1998 DODGE RAM 1500 4 wheel drive

(9) Remove the screw that secures the seat belt
web guide to the inner B-pillar near the belt line.
(10) Remove the seat belt web guide from the
inner B-pillar.
(11) Disengage the seat belt tensioner pigtail wire
retainer from the hole in the inner B-pillar sheet
metal.
(12) Disconnect the yellow seat belt tensioner pig-
tail wire connector from the body wire harness take
out and connector for the tensioner.
(13) Remove the screw that secures the lower
retractor bracket to the lower inner B-pillar below
the retractor mounting hole.
(14) Disengage the hooks on the upper retractor
bracket from the slots in the lower inner B-pillar
above the retractor mounting hole.
(15) Remove the front outboard seat belt and
retractor from the retractor mounting hole in the
lower inner B-pillar.
INSTALLATION
INSTALLATION - STANDARD CAB
The following procedure is for replacement of a
faulty or damaged front outboard seat belt and
retractor unit, which includes a seat belt tensioner
for this model. (Refer to 8 - ELECTRICAL/RE-
STRAINTS/SEAT BELT TENSIONER - DESCRIP-
TION). The only component of this seat belt and
retractor unit that is available for individual service
replacement is the plastic web stop button that pre-
vents the latch plate from falling to the floor while in
the stored position. Refer to the instructions supplied
with the service kit for the proper web stop button
replacement procedures.
The seat belt retractor on the driver's side of stan-
dard cab models only also includes a tension reducer.
(Refer to 8 - ELECTRICAL/RESTRAINTS/TENSION
REDUCER - DESCRIPTION). The seat belt retractor
on the passenger's side of all models includes a swit-
chable automatic locking mechanism. (Refer to 8 -
ELECTRICAL/RESTRAINTS/AUTOMATIC LOCK-
ING RETRACTOR - DESCRIPTION).
If the seat belt or retractor is faulty or damaged,
but the seat belt tensioner is not deployed, review
the recommended procedures for handling non-de-
ployed supplemental restraints. (Refer to 8 - ELEC-
TRICAL/RESTRAINTS - STANDARD PROCEDURE
- HANDLING NON-DEPLOYED SUPPLEMENTAL
RESTRAINTS). If the seat belt tensioner has been
deployed, review the recommended procedures for
service after a supplemental restraint deployment
before removing the front outboard seat belt and
retractor from the vehicle. (Refer to 8 - ELECTRI-
CAL/RESTRAINTS - STANDARD PROCEDURE -SERVICE AFTER A SUPPLEMENTAL RESTRAINT
DEPLOYMENT).
WARNING: TO AVOID PERSONAL INJURY OR
DEATH, ON VEHICLES EQUIPPED WITH AIRBAGS,
DISABLE THE SUPPLEMENTAL RESTRAINT SYS-
TEM 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 NEGA-
TIVE (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 DIS-
ABLE THE SUPPLEMENTAL RESTRAINT SYSTEM.
FAILURE TO TAKE THE PROPER PRECAUTIONS
COULD RESULT IN ACCIDENTAL AIRBAG DEPLOY-
MENT.
WARNING: TO AVOID PERSONAL INJURY OR
DEATH, DURING AND FOLLOWING ANY SEAT BELT
OR CHILD RESTRAINT ANCHOR SERVICE, CARE-
FULLY INSPECT ALL SEAT BELTS, BUCKLES,
MOUNTING HARDWARE, RETRACTORS, TETHER
STRAPS, AND ANCHORS FOR PROPER INSTALLA-
TION, OPERATION, OR DAMAGE. REPLACE ANY
BELT THAT IS CUT, FRAYED, OR TORN.
STRAIGHTEN ANY BELT THAT IS TWISTED.
TIGHTEN ANY LOOSE FASTENERS. REPLACE ANY
BELT THAT HAS A DAMAGED OR INOPERATIVE
BUCKLE OR RETRACTOR. REPLACE ANY BELT
THAT HAS A BENT OR DAMAGED LATCH PLATE
OR ANCHOR PLATE. REPLACE ANY CHILD
RESTRAINT ANCHOR OR THE UNIT TO WHICH THE
ANCHOR IS INTEGRAL THAT HAS BEEN BENT OR
DAMAGED. NEVER ATTEMPT TO REPAIR A SEAT
BELT OR CHILD RESTRAINT COMPONENT.
ALWAYS REPLACE DAMAGED OR FAULTY SEAT
BELT AND CHILD RESTRAINT COMPONENTS WITH
THE CORRECT, NEW AND UNUSED REPLACEMENT
PARTS LISTED IN THE DAIMLERCHRYSLER MOPAR
PARTS CATALOG.
(1) Position the front outboard seat belt and
retractor to the retractor mounting hole in the lower
inner B-pillar (Fig. 31).
(2) Engage the hooks on the upper retractor
bracket into the slots in the lower inner B-pillar
above the retractor mounting hole.
(3) Install and tighten the screw that secures the
lower retractor bracket to the lower inner B-pillar
below the retractor mounting hole. Tighten the screw
to 40 N´m (29 ft. lbs.).
DRRESTRAINTS 8O - 35
FRONT OUTBOARD SEAT BELT & RETRACTOR (Continued)

(4) Reconnect the yellow seat belt tensioner pigtail
wire connector to the body wire harness take out and
connector for the tensioner.
(5) Engage the seat belt tensioner pigtail wire
retainer into the hole in the inner B-pillar sheet
metal.
(6) On the driver side only, reconnect the body
wire harness take out and white connector to the
seat belt tension reducer connector receptacle near
the bottom of the retractor.
(7) Position the seat belt web guide to its mount-
ing location on the inner B-pillar near the belt line.
(8) Install and tighten the screw that secures the
seat belt web guide to the inner B-pillar. Tighten the
screw to 2 N´m (20 in. lbs.).
(9) Reinstall the upper and lower trim onto the
inner B-pillar. (Refer to 23 - BODY/INTERIOR/B-
PILLAR UPPER TRIM - INSTALLATION) and
(Refer to 23 - BODY/INTERIOR/B-PILLAR LOWER
TRIM - INSTALLATION).
(10) Position the seat belt turning loop onto the
height adjuster on the upper inner B-pillar.
(11) 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.).
(12) 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.
(13) Position the lower seat belt anchor to the
lower inner B-pillar.
(14) Install and tighten the screw that secures the
lower seat belt anchor to the B-pillar. Tighten the
screw to 40 N´m (29 ft. lbs.).
(15) 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).
(16) Move the front seat back to its rearward posi-
tion.INSTALLATION - QUAD CAB
The following procedure is for replacement of a
faulty or damaged front outboard seat belt and
retractor unit, which includes a seat belt tensioner
for this model. (Refer to 8 - ELECTRICAL/RE-
STRAINTS/SEAT BELT TENSIONER - DESCRIP-
TION). The only component of this seat belt and
retractor unit that is available for individual service
replacement is the plastic web stop button that pre-
vents the latch plate from falling to the floor while in
the stored position. Refer to the instructions supplied
with the service kit for the proper web stop button
replacement procedures.
The seat belt retractor on the passenger's side of
all models includes a switchable automatic locking
mechanism. (Refer to 8 - ELECTRICAL/RE-
STRAINTS/AUTOMATIC LOCKING RETRACTOR -
DESCRIPTION).
If the seat belt or retractor is faulty or damaged,
but the seat belt tensioner is not deployed, review
the recommended procedures for handling non-de-
ployed supplemental restraints. (Refer to 8 - ELEC-
TRICAL/RESTRAINTS - STANDARD PROCEDURE
- HANDLING NON-DEPLOYED SUPPLEMENTAL
RESTRAINTS). If the seat belt tensioner has been
deployed, review the recommended procedures for
service after a supplemental restraint deployment
before removing the front outboard seat belt and
retractor from the vehicle. (Refer to 8 - ELECTRI-
CAL/RESTRAINTS - STANDARD PROCEDURE -
SERVICE AFTER A SUPPLEMENTAL RESTRAINT
DEPLOYMENT).
WARNING: TO AVOID PERSONAL INJURY OR
DEATH, ON VEHICLES EQUIPPED WITH AIRBAGS,
DISABLE THE SUPPLEMENTAL RESTRAINT SYS-
TEM 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 NEGA-
TIVE (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 DIS-
ABLE THE SUPPLEMENTAL RESTRAINT SYSTEM.
FAILURE TO TAKE THE PROPER PRECAUTIONS
COULD RESULT IN ACCIDENTAL AIRBAG DEPLOY-
MENT.
8O - 36 RESTRAINTSDR
FRONT OUTBOARD SEAT BELT & RETRACTOR (Continued)

The passenger airbag on/off switch housing is con-
structed of molded plastic and has three integral
mounting tabs. These mounting tabs are used to
secure the switch to the back of the molded plastic
switch face plate with three small screws. The
molded plastic face plate also has three integral
mounting tabs that are used to secure the switch and
face plate unit to the instrument panel center bezel
with three additional screws. A molded plastic con-
nector receptacle on the back of the switch housing
connects the switch to the vehicle electrical system
through a dedicated take out and connector of the
instrument panel wire harness. The molded plastic
harness connector insulator is keyed and latched to
ensure proper and secure switch electrical connec-
tions. The passenger airbag on/off switch cannot be
adjusted or repaired and, if faulty or damaged, the
switch must be replaced.
OPERATION
The passenger airbag on/off switch allows the cus-
tomer to turn the passenger airbag function On or
Off to accommodate certain uses of the right front
seating position where airbag protection may not be
desired. See the owner's manual in the vehicle glove
box for specific recommendations on when to enable
or disable the passenger airbag. The Off indicator of
the switch will be illuminated whenever the switch is
turned to the Off position and the ignition switch is
in the On position.
The ignition key is the only key or object that
should ever be inserted into the key cylinder actuator
of the switch. The on/off switch requires only a par-
tial key insertion to fully depress a spring-loaded
locking plunger. The spring-loaded locking plunger
prevents the user from leaving the key in the switch.
The key will be automatically ejected when force is
not applied. To actuate the passenger airbag on/off
switch, insert the ignition key into the switch key
actuator far enough to fully depress the plunger, then
rotate the actuator to the desired switch position.
When the switch key actuator is rotated to its clock-
wise stop (the key actuator slot will be aligned with
the Off indicator), the Off indicator is illuminated
and the passenger airbag is disabled. When the
switch is rotated to its counterclockwise stop (the key
actuator slot will be in a vertical position), the Off
indicator will be extinguished and the passenger air-
bag is enabled.The passenger airbag on/off switch connects one of
two internal resistors in series between the passen-
ger airbag mux switch sense and passenger airbag
mux switch return circuits of the Airbag Control
Module (ACM). The ACM continually monitors the
resistance in these circuits to determine the switch
position that has been selected. When the switch is
in the Off position, the ACM provides a ground input
to the switch through the passenger airbag indicator
driver circuit, which energizes the Light-Emitting
Diode (LED) that illuminates the Off indicator of the
switch.
The ACM will also illuminate the Off indicator of
the switch for about seven seconds each time the
ignition switch is turned to the On position as a bulb
test. The ACM will store a Diagnostic Trouble Code
(DTC) for any fault it detects in the passenger airbag
on/off switch or Off indicator circuits, and will illumi-
nate the airbag indicator in the instrument cluster if
a fault is detected. For proper diagnosis of the pas-
senger airbag on/off switch or the ACM, a DRBIIIt
scan tool is required. Refer to the appropriate diag-
nostic information.
REMOVAL
WARNING: TO AVOID PERSONAL INJURY OR
DEATH, ON VEHICLES EQUIPPED WITH AIRBAGS,
DISABLE THE SUPPLEMENTAL RESTRAINT SYS-
TEM 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 NEGA-
TIVE (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 DIS-
ABLE THE SUPPLEMENTAL RESTRAINT SYSTEM.
FAILURE TO TAKE THE PROPER PRECAUTIONS
COULD RESULT IN ACCIDENTAL AIRBAG DEPLOY-
MENT.
(1) Disconnect and isolate the battery negative
cable. Wait two minutes for the system capacitor to
discharge before further service.
(2) Remove the center bezel from the instrument
panel. (Refer to 23 - BODY/INSTRUMENT PANEL/
INSTRUMENT PANEL CENTER BEZEL -
REMOVAL).
(3) From the back of the center bezel, remove the
three screws that secure the passenger airbag on/off
switch and face plate unit to the back of the bezel
(Fig. 40).
(4) Remove the passenger airbag on/off switch and
face plate from the center bezel as a unit.
DRRESTRAINTS 8O - 43
PASSENGER AIRBAG ON/OFF SWITCH (Continued)

INSTALLATION
WARNING: TO AVOID PERSONAL INJURY OR
DEATH, ON VEHICLES EQUIPPED WITH AIRBAGS,
DISABLE THE SUPPLEMENTAL RESTRAINT SYS-
TEM 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 NEGA-
TIVE (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 DIS-
ABLE THE SUPPLEMENTAL RESTRAINT SYSTEM.
FAILURE TO TAKE THE PROPER PRECAUTIONS
COULD RESULT IN ACCIDENTAL AIRBAG DEPLOY-
MENT.
(1) Position the passenger airbag on/off switch and
face plate unit to the back of the center bezel (Fig.
40).
(2) Install and tighten the three screws that secure
the passenger airbag on/off switch face plate to the
back of the center bezel. Tighten the screws to 2 N´m
(17 in. lbs.).
(3) Reinstall the center bezel onto the instrument
panel. (Refer to 23 - BODY/INSTRUMENT PANEL/
INSTRUMENT PANEL CENTER BEZEL - INSTAL-
LATION).
(4) 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).
REAR CENTER SEAT BELT &
RETRACTOR
REMOVAL
The rear center seat belt retractor is secured with
a single screw to a mounting bracket that includes
the unique black, keyed center seat belt lower anchor
buckle and the right outboard occupant buckle, but
can be removed from the mounting bracket and is
serviced separately from the two buckles. The center
anchor buckle and the right outboard occupant
buckle are serviced as a unit with their mounting
bracket. (Refer to 8 - ELECTRICAL/RESTRAINTS/
REAR SEAT BELT BUCKLE - REMOVAL - CEN-
TER ANCHOR & RIGHT OUTBOARD).
WARNING: TO AVOID PERSONAL INJURY OR
DEATH, DURING AND FOLLOWING ANY SEAT BELT
OR CHILD RESTRAINT ANCHOR SERVICE, CARE-
FULLY INSPECT ALL SEAT BELTS, BUCKLES,
MOUNTING HARDWARE, RETRACTORS, TETHER
STRAPS, AND ANCHORS FOR PROPER INSTALLA-
TION, OPERATION, OR DAMAGE. REPLACE ANY
BELT THAT IS CUT, FRAYED, OR TORN.
STRAIGHTEN ANY BELT THAT IS TWISTED.
TIGHTEN ANY LOOSE FASTENERS. REPLACE ANY
BELT THAT HAS A DAMAGED OR INOPERATIVE
BUCKLE OR RETRACTOR. REPLACE ANY BELT
THAT HAS A BENT OR DAMAGED LATCH PLATE
OR ANCHOR PLATE. REPLACE ANY CHILD
RESTRAINT ANCHOR OR THE UNIT TO WHICH THE
ANCHOR IS INTEGRAL THAT HAS BEEN BENT OR
DAMAGED. NEVER ATTEMPT TO REPAIR A SEAT
BELT OR CHILD RESTRAINT COMPONENT.
ALWAYS REPLACE DAMAGED OR FAULTY SEAT
BELT AND CHILD RESTRAINT COMPONENTS WITH
THE CORRECT, NEW AND UNUSED REPLACEMENT
PARTS LISTED IN THE DAIMLERCHRYSLER MOPAR
PARTS CATALOG.
(1) Reach between the rear seat cushion and the
rear seat back to access and unbuckle the center seat
belt lower anchor latch plate from the unique black,
keyed lower anchor buckle. Use an ignition key or a
small screwdriver to depress the small white release
button on the anchor buckle.
(2) Remove the rear seat from the vehicle. On
models with the optional 60/40 split rear bench, only
the 60 percent section (right side) of the rear seat
must be removed. (Refer to 23 - BODY/SEATS/SEAT
- REAR - REMOVAL).
Fig. 40 Passenger Airbag On/Off Switch Remove/
Install
1 - CENTER BEZEL
2 - SCREW (3)
3 - SWITCH & PLATE UNIT
8O - 44 RESTRAINTSDR
PASSENGER AIRBAG ON/OFF SWITCH (Continued)

WARNING: TO AVOID PERSONAL INJURY OR
DEATH, ON VEHICLES EQUIPPED WITH AIRBAGS,
DISABLE THE SUPPLEMENTAL RESTRAINT SYS-
TEM 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 NEGA-
TIVE (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 DIS-
ABLE THE SUPPLEMENTAL RESTRAINT SYSTEM.
FAILURE TO TAKE THE PROPER PRECAUTIONS
COULD RESULT IN ACCIDENTAL AIRBAG DEPLOY-
MENT.
(1) Disconnect and isolate the battery negative
cable. Disconnect the seat belt switch pigtail wire
connector from the seat wire harness connector for
the seat belt switch on the inboard side of the driver
side front seat forward of the seat belt buckle-half
anchor. Check for continuity between the seat belt
switch sense circuit and the ground circuit cavities of
the seat belt switch pigtail wire connector. There
should be continuity with the seat belt buckled, and
no continuity with the seat belt unbuckled. If OK, go
to Step 2. If not OK, replace the faulty front seat belt
buckle-half assembly.
(2) Check for continuity between the ground cir-
cuit cavity in the seat wire harness connector for the
seat belt switch and a good ground. There should be
continuity. If OK, go to Step 3. If not OK, repair the
open ground circuit to ground (G301) as required.
(3) Remove the instrument cluster from the instru-
ment panel. Check for continuity between the seat
belt switch sense circuit cavity of the seat wire har-
ness connector for the seat belt switch and a good
ground. There should be no continuity. If OK, go to
Step 4. If not OK, repair the shorted seat belt switch
sense circuit between the seat belt switch and the
instrument cluster as required.
(4) Check for continuity between the seat belt
switch sense circuit cavities of the seat wire harness
connector for the seat belt switch and the instrument
panel wire harness connector (Connector C2) for the
instrument cluster. There should be continuity. If
OK, test and replace the faulty instrument cluster as
required. (Refer to 8 - ELECTRICAL/INSTRUMENT
CLUSTER - DIAGNOSIS AND TESTING). If not OK,
repair the open seat belt switch sense circuit between
the seat belt switch and the instrument cluster as
required.SEAT BELT TENSIONER
DESCRIPTION
Front outboard seating position seat belt tension-
ers supplement the driver and passenger airbags for
all versions of this model (Fig. 48). The seat belt ten-
sioner is integral to the front outboard seat belt and
retractor units, which are secured to the inner B-pil-
lar on the right and left sides of the vehicle. The
retractor is concealed beneath the molded plastic
inner B-pillar trim. The seat belt tensioner consists
primarily of a die cast aluminum tensioner housing
or chamber, a mechanical clutch unit, a tape-like
metal strip, a pair of cutters, a pyrotechnically acti-
vated gas generator, and a short pigtail wire. All of
these components are located on one side of the
retractor spool on the outside of the retractor hous-
ing. The seat belt tensioners are controlled by the
Airbag Control Module (ACM) and are connected to
the vehicle electrical system through a dedicated
take out of the body wire harness by a keyed and
latching molded plastic connector insulator to ensure
a secure connection.
The seat belt tensioners 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 tensioners are
not intended for reuse and must be replaced follow-
ing any front airbag deployment. A locked retractor
that will not allow the seat belt webbing to be
Fig. 48 Seat Belt Tensioner
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
7 - RETRACTOR LOCKING MECHANISM COVER
8O - 52 RESTRAINTSDR
SEAT BELT SWITCH (Continued)

retracted or extracted is a sure indication that the
seat belt tensioner has been deployed and requires
replacement. (Refer to 8 - ELECTRICAL/RE-
STRAINTS/FRONT OUTBOARD SEAT BELT &
RETRACTOR - REMOVAL).
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 will
illuminate 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. 49). 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
outboard seat belt and retractor unit must be
replaced. (Refer to 8 - ELECTRICAL/RESTRAINTS/
FRONT OUTBOARD SEAT BELT & RETRACTOR -
REMOVAL).
Fig. 49 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
DRRESTRAINTS 8O - 53
SEAT BELT TENSIONER (Continued)

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: TO AVOID PERSONAL INJURY OR
DEATH, ON VEHICLES EQUIPPED WITH AIRBAGS,
DISABLE THE SUPPLEMENTAL RESTRAINT SYS-
TEM 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 NEGA-
TIVE (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 DIS-
ABLE THE SUPPLEMENTAL RESTRAINT SYSTEM.
FAILURE TO TAKE THE PROPER PRECAUTIONS
COULD RESULT IN ACCIDENTAL AIRBAG DEPLOY-
MENT.(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.
8O - 54 RESTRAINTSDR
SEAT BELT TENSION REDUCER (Continued)

5.9L Diesel With Manual Trans.
The speed control system is fully electronically con-
trolled by the Engine Control Module (ECM).A
cable and a vacuum controlled servo are not
used if the vehicle is equipped with a manual
transmission and a diesel engine. This is a ser-
vo-less system.The controls consist of two steering
wheel mounted switches. The switches are labeled:
ON/OFF, RES/ACCEL, SET, COAST, and CANCEL.
The system is designed to operate at speeds above
30 mph (50 km/h).
WARNING: THE USE OF SPEED CONTROL IS NOT
RECOMMENDED WHEN DRIVING CONDITIONS DO
NOT PERMIT MAINTAINING A CONSTANT SPEED,
SUCH AS IN HEAVY TRAFFIC OR ON ROADS THAT
ARE WINDING, ICY, SNOW COVERED, OR SLIP-
PERY.
OPERATION
When speed control is selected by depressing the
ON switch, the PCM (the ECM with a diesel engine)
allows a set speed to be stored in its RAM for speed
control. To store a set speed, depress the SET switch
while the vehicle is moving at a speed between 35
and 85 mph. In order for the speed control to engage,
the brakes cannot be applied, nor can the gear selec-
tor be indicating the transmission is in Park or Neu-
tral.
The speed control can be disengaged manually by:
²Stepping on the brake pedal
²Depressing the OFF switch
²Depressing the CANCEL switch.
²Depressing the clutch pedal (if equipped).
NOTE: Depressing the OFF switch or turning off the
ignition switch will erase the set speed stored in
the PCM (the ECM with a diesel engine).
For added safety, the speed control system is pro-
grammed to disengage for any of the following condi-
tions:
²An indication of Park or Neutral
²A rapid increase rpm (indicates that the clutch
has been disengaged)
²Excessive engine rpm (indicates that the trans-
mission may be in a low gear)
²The speed signal increases at a rate of 10 mph
per second (indicates that the coefficient of friction
between the road surface and tires is extremely low)
²The speed signal decreases at a rate of 10 mph
per second (indicates that the vehicle may have
decelerated at an extremely high rate)Once the speed control has been disengaged,
depressing the RES/ACCEL switch (when speed is
greater than 30 mph) restores the vehicle to the tar-
get speed that was stored in the PCM (the ECM with
a diesel engine).
While the speed control is engaged, the driver can
increase the vehicle speed by depressing the RES/AC-
CEL switch. The new target speed is stored in the
PCM (the ECM with a diesel engine) when the RES/
ACCEL is released. The PCM (the ECM with a diesel
engine) also has a9tap-up9feature in which vehicle
speed increases at a rate of approximately 2 mph for
each momentary switch activation of the RES/AC-
CEL switch.
A ªtap downº feature is used to decelerate without
disengaging the speed control system. To decelerate
from an existing recorded target speed, momentarily
depress the COAST switch. For each switch activa-
tion, speed will be lowered approximately 1 mph.DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - VACUUM SUPPLY
TEST
3.7L / 4.7L Gas Powered Engines
3.7L/4.7L gas powered engines: actual engine vac-
uum, a vacuum reservoir, a one-way check valve and
vacuum lines are used to supply vacuum to the speed
control servo.
(1) Disconnect vacuum hose at speed control servo
and install a vacuum gauge into the disconnected
hose.
(2) Start engine and observe gauge at idle. Vac-
uum gauge should read at least ten inches of mer-
cury.
(3) If vacuum is less than ten inches of mercury,
determine source of leak. Check vacuum line to
engine for leaks. Also check actual engine intake
manifold vacuum. If manifold vacuum does not meet
this requirement, check for poor engine performance
and repair as necessary.
(4) If vacuum line to engine is not leaking, check
for leak at vacuum reservoir. To locate and gain
access to reservoir, refer to Vacuum Reservoir Remov-
al/Installation in this group. Disconnect vacuum line
at reservoir and connect a hand-operated vacuum
pump to reservoir fitting. Apply vacuum. Reservoir
vacuum should not bleed off. If vacuum is being lost,
replace reservoir.
8P - 2 SPEED CONTROLDR
SPEED CONTROL (Continued)