Diagnostic Trouble Code (DTC) for any fault that is
detected. For proper diagnosis of the seat belt ten-
sioners, a DRBIIItscan tool is required. Refer to the
appropriate diagnostic information.
SEAT BELT TENSION
REDUCER
DESCRIPTION
A seat belt tension reducer is standard equipment
for the driver side front outboard seat belt on stan-
dard cab versions of this model (Fig. 45). The tension
reducer is integral to the driver side front outboard
seat belt and retractor unit, which is secured to the
inner B-pillar on the left side of the vehicle. The
retractor is concealed beneath the molded plastic
inner B-pillar trim. The seat belt tension reducer
consists primarily of a 12-volt Direct Current (DC)
solenoid and an integral connector receptacle that is
located on the forward facing end housing of the
retractor. The seat belt tension reducer is controlled
by a battery current output of the ignition switch and
a ground path provided by the seat belt switch, and
is connected to the vehicle electrical system through
a dedicated take out of the body wire harness by a
keyed and latching molded plastic connector insula-
tor to ensure a secure connection.
The seat belt tension reducer cannot be repaired
and, if faulty or damaged, the entire driver side front
Fig. 45 Seat Belt Tension Reducer
1 - TENSIONER HOUSING OR CHAMBER
2 - GAS GENERATOR
3 - TENSIONER PIGTAIL WIRE
4 - SPOOL
5 - TENSION REDUCER (DRIVER SIDE ON STANDARD CAB
ONLY)
6 - REDUCER CONNECTOR RECEPTACLE
8O - 48 RESTRAINTSDR
SEAT BELT TENSIONER (Continued)
outboard seat belt and retractor unit must be
replaced. (Refer to 8 - ELECTRICAL/RESTRAINTS/
FRONT OUTBOARD SEAT BELT & RETRACTOR -
REMOVAL).
OPERATION
The seat belt tension reducer is controlled by a
ground signal received from the seat belt switch on
the seat belt switch sense circuit and a battery cur-
rent signal received from the ignition switch on the
fused ignition switch output (run-accessory) circuit.
When the seat belt switch is closed (the driver side
front seat belt is fastened) and the ignition switch is
in the On or Accessory positions, the seat belt tension
reducer solenoid is energized. When the solenoid is
energized, it actuates a mechanism within the driver
side front outboard seat belt retractor to reduce the
normal recoil spring tension exerted by the retractor
spool, which is designed to reel in the seat belt web-
bing onto the spool. When the driver side seat belt is
unbuckled or if the ignition switch is turned to any
position except On or Accessory, the tension reducer
solenoid is de-energized and the normal recoil spring
tension of the retractor is restored.
The action of the seat belt tension reducer results
in improved seat belt comfort for the driver. Reducing
the seat belt retractor recoil spring tension is desir-
able on standard cab models of this vehicle and not
on the quad cab model due to the different mounting
position required for the seat belt turning loop on the
B-pillar relative to the driver's seat position on the
standard cab model. The seat belt tension reducer
may be diagnosed using conventional diagnostic tools
and methods.
DIAGNOSIS AND TESTING - SEAT BELT
TENSION REDUCER
Refer to the appropriate wiring information. The
wiring information includes wiring diagrams, proper
wire and connector repair procedures, details of wire
harness routing and retention, connector pin-out
information and location views for the various wire
harness connectors, splices and grounds.
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE SUPPLEMENTAL RESTRAINTSYSTEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, DRIVER AIRBAG,
PASSENGER AIRBAG, SEAT BELT TENSIONER,
SIDE CURTAIN AIRBAG, OR INSTRUMENT PANEL
COMPONENT DIAGNOSIS OR SERVICE. DISCON-
NECT AND ISOLATE THE BATTERY NEGATIVE
(GROUND) CABLE, THEN WAIT TWO MINUTES FOR
THE SYSTEM CAPACITOR TO DISCHARGE BEFORE
PERFORMING FURTHER DIAGNOSIS 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
AND POSSIBLE PERSONAL INJURY.
(1) Disconnect and isolate the battery negative
cable. Disconnect the body wire harness connector for
the seat belt tension reducer from the tension
reducer connector receptacle on the driver side front
outboard seat belt and retractor unit. Using an ohm-
meter, measure the resistance between the seat belt
switch sense circuit terminal pin and the fused igni-
tion switch output (run-accessory) circuit terminal
pin in the tension reducer connector receptacle on
the retractor. Resistance through the tension reducer
solenoid coil should be 53 ohms at 20É C (68É F). If
OK, go to Step 2. If not OK, replace the faulty driver
side front outboard seat belt and retractor unit.
(2) Check for continuity between the seat belt
switch sense circuit cavity of the body wire harness
connector for the seat belt tension reducer and a good
ground. There should be continuity with the driver
side front seat belt buckled, and no continuity with
the driver side front seat belt unbuckled. If OK, go to
Step 3. If not OK, repair the shorted or open seat
belt switch sense circuit between the tension reducer
and the seat belt switch as required.
(3) Reconnect the battery negative cable. Check for
battery current at the fused ignition switch output
(run-accessory) circuit of the body wire harness con-
nector for the seat belt tension reducer. There should
be battery current with the ignition switch in the On
or Accessory positions, and no battery current with
the ignition switch in any other position. If not OK,
repair the shorted or open fused ignition switch out-
put (run-accessory) circuit between the tension
reducer and the ignition switch as required.
DRRESTRAINTS 8O - 49
SEAT BELT TENSION REDUCER (Continued)
(6) Position the seat belt turning loop onto the
height adjuster on the upper inner B-pillar.
(7) Install and tighten the screw that secures the
seat belt turning loop to the height adjuster. Tighten
the screw to 40 N´m (29 ft. lbs.).
(8) Engage the lower snap features of the new trim
cover over the front outboard seat belt turning loop
and, using hand pressure, press firmly and evenly on
the top of the trim cover until it snaps into place.
SIDE CURTAIN AIRBAG
DESCRIPTION
Optional side curtain airbags are available for this
model when it is also equipped with dual front air-
bags. These airbags are passive, inflatable, Supple-
mental Restraint System (SRS) components, and
vehicles with this equipment can be readily identified
by a molded identification trim button with the ªSRS
- AIRBAGº logo located on the headliner above each
A-pillar, and above each B-pillar on quad cab models
(Fig. 47). 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
the headliner where they are each secured to one of
the roof side rails (Fig. 48). Each folded airbag cush-
ion is contained within a long extruded plastic chan-
nel that extends along the roof rail from the A-pillar
at the front of the vehicle to just behind the B-pillar
on standard cab models, and to just behind the C-pil-
lar on quad cab models. A tether 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 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. The inflator bracket and the 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 connec-
tor insulator connects directly to an integral recepta-
cle on the inflator initiator.
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 head-
liner, 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 left or right
Side Impact Airbag Control Module (SIACM) 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 con-
tains a small canister of highly compressed inert gas.
When the SIACM 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 con-
tainment disk in the inert gas canister. The inflator
Fig. 47 SRS Logo
Fig. 48 Side Curtain Airbag
1 - WIRE HARNESS CONNECTOR
2 - B-PILLAR (STD CAB) OR C-PILLAR (QUAD CAB)
3 - INFLATOR
4 - MANIFOLD
5 - ROOF SIDE RAIL
6 - A-PILLAR
7 - TETHER
8 - CHANNEL
DRRESTRAINTS 8O - 51
SEAT BELT TURNING LOOP ADJUSTER (Continued)
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, caus-
ing 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 por-
tion of the 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
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 - HAN-
DLING 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 PRO-
CEDURE - SERVICE AFTER A SUPPLEMENTAL
RESTRAINT DEPLOYMENT).
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE SUPPLEMENTAL RESTRAINT
SYSTEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, DRIVER AIRBAG,
PASSENGER AIRBAG, SEAT BELT TENSIONER,
SIDE CURTAIN AIRBAG, OR INSTRUMENT PANEL
COMPONENT DIAGNOSIS OR SERVICE. DISCON-
NECT AND ISOLATE THE BATTERY NEGATIVE
(GROUND) CABLE, THEN WAIT TWO MINUTES FOR
THE SYSTEM CAPACITOR TO DISCHARGE BEFORE
PERFORMING FURTHER DIAGNOSIS 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
AND POSSIBLE PERSONAL INJURY.
WARNING: WHEN REMOVING A DEPLOYED AIR-
BAG, RUBBER GLOVES, EYE PROTECTION, 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.WARNING: USE EXTREME CARE TO PREVENT ANY
FOREIGN MATERIAL FROM ENTERING THE SIDE
CURTAIN AIRBAG, OR BECOMING ENTRAPPED
BETWEEN THE SIDE CURTAIN AIRBAG CUSHION
AND THE HEADLINER. FAILURE TO OBSERVE THIS
WARNING COULD RESULT IN OCCUPANT INJURIES
UPON AIRBAG DEPLOYMENT.
(1) Disconnect and isolate the battery negative
cable. Wait two minutes for the system capacitor to
discharge before further service.
(2) Remove the headliner from the vehicle. (Refer
to 23 - BODY/INTERIOR/HEADLINER - REMOV-
AL).
(3) Remove the screw that secures the side curtain
airbag tether retainer to the base of the A-pillar near
the belt line (Fig. 49).
(4) Disengage the two side curtain airbag tether
plastic retainer clips from the A-pillar.
(5) Disconnect the body wire harness connector for
the side curtain airbag from the connector receptacle
at the back of the airbag inflator.
(6) Remove the four screws (standard cab) or six
screws (quad cab) that secure the side curtain airbag
inflator and manifold tube brackets to the nuts in the
roof rail.
(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 that
secure it.
Fig. 49 Side Curtain Airbag Remove/Install - Typical
1 - ROOF SIDE RAIL
2 - SPRING NUT (4 - STD CAB/6 - QUAD CAB)
3 - SCREW (4 - STD CAB/6 - QUAD CAB)
4 - CLIP (2)
5 - RIVET NUT
6 - SCREW
7 - SIDE CURTAIN AIRBAG
8 - RETAINER (3 - STD CAB/5 - QUAD CAB)
9 - WIRE HARNESS CONNECTOR
8O - 52 RESTRAINTSDR
SIDE CURTAIN AIRBAG (Continued)
(8) Remove the side curtain airbag from the vehi-
cle as a unit.
INSTALLATION
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 - HAN-
DLING 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 PRO-
CEDURE - SERVICE AFTER A SUPPLEMENTAL
RESTRAINT DEPLOYMENT).
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE SUPPLEMENTAL RESTRAINT
SYSTEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, DRIVER AIRBAG,
PASSENGER AIRBAG, SEAT BELT TENSIONER,
SIDE CURTAIN AIRBAG, OR INSTRUMENT PANEL
COMPONENT DIAGNOSIS OR SERVICE. DISCON-
NECT AND ISOLATE THE BATTERY NEGATIVE
(GROUND) CABLE, THEN WAIT TWO MINUTES FOR
THE SYSTEM CAPACITOR TO DISCHARGE BEFORE
PERFORMING FURTHER DIAGNOSIS 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
AND POSSIBLE PERSONAL INJURY.
WARNING: WHEN REMOVING A DEPLOYED AIR-
BAG, RUBBER GLOVES, EYE PROTECTION, 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.
WARNING: USE EXTREME CARE TO PREVENT ANY
FOREIGN MATERIAL FROM ENTERING THE SIDE
CURTAIN AIRBAG, OR BECOMING ENTRAPPED
BETWEEN THE SIDE CURTAIN AIRBAG CUSHION
AND THE HEADLINER. FAILURE TO OBSERVE THIS
WARNING COULD RESULT IN OCCUPANT INJURIES
UPON AIRBAG DEPLOYMENT.
(1) Position the side curtain airbag into the vehicle
as a unit.
(2) Align all three (standard cab) or five (quad cab)
plastic push-in fasteners that secure the extrudedplastic 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 (Fig. 49).
(3) Working from the rear of the vehicle to the
front, install and tighten the four screws (standard
cab) or six screws (quad cab) 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.).
(4) Reconnect the body wire harness connector for
the side curtain airbag to the connector receptacle at
the back of the airbag inflator. Be certain the connec-
tor is fully engaged and latched.
(5) Engage the two side curtain airbag tether plas-
tic retainer clips into the A-pillar.
(6) Install and tighten the screw that secures the
side curtain airbag tether retainer to the base of the
A-pillar near the belt line. Tighten the screw to 6
N´m (55 in. lbs.).
(7) Reinstall the headliner into the vehicle. (Refer
to 23 - BODY/INTERIOR/HEADLINER - INSTALLA-
TION).
(8) Do not reconnect the battery negative cable at
this time. The supplemental restraint system verifi-
cation test procedure should be performed following
service of any supplemental restraint system compo-
nent. (Refer to 8 - ELECTRICAL/RESTRAINTS -
STANDARD PROCEDURE - VERIFICATION TEST).
SIDE IMPACT AIRBAG
CONTROL MODULE
DESCRIPTION
On vehicles equipped with the optional side curtain
airbags, a Side Impact Airbag Control Module
Fig. 50 Side Impact Airbag Control Module
1 - CONNECTOR RECEPTACLE
2 - SIACM
DRRESTRAINTS 8O - 53
SIDE CURTAIN AIRBAG (Continued)
(SIACM) and its mounting bracket are secured with
four screws to the inside of each B-pillar behind
(standard cab) or above (quad cab) the front outboard
seat belt retractor, and concealed behind the B-pillar
trim (Fig. 50). Concealed within a hollow in the cen-
ter of the die cast aluminum SIACM housing is the
electronic circuitry of the SIACM which includes a
microprocessor and an electronic impact sensor.
The SIACM housing is secured to a die cast (stan-
dard cab) or stamped steel (quad cab) mounting
bracket, which is unique for the right or left side
application of this component. The SIACM should
never be removed from its mounting bracket. The
housing also receives a case ground through this
mounting bracket when it is secured to the vehicle. A
molded plastic electrical connector receptacle that
exits the top of the SIACM housing connects the unit
to the vehicle electrical system through a dedicated
take out and connector of the body wire harness.
Both the SIACM housing and its electrical connection
are sealed to protect the internal electronic circuitry
and components against moisture intrusion.
The impact sensor internal to the SIACM is cali-
brated for the specific vehicle, and is only serviced as
a unit with the SIACM. The SIACM cannot be
repaired or adjusted and, if damaged or faulty, it
must be replaced.
OPERATION
The microprocessor in the Side Impact Airbag Con-
trol Module (SIACM) contains the side curtain airbag
system logic circuits and controls all of the features
of only the side curtain airbag mounted on the same
side of the vehicle as the SIACM. The SIACM uses
On-Board Diagnostics (OBD) and can communicate
with other electronic modules in the vehicle as well
as with the DRBIIItscan tool using the Programma-
ble Communications Interface (PCI) data bus net-
work. This method of communication is used by the
SIACM to communicate with the Airbag Control
Module (ACM) and for supplemental restraint system
diagnosis and testing through the 16-way data link
connector located on the driver side lower edge of the
instrument panel. The ACM communicates with both
the left and right SIACM over the PCI data bus.
The SIACM microprocessor continuously monitors
all of the side curtain airbag electrical circuits to
determine the system readiness. If the SIACM
detects a monitored system fault, it sets an activeand stored Diagnostic Trouble Code (DTC) and sends
electronic messages to the ACM over the PCI data
bus. The ACM will respond by sending an electronic
message to the EMIC to turn on the airbag indicator,
and by storing a DTC that will indicate whether the
left or the right SIACM has stored the DTC that ini-
tiated the airbag indicator illumination. An active
fault only remains for the current ignition switch
cycle, while a stored fault causes a DTC to be stored
in memory by the SIACM. For some DTCs, if a fault
does not recur for a number of ignition cycles, the
SIACM will automatically erase the stored DTC. For
other internal faults, the stored DTC is latched for-
ever.
The SIACM receives battery current on a fused
ignition switch output (run-start) circuit through a
fuse in the Integrated Power Module (IPM). The
SIACM has a case ground through its mounting
bracket and also receives a power ground through a
ground circuit and take out of the body wire harness.
This take out has a single eyelet terminal connector
that is secured by a ground screw to the body sheet
metal. These connections allow the SIACM to be
operational whenever the ignition switch is in the
Start or On positions. An electronic impact sensor is
contained within the SIACM. The electronic impact
sensor is an accelerometer that senses the rate of
vehicle deceleration, which provides verification of
the direction and severity of an impact. A pre-pro-
grammed decision algorithm in the SIACM micropro-
cessor determines when the deceleration rate as
signaled by the impact sensor indicates a side impact
that is severe enough to require side curtain airbag
protection. When the programmed conditions are
met, the SIACM sends the proper electrical signals to
deploy the side curtain airbag.
The hard wired inputs and outputs for the SIACM
may be diagnosed and tested using conventional
diagnostic tools and procedures. However, conven-
tional diagnostic methods will not prove conclusive in
the diagnosis of the SIACM, the PCI data bus net-
work, or the electronic message inputs to and outputs
from the SIACM. The most reliable, efficient, and
accurate means to diagnose the SIACM, the PCI data
bus network, and the electronic message inputs to
and outputs from the SIACM requires the use of a
DRBIIItscan tool. Refer to the appropriate diagnos-
tic information.
8O - 54 RESTRAINTSDR
SIDE IMPACT AIRBAG CONTROL MODULE (Continued)
REMOVAL
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE SUPPLEMENTAL RESTRAINT
SYSTEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, DRIVER AIRBAG,
PASSENGER AIRBAG, SEAT BELT TENSIONER,
SIDE CURTAIN AIRBAG, OR INSTRUMENT PANEL
COMPONENT DIAGNOSIS OR SERVICE. DISCON-
NECT AND ISOLATE THE BATTERY NEGATIVE
(GROUND) CABLE, THEN WAIT TWO MINUTES FOR
THE SYSTEM CAPACITOR TO DISCHARGE BEFORE
PERFORMING FURTHER DIAGNOSIS 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
AND POSSIBLE PERSONAL INJURY.
WARNING: THE SIDE IMPACT AIRBAG CONTROL
MODULE CONTAINS THE IMPACT SENSOR, WHICH
ENABLES THE SYSTEM TO DEPLOY THE SIDE
CURTAIN AIRBAGS. NEVER STRIKE OR DROP THE
SIDE IMPACT AIRBAG CONTROL MODULE, AS IT
CAN DAMAGE THE IMPACT SENSOR OR AFFECT
ITS CALIBRATION. IF A SIDE IMPACT AIRBAG CON-
TROL MODULE IS ACCIDENTALLY DROPPED DUR-
ING SERVICE, THE MODULE MUST BE SCRAPPED
AND REPLACED WITH A NEW UNIT. FAILURE TO
OBSERVE THIS WARNING COULD RESULT IN ACCI-
DENTAL, INCOMPLETE, OR IMPROPER SIDE CUR-
TAIN AIRBAG DEPLOYMENT AND POSSIBLE
OCCUPANT INJURIES.
(1) Adjust the front seat to its most forward posi-
tion for easiest access to the lower B-pillar trim.
(2) Disconnect and isolate the battery negative
cable. Wait two minutes for the system capacitor to
discharge before further service.
(3) Remove the front outboard seat belt and retrac-
tor from the inside of the B-pillar. (Refer to 8 -
ELECTRICAL/RESTRAINTS/FRONT OUTBOARD
SEAT BELT & RETRACTOR - REMOVAL - STAN-
DARD CAB).
(4) Remove the four screws that secure the Side
Impact Airbag Control Module (SIACM) mounting
bracket to the inside of the B-pillar (Fig. 51).
(5) Reach through the retractor mounting hole in
the inner B-pillar to access and disengage the two
plastic push-in fasteners that secure the SIACM to
the inside of the B-pillar.(6) Pull the SIACM and mounting bracket out
through the retractor mounting hole far enough to
access and disconnect the body wire harness connec-
tor for the SIACM from the module connector recep-
tacle.
(7) Remove the SIACM and its mounting bracket
from the B-pillar as a unit.
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE SUPPLEMENTAL RESTRAINT
SYSTEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, DRIVER AIRBAG,
PASSENGER AIRBAG, SEAT BELT TENSIONER,
SIDE CURTAIN AIRBAG, OR INSTRUMENT PANEL
COMPONENT DIAGNOSIS OR SERVICE. DISCON-
NECT AND ISOLATE THE BATTERY NEGATIVE
(GROUND) CABLE, THEN WAIT TWO MINUTES FOR
THE SYSTEM CAPACITOR TO DISCHARGE BEFORE
PERFORMING FURTHER DIAGNOSIS 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
AND POSSIBLE PERSONAL INJURY.
Fig. 51 Side Impact Airbag Control Module
Remove/Install - Std Cab
1 - B-PILLAR
2 - SCREW (4)
3 - FASTENER (2)
4 - BRACKET
5 - SIACM
6 - WIRE HARNESS CONNECTOR
DRRESTRAINTS 8O - 55
SIDE IMPACT AIRBAG CONTROL MODULE (Continued)
WARNING: THE SIDE IMPACT AIRBAG CONTROL
MODULE CONTAINS THE IMPACT SENSOR, WHICH
ENABLES THE SYSTEM TO DEPLOY THE SIDE
CURTAIN AIRBAGS. NEVER STRIKE OR DROP THE
SIDE IMPACT AIRBAG CONTROL MODULE, AS IT
CAN DAMAGE THE IMPACT SENSOR OR AFFECT
ITS CALIBRATION. IF A SIDE IMPACT AIRBAG CON-
TROL MODULE IS ACCIDENTALLY DROPPED DUR-
ING SERVICE, THE MODULE MUST BE SCRAPPED
AND REPLACED WITH A NEW UNIT. FAILURE TO
OBSERVE THIS WARNING COULD RESULT IN ACCI-
DENTAL, INCOMPLETE, OR IMPROPER SIDE CUR-
TAIN AIRBAG DEPLOYMENT AND POSSIBLE
OCCUPANT INJURIES.
(1) Adjust the front seat to its most forward posi-
tion for easiest access to the lower B-pillar trim.
(2) Disconnect and isolate the battery negative
cable. Wait two minutes for the system capacitor to
discharge before further service.
(3) Remove the front outboard seat belt and retrac-
tor from the inside of the B-pillar. (Refer to 8 -
ELECTRICAL/RESTRAINTS/FRONT OUTBOARD
SEAT BELT & RETRACTOR - REMOVAL - QUAD
CAB).
(4) Remove the four screws that secure the Side
Impact Airbag Control Module (SIACM) mounting
bracket to the inside of the B-pillar (Fig. 52).(5) Reach through the retractor mounting hole in
the inner B-pillar to access the SIACM and lift it
upward far enough to disengage the hook on the
mounting bracket from the slot on the inner B-pillar.
(6) Pull the SIACM and mounting bracket out
through the retractor mounting hole far enough to
access and disconnect the body wire harness connec-
tor for the SIACM from the module connector recep-
tacle.
(7) Remove the SIACM and its mounting bracket
from the B-pillar as a unit.
INSTALLATION
INSTALLATION
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE SUPPLEMENTAL RESTRAINT
SYSTEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, DRIVER AIRBAG,
PASSENGER AIRBAG, SEAT BELT TENSIONER,
SIDE CURTAIN AIRBAG, OR INSTRUMENT PANEL
COMPONENT DIAGNOSIS OR SERVICE. DISCON-
NECT AND ISOLATE THE BATTERY NEGATIVE
(GROUND) CABLE, THEN WAIT TWO MINUTES FOR
THE SYSTEM CAPACITOR TO DISCHARGE BEFORE
PERFORMING FURTHER DIAGNOSIS 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
AND POSSIBLE PERSONAL INJURY.
WARNING: THE SIDE IMPACT AIRBAG CONTROL
MODULE CONTAINS THE IMPACT SENSOR, WHICH
ENABLES THE SYSTEM TO DEPLOY THE SIDE
CURTAIN AIRBAGS. NEVER STRIKE OR DROP THE
SIDE IMPACT AIRBAG CONTROL MODULE, AS IT
CAN DAMAGE THE IMPACT SENSOR OR AFFECT
ITS CALIBRATION. IF A SIDE IMPACT AIRBAG CON-
TROL MODULE IS ACCIDENTALLY DROPPED DUR-
ING SERVICE, THE MODULE MUST BE SCRAPPED
AND REPLACED WITH A NEW UNIT. FAILURE TO
OBSERVE THIS WARNING COULD RESULT IN ACCI-
DENTAL, INCOMPLETE, OR IMPROPER SIDE CUR-
TAIN AIRBAG DEPLOYMENT AND POSSIBLE
OCCUPANT INJURIES.
(1) Position the Side Impact Airbag Control Mod-
ule (SIACM) and its mounting bracket to the B-pillar
as a unit (Fig. 51).
(2) Reconnect the body wire harness connector for
the SIACM to the module connector receptacle.
(3) Reach through the retractor mounting hole in
the inner B-pillar to position and engage the two
Fig. 52 Side Impact Airbag Control Module
Remove/Install - Quad Cab
1 - B-PILLAR
2 - WIRE HARNESS CONNECTOR
3 - SCREW (4)
4 - HOOK
5 - BRACKET
6 - SIACM
7 - SLOT
8O - 56 RESTRAINTSDR
SIDE IMPACT AIRBAG CONTROL MODULE (Continued)