Dodge Nitro. Manual — part 251

Fig. 79: Identifying Second Row Center Seat Belt Retractor, Seat Back Panel, Bezel, Screw & Anchor
Unit
Courtesy of CHRYSLER LLC

1. Position the second row center seat belt and retractor unit (1) onto the 60 percent seat back panel (2). Be

certain to engage the tab on the retractor frame into the keyed hole in the back panel.

2. Install and tighten the screw (4) that secures the retractor to the seat back panel. Tighten the screw to 55

N.m (41 ft. lbs.).

3. Reinstall the foam, trim cover and bezel (3) onto the seat back panel. Be certain the seat belt webbing

between the retractor and the bezel is not twisted. Refer to ASSEMBLY .

4. Reinstall the second row seat into the vehicle as a unit. Refer to INSTALLATION .

5. Reinstall the left second row seat belt buckle and center seat belt lower anchor unit (5) onto the rear floor

panel. See INSTALLATION.

SEAT BELT SWITCH

DESCRIPTION

SEAT BELT SWITCH

NOTE:

The anchor plates for the left outboard second row seat belt buckle and the
second row center seat belt anchor are secured to each other by a soft metal
grommet as an assembly aid during the manufacturing process and, once
removed, the grommet does not require reinstallation.

2007 Dodge Nitro R/T

2007 RESTRAINTS Service Information - Nitro

Fig. 80: Identifying Front Seat Belt Buckle And Tensioner Unit, Screw & Pigtail Wire
Courtesy of CHRYSLER LLC

Two different seat belt switches are used in the front seat buckles of this vehicle. The driver side uses a
mechanical switch, while the passenger side is actually a Hall Effect-type sensor. The driver side switch is a
small, normally open, single pole, single throw, leaf contact, momentary switch. The driver side seat belt switch
is integral to the buckle of the driver side front seat belt buckle. The passenger side switch consists of a fixed-
position, Hall Effect Integrated Circuit (IC) chip and a small permanent magnet that is integral to the passenger
side front seat belt buckle. The front seat belt buckles (1) are located on a molded plastic scabbard and secured
along with the seat belt buckle tensioner mechanism by a screw (2) near the back of the inboard front seat
cushion frame.

The seat belt switches are connected to the vehicle electrical system through a two-lead pigtail wire (3) and a
four-way connector shared with the buckle tensioner squib circuits on the front seat belt buckle-half, which is
connected to a wire harness connector and take out of the seat wire harness routed beneath the front seat
cushion. On the passenger side, a one kilohm diagnostic resistor is connected 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. If ineffective or damaged, the entire front seat belt buckle-
half and tensioner unit must be replaced.

OPERATION

SEAT BELT SWITCH

DRIVER SIDE

The driver side front seat belt switch is a hard wired input to the Totally Integrated Power Module (TIPM),
which provides electronic driver side seat belt switch status messages to the Electro Mechanical Instrument
Cluster (EMIC) (also known as the Cab Compartment Node/CCN) over the Controller Area Network (CAN)
data bus. The EMIC controls the seat belt indicator based upon the electronic driver side seat belt switch status
message inputs.

2007 Dodge Nitro R/T

2007 RESTRAINTS Service Information - Nitro

When the driver side front seat belt tip-half is inserted into the seat belt buckle, the switch closes the path to
ground; and, when the driver side front seat belt tip-half is removed from the seat belt buckle, the switch opens
the ground path. The switch is actuated by the latch mechanism within the seat belt buckle.

The seat belt switch is connected in series between ground and the seat belt switch sense input of the TIPM. The
seat belt switch receives ground at all times through its pigtail wire connection to the seat wire harness from a
take out of the body wire harness. An eyelet terminal connector on the body wire harness ground take out is
secured beneath a ground screw on the left cowl side inner panel, beneath the instrument panel. The TIPM
monitors the condition of the driver seat belt switch circuits and will send an electronic message to illuminate
the airbag indicator in the EMIC then store a Diagnostic Trouble Code (DTC) for any fault that is detected.

The hard wired circuits between the driver side seat belt switch and the TIPM may be diagnosed using
conventional diagnostic tools and procedures. Refer to the appropriate wiring information. However,
conventional diagnostic methods will not prove conclusive in the diagnosis of the switch or the electronic
controls or communication between other modules and devices that provide features of the supplemental
restraint system. The most reliable, efficient, and accurate means to diagnose the driver side seat belt switch or
the electronic controls and communication related to seat belt switch operation requires the use of a diagnostic
scan tool. Refer to the appropriate diagnostic information.

PASSENGER SIDE

The passenger side front seat belt switch is a hard wired input to the Occupant Restraint Controller (ORC). A
spring-loaded slide with a small window-like opening 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 the window of
the slide exposes 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 ORC. When
the seat belt is unbuckled, the spring-loaded slide moves upward and shields the IC from the field of the
permanent magnet, causing the output current from the seat belt switch to be reduced.

The passenger side seat belt switch receives a clean ground from the ORC through a hard wired connection, and
the ORC senses the status of the seat belt buckle by monitoring the modulation of voltage through its
connection to the seat belt switch output. The ORC also monitors the condition of the passenger side seat belt
switch circuits and will send an electronic message to illuminate the airbag indicator in the EMIC then store a
DTC for any fault that is detected. However, the ORC is not currently programmed to provide any features in
response to the status of the passenger side seat belt switch input.

The hard wired circuits between the passenger side seat belt switch and the ORC may be diagnosed using
conventional diagnostic tools and procedures. Refer to the appropriate wiring information. However,
conventional diagnostic methods will not prove conclusive in the diagnosis of the switch or the electronic
controls or communication between other modules and devices that provide features of the supplemental
restraint system. The most reliable, efficient, and accurate means to diagnose the passenger side seat belt switch
or the electronic controls and communication related to seat belt switch operation requires the use of a
diagnostic scan tool. Refer to the appropriate diagnostic information.

SEAT BELT TENSIONER

DESCRIPTION

2007 Dodge Nitro R/T

2007 RESTRAINTS Service Information - Nitro

SEAT BELT TENSIONER

Both front seat belts incorporate dual tensioners: one integral to the retractor, and one integral to the buckle.

RETRACTOR TENSIONER

Fig. 81: Identifying Retractor Units, Molded Plastic Tensioner Housing, Tubular Metal Piston Housing,
Pigtail Wire & Gas Generator
Courtesy of CHRYSLER LLC

Seat belt retractor tensioners supplement the dual front and side curtain airbag system for all versions of this
vehicle. These 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 retractors 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 Occupant Restraint Controller (ORC) and are connected to the
vehicle electrical system through dedicated take outs of the body wire harness by keyed and latching molded
plastic connector insulators to ensure a secure connection.

The retractor tensioners cannot be repaired and, if ineffective or damaged, the entire front seat belt and retractor

2007 Dodge Nitro R/T

2007 RESTRAINTS Service Information - Nitro