Dodge Nitro. Manual — part 252

unit must be replaced. The retractor tensioners are not intended for reuse and must be replaced following any
front airbag 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 tensioner has been deployed and requires replacement. See REMOVAL.

BUCKLE TENSIONER

Fig. 82: Identifying Molded Plastic Scabbard, Buckle, Pigtail Harnesses, Steel Cylinder Tube & Bracket
Courtesy of CHRYSLER LLC

Seat belt buckle tensioners supplement the dual front and side curtain airbags for all versions of this vehicle.
These tensioners are integral to the front seat belt buckle units, which are secured by a large screw to the outside
of the inboard seat cushion frames of the right and left front seats. The buckle tensioner consists primarily of a
buckle (2), a molded plastic scabbard (1), a cable and piston, a cable guide and bracket (5), a steel cylinder tube
(4), and a small pyrotechnically activated gas generator.

The buckle tensioners are controlled by the Occupant Restraint Controller (ORC) and are connected to the
vehicle electrical system through a dedicated take out of the seat wire harness by a keyed and latching yellow
molded plastic connector insulator to ensure a secure connection. The buckle tensioner connector for the driver
side is shared by two pigtail harnesses (3): one two-wire squib pigtail and a second two-wire pigtail for the
integral seat belt switch.

The buckle tensioners cannot be repaired and, if ineffective or damaged, the entire front seat belt buckle unit
must be replaced. If the front airbags have been deployed, the buckle tensioners have also been deployed. The
buckle tensioners are not intended for reuse and must be replaced following any front airbag deployment. See
REMOVAL.

OPERATION

SEAT BELT TENSIONER

The seat belt retractor tensioners and buckle tensioners are deployed by a signal generated by the Occupant
Restraint Controller (ORC) through the driver or passenger seat belt tensioner line 1 and line 2 (or squib)
circuits. When the ORC sends the proper electrical signal to the tensioners, the electrical energy generates

2007 Dodge Nitro R/T

2007 RESTRAINTS Service Information - Nitro

enough heat to initiate a small pyrotechnic gas generator.

On the retractor tensioner, the gas generator is installed in one end of the tubular metal piston housing, which
contains a piston and a small rack gear. As the gas expands, it pushes the piston and the rack gear through the
tube. The rack gear engages a pinion gear that drives a gear set in the tensioner housing, which rotates the seat
belt retractor spool causing the slack to be removed from the front seat belts.

On the buckle tensioner, the gas generator is installed in one end of the tubular metal piston housing, which
contains a piston secured to one end of a cable. The cable is routed around an integral guide to the buckle,
which is secured to the opposite end of the cable. As the gas expands, it pushes the piston and the cable through
the tube and pulls the buckle downward, causing the slack to be removed from the front seat belts.

Removing excess slack from the front seat belts not only keeps the occupants properly positioned for an airbag
deployment following a frontal impact of the vehicle, but also helps to reduce injuries that the occupants of the
front seat might experience in these situations as a result of a harmful contact with the steering wheel, steering
column, instrument panel or windshield. Also, the seat belt retractor has a torsion bar mechanism that is
designed to deform in order to control the loading being applied to the occupants by the seat belts during a
frontal impact, further reducing the potential for occupant injuries.

The ORC monitors the condition of the seat belt tensioners through circuit resistance, and will illuminate the
airbag indicator in the Electro Mechanical Instrument Cluster (EMIC) and store a Diagnostic Trouble Code
(DTC) for any fault that is detected. Proper diagnosis of the seat belt tensioner gas generator and squib circuits
requires the use of a diagnostic scan tool. Refer to the appropriate diagnostic information.

SEAT BELT TURNING LOOP ADJUSTER

REMOVAL

SEAT BELT TURNING LOOP ADJUSTER

WARNING:

To avoid serious or fatal injury during and following any seat belt or child
restraint anchor service, carefully inspect all seat belts, buckles,
mounting hardware, retractors, tether straps, and anchors for proper
installation, 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 ineffective 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 ineffective
seat belt and child restraint components with the correct, new and
unused replacement parts .

2007 Dodge Nitro R/T

2007 RESTRAINTS Service Information - Nitro

Fig. 83: Identifying B-Pillar, Height Adjuster, Seat Belt Turning Loop & Upper Trim
Courtesy of CHRYSLER LLC

1. Remove the upper trim (4) from the inside of the B-pillar (1). Refer to REMOVAL .

2. Remove the screw that secures the seat belt turning loop (3) to the height adjuster (2) on the upper B-

pillar.

3. Remove the seat belt turning loop from the height adjuster.

4. Remove the screw that secures the upper end of the seat belt turning loop adjuster to the upper B-pillar.

5. Pull the turning loop adjuster upward and away from the B-pillar far enough to disengage the tabs on the

lower end of the adjuster from the keyed holes in the B-pillar.

6. Remove the seat belt turning loop adjuster from the B-pillar.

INSTALLATION

SEAT BELT TURNING LOOP ADJUSTER

WARNING:

To avoid serious or fatal injury during and following any seat belt or child
restraint anchor service, carefully inspect all seat belts, buckles,
mounting hardware, retractors, tether straps, and anchors for proper
installation, 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 ineffective 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 ineffective
seat belt and child restraint components with the correct, new and
unused replacement parts .

2007 Dodge Nitro R/T

2007 RESTRAINTS Service Information - Nitro

Fig. 84: Identifying B-Pillar, Height Adjuster, Seat Belt Turning Loop & Upper Trim
Courtesy of CHRYSLER LLC

1. Position the seat belt turning loop adjuster (2) to the inner B-pillar (1).

2. Engage the tabs on the lower end of the adjuster into the keyed holes in the B-pillar.

3. Position the upper end of the turning loop adjuster against the B-pillar.

4. Install and tighten the screw that secures the seat belt turning loop adjuster to the upper B-pillar. Tighten

the screw to 44.5 N.m (33 ft. lbs.).

5. Position the seat belt turning loop (3) onto the height adjuster on the upper B-pillar. Be certain that the

seat belt webbing (5) between the retractor and the turning loop, and between the turning loop and the
lower anchor is not twisted.

6. Install and tighten the screw that secures the seat belt turning loop to the height adjuster. Tighten the

screw to 44.5 N.m (33 ft. lbs.).

7. Reinstall the upper trim (4) onto the inside of the B-pillar. Refer to INSTALLATION .

SEAT WEIGHT SENSOR

DESCRIPTION

SEAT WEIGHT SENSOR

2007 Dodge Nitro R/T

2007 RESTRAINTS Service Information - Nitro