Jeep Liberty KJ. Manual - part 250

REAR CENTER

WARNING: To avoid personal injury or death, 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 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 rear center seat belt and retractor unit

onto the seat back panel (1).

2. Install and tighten the screw (2) that secures the

retractor to the rear seat back panel. Tighten the
screw to 27 N·m (20 ft. lbs.).

3. Position the seat back latch cable plunger (2)

against the retractor latch lever (1), then engage
the cable fitting (3) into the cable support (5) on the
retractor (4), which is a light snap fit.

4. Route the rear seat belt lower anchor and belt web

guide through the top of the seat back panel.

5. Reinstall the trim onto the right rear seat back.

(Refer to 23 - BODY/SEATS/SEAT BACK COVER -
REAR - INSTALLATION).

6. Install and tighten the two screws that secure the

belt web guide to the top of the right rear seat back
panel. Tighten the screws to 2 N·m (20 in. lbs.).

7. Reinstall the right rear seat back panel into the

vehicle. (Refer to 23 - BODY/SEATS/SEAT BACK -
REAR - INSTALLATION).

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RESTRAINTS - SERVICE INFORMATION

8. Position the rear center seat belt lower anchor (6)

onto the stud (5) on the rear floor panel.

9. Reach between the base of the right rear seat back

(3) and the forward edge of the rear cargo floor to
install and tighten the screw (1) that secures the
rear center seat belt lower anchor to the floor
panel. Tighten the screw to 43 N·m (32 ft. lbs.).

10. Restore the cargo area carpet to the base of the

seat back panel and unfold the right rear seat
back to its upright position.

11. Reinstall the right center seat belt buckle unit (2)

onto the floor panel. (Refer to 8 - ELECTRICAL/
RESTRAINTS/SEAT

BELT

BUCKLE

INSTALLATION).

REAR OUTBOARD

1. Position the rear outboard seat belt and retractor

(4) to the C-pillar (1) as a unit.

2. Engage the retractor tab into the engagement hole

in the lower C-pillar.

3. Install and tighten the screw (9) that secures the

retractor bracket to the lower C-pillar. Tighten the
screw to 43 N·m (32 ft. lbs.).

4. Route the seat belt lower anchor (6) and turning

loop through the access hole in the quarter trim
panel (2).

5. Reinstall the quarter trim panel onto the C-pillar.

(Refer to 23 - BODY/INTERIOR/QUARTER TRIM
PANEL - INSTALLATION).

6. Position the lower seat belt anchor to the bracket

on the outboard side of the rear seat cushion
frame. Be certain that the anti-rotation tab on the anchor is engaged in the slot in the seat bracket.

7. Install and tighten the screw (5) that secures the lower seat belt anchor to the bracket on the outboard side of

the rear seat cushion frame. Tighten the screw to 43 N·m (32 ft. lbs.).

8. Position the seat belt turning loop to the upper C-pillar.

9. Install and tighten the screw (7) that secures the seat belt turning loop to the upper C-pillar. Tighten the screw to

43 N·m (32 ft. lbs.).

10. Fold and snap the trim cover (3) back into place to conceal the screw that secures the rear outboard seat belt

turning loop to the upper C-pillar.

RESTRAINTS - SERVICE INFORMATION

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SEAT BELT SWITCH

DESCRIPTION

The seat belt switches for this model are actually Hall
Effect-type sensors. This sensor consists of a fixed-
position, Hall Effect Integrated Circuit (IC) chip and a
small permanent magnet that are integral to the driver
side and passenger side front seat belt buckle (1). The
front seat belt buckles are located on stamped steel
stanchions and secured with a screw (3) to the
inboard side of each front seat cushion frame between
the seat and the floor panel transmission tunnel.

The seat belt switches are connected to the vehicle electrical system through a two-lead pigtail wire (4) and con-
nector on the front seat belt buckle-half, which is connected to a wire harness connector and take out of the seat
wire harness beneath the rear edge of each front seat cushion frame. A radio noise suppression capacitor is con-
nected in parallel with the IC where the two pigtail wire leads connect to the IC pins.

The seat belt switches cannot be adjusted or repaired and, if ineffective or damaged, the entire front seat belt buck-
le-half unit must be replaced.

OPERATION

The seat belt switches are designed to provide a status signal to the seat belt switch sense inputs of the Electro-
Mechanical Instrument Cluster (EMIC) indicating whether the driver side and passenger side front seat belts are
fastened. The EMIC uses these inputs to control the seat belt indicator based upon the status of the driver side and
passenger side front seat belt switches.

A spring-loaded plastic slide with a small, enclosed permanent magnet is integral to the buckle latch mechanism.
When a seat belt tip-half is inserted and latched into the seat belt buckle, the slide is pushed downward and into
close proximity of the Hall Effect Integrated Circuit (IC) chip within the buckle. The field of the permanent magnet
induces a current within the chip. The chip provides this induced current as an output to the EMIC, which monitors
the current to determine the status of the front seat belts. When the seat belt is unbuckled, the spring-loaded slide
and permanent magnet move upward and away from the IC, causing the output current from the seat belt switch to
be reduced.

The seat belt switch receives a supply of current from the EMIC, and the EMIC senses the status of the front seat
belt through its pigtail wire connection to the seat wire harness. The EMIC also monitors the condition of the seat
belt switch circuit and will store a Diagnostic Trouble Code (DTC) for any fault that is detected in the seat belt switch
circuit. For proper diagnosis of the seat belt switch, a diagnostic scan tool is required. Refer to the appropriate
diagnostic information.

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RESTRAINTS - SERVICE INFORMATION

SEAT BELT TENSIONER

DESCRIPTION

Seat belt tensioners supplement the dual front airbag
system for all versions of this model. The seat belt
tensioners are integral to the front seat belt and
retractor units (1), which are secured to the B-pillars
on the right and left sides of the vehicle. The retrac-
tors are concealed beneath the molded plastic B-pillar
trim. The seat belt tensioner consists primarily of a
molded plastic tensioner housing (2), a tubular metal
piston housing (3), a piston, a short rack gear, a set of
pinion gears, a pyrotechnically activated gas generator
(5), and a short pigtail wire (4).

All of these components are located on one side of the retractor spool on the outside of the retractor housing. The
seat belt tensioners are controlled by the Airbag Control Module (ACM) and are connected to the vehicle electrical
system through dedicated take outs of the body wire harness by keyed and latching molded plastic connector insu-
lators to ensure a secure connection.

The seat belt tensioners cannot be repaired and, if faulty or damaged, the entire front seat belt and retractor unit
must be replaced. The seat belt 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. (Refer to 8 - ELECTRICAL/
RESTRAINTS/FRONT SEAT BELT & RETRACTOR - REMOVAL).

OPERATION

The seat belt tensioners are deployed by a signal generated by the Airbag Control Module (ACM) through the driver
or 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 initiate a small pyrotechnic gas generator.
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.

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 and/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 ACM monitors the condition of the seat belt tensioners through circuit resistance, and will illuminate the airbag
indicator in the ElectroMechanical Instrument Cluster (EMIC) and store a Diagnostic Trouble Code (DTC) for any
fault that is detected. For proper diagnosis of the seat belt tensioners, a diagnostic scan tool is required. Refer to
the appropriate diagnostic information.

RESTRAINTS - SERVICE INFORMATION

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