RAM 1500 Truck 4WD V8-5.9L VIN Z (2002)
Seat Belt Tensioner: Description and Operation
Seat Belt Tension Reducer
Fig. 47 Seat Belt Tensioner
SEAT BELT TENSION REDUCER
A seat belt tension reducer is standard equipment for the driver side front outboard seat belt on standard cab versions of this model. 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 insulator 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 RESTRAINTS/ FRONT OUTBOARD SEAT BELT & RETRACTOR - REMOVAL).
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 current
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 webbing 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
desirable 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.
