Durango 2WD V8-4.7L VIN N (2001)
Seat Belt Buckle Switch: Description and Operation
LUMBAR CONTROL SWITCH
The 8-way power seat option includes an electrically operated lumbar support mechanism. A single two-way momentary power lumbar switch is
integral with the power seat switches. The power lumbar switch is secured to the back of the seat cushion side shield with screws, and the switch
paddle protrudes through a hole to the outside of the shield. The switch paddle is located in a shallow depression molded into the outer surface of
the seat cushion side shield that helps to shroud it from unintentional actuation when entering or leaving the vehicle.
The power lumbar switches cannot be adjusted or repaired and, if faulty or damaged, the seat switch assembly must be replaced.
When the power lumbar switch paddle is actuated, a battery feed and a ground path are applied through the switch contacts to the power lumbar
adjuster motor. The motor operates to move the lumbar adjuster through its drive unit in the selected direction until the switch is released, or until
the travel limit of the adjuster is reached. When the switch is moved in the opposite direction, the battery feed and ground path to the motor are
reversed through the switch contacts. This causes the motor to run in the opposite direction.
The power lumbar switch should not be held applied in either direction after the adjuster has reached its travel limit. The power lumbar adjuster
motor contains a self-resetting circuit breaker to protect it from overload. However, consecutive or frequent resetting of the circuit breaker must
not be allowed to continue, or the motor may be damaged.
SEAT BELT SWITCH
The seat belt switch is a small, normally open, single pole, single throw, plunger actuated, momentary switch. Only one seat belt switch is installed
in the vehicle, and it is integral to the driver seat belt retractor assembly. The seat belt switch is connected to the vehicle electrical system through
a short pigtail wire to a dedicated take out and connector of the body wire harness.
The seat belt switch cannot be adjusted or repaired and, if faulty or damaged, the entire driver seat belt and retractor unit must be replaced.
The seat belt switch is designed to control a path to ground for the seat belt switch sense input of the Electro-Mechanical Instrument Cluster
(EMIC). The seat belt switch plunger is actuated by the seat belt webbing wound onto the seat belt retractor spool. When the seat belt tip-half
webbing is pulled out of the retractor far enough to engage the seat belt buckle-half, the switch plunger is extended and closes the seat belt switch
sense circuit to ground; and, when the seat belt tip-half webbing is wound onto the retractor the switch plunger is depressed, opening the ground
path. The EMIC monitors the seat belt switch status, then controls the seatbelt indicator and sends electronic chime request messages over the
Programmable Communications Interface (PCI) data bus to the Central Timer Module (CTM) based upon that input.
The seat belt switch receives ground through its pigtail wire connection to the body wire harness from another take out of the body wire harness.
An eyelet terminal connector on that ground take out is secured under a ground screw to the left lower B-pillar. The seat belt switch is connected
in series between ground and the seat belt switch sense input of the EMIC.
