Part 2 of 3
FRONT WASHER HOSES/TUBESThe front washer plumbing consists of a small diameter rubber hose that is routed from the barbed outlet nipple of the front washer pump/motor on the washer reservoir through the engine compartment along the headlamp and dash wire harness near the right inner fender shield to the dash panel. The front washer hose passes from the engine compartment into the cowl plenum area through a dedicated hole with a rubber grommet near the right end of the cowl plenum panel. Beneath the cowl plenum cover/grille panel, a molded plastic in-line fitting with barbed nipples joins the engine compartment hose to a cowl plenum cover/grille panel hose. The cowl plenum cover/grille panel hose is routed through locating clips molded to the underside of the cowl plenum cover/grille panel to a molded plastic eye fitting with barbed nipples and an integral check valve near the passenger side washer nozzle. Two hoses are then routed from the eye fitting through additional locating clips on the underside of the cowl plenum cover/grille panel to the two washer nozzles.
Washer hose is available for service only as roll stock, which must then be cut to length. The molded plastic washer hose fittings cannot be repaired. If these fittings are faulty or damaged, they must be replaced.
Washer fluid in the washer reservoir is pressurized and fed by the front washer pump/motor through the front washer system plumbing and fittings to the two front washer nozzles. Whenever routing the washer hose or a wire harness containing a washer hose, it must be routed away from hot, sharp, or moving parts; and, sharp bends that might pinch the hose must be avoided.
FRONT WASHER NOZZLE
The two front washer nozzles have integral snap features that secure them in dedicated holes in the cowl plenum cover/grille panel located near the base of the windshield. The domed upper surface of the washer nozzle is visible on the top of the plenum cover/grille panel, and the nozzle orifice is oriented towards the windshield glass. The washer plumbing fittings for the front washer nozzles are concealed beneath the cowl plenum cover/grille panel. These fluidic washer nozzles are constructed of molded plastic. The cowl plenum cover/grille panel must be removed from the vehicle to access the nozzles for service. The front washer nozzles cannot be adjusted or repaired and, if faulty or damaged, they must be replaced.
The two front washer nozzles are designed to dispense washer fluid into the wiper pattern area on the outside of the windshield glass. Pressurized washer fluid is fed to each nozzle from the washer reservoir by the front washer pump/motor through rubber hoses, which are attached to a barbed nipple on each washer nozzle below the cowl plenum cover/grille panel. The front washer nozzles incorporate a fluidic design, which causes the nozzle to emit the pressurized washer fluid as an oscillating stream to more effectively cover a larger area of the glass area to be cleaned.
Fig. 2 Front Washer Pump/Motor:
WASHER PUMP/MOTOR
The front washer pump/motor unit is located on the outboard side of the washer reservoir, near the bottom in the right front corner of the engine compartment. A small permanently lubricated and sealed electric motor is coupled to the rotor-type washer pump. A seal flange with a large barbed inlet nipple on the pump housing passes through a rubber grommet seal installed in the dedicated mounting hole near the bottom of the washer reservoir. A smaller barbed outlet nipple on the pump housing connects the unit to the front washer hose. The front washer pump/motor unit is retained on the reservoir by the interference fit between the barbed pump inlet nipple and the grommet seal, which is a light press fit. An integral electrical connector receptacle is located on the motor housing. The front washer pump/motor unit cannot be repaired. If faulty or damaged, the entire washer pump/motor unit must be replaced.
The front washer pump/motor unit is connected to the vehicle electrical system through a single take out and two-cavity connector of the headlamp and dash wire harness. The front washer pump/motor is grounded at all times through a take out of the headlamp and dash wire harness with a single eyelet terminal connector that is secured by a nut to a ground stud located on the right front fender inner shield in the engine compartment. The front washer pump/motor receives battery current on a front washer pump/motor control circuit through an output of the Central Timer Module (CTM) whenever the CTM receives an input through the closed contacts of the momentary front washer switch within the multi- function switch. Washer fluid is gravity-fed from the washer reservoir to the inlet side of the washer pump. When the pump motor is energized, the rotor-type pump pressurizes the washer fluid and forces it through the pump outlet nipple, the front washer plumbing, and the front washer nozzles onto the windshield glass.
FRONT WIPER ARM
The front wiper arms are the rigid members located between the wiper pivots that protrude from the cowl plenum cover/grille panel near the base of the windshield and the wiper blades on the windshield glass. These wiper arms feature an over-center hinge that allows easy access to the windshield glass for cleaning. The wiper arm has a die cast metal pivot end with a large mounting hole with internal serrations at one end. A molded black plastic cap fits over the wiper arm retaining nut to conceal the nut and this mounting hole following wiper arm installation. The wide end of a tapered, stamped steel channel hinges on and is secured with a hinge pin to the blade end of the wiper arm pivot end. One end of a long, rigid, stamped steel strap, with a small hole near its pivot end, is riveted and crimped within the narrow end of the stamped steel channel. The tip of the wiper blade end of this strap is bent back under itself to form a small hook. Concealed within the stamped steel channel, one end of a long spring is engaged with a wire hook on the underside of the die cast pivot end, while the other end of the spring is hooked through the small hole in the steel strap. The entire wiper arm has a satin black finish applied to all of its visible surfaces.
A wiper arm cannot be adjusted or repaired. If damaged or faulty, the entire wiper arm unit must be replaced.
The front wiper arms are designed to mechanically transmit the motion from the wiper pivots to the wiper blades. The wiper arm must be properly indexed to the wiper pivot in order to maintain the proper wiper blade travel on the glass. The mounting hole formation with internal serrations in the wiper arm pivot end interlocks with the serrations on the outer circumference of the wiper pivot driver, allowing positive engagement and finite adjustment of this connection. The mounting nut locks the wiper arm to the threaded stud on the wiper pivot. The spring-loaded wiper arm hinge controls the down-force applied through the tip of the wiper arm to the wiper blade on the glass. The hook formation on the tip of the wiper arm provides a cradle for securing and latching the wiper blade pivot block to the wiper arm.
FRONT WIPER BLADE
Each wiper blade is secured by an integral latching pivot block to the hook formation on the tip of the wiper arms, and rests on the glass near the base of the windshield when the wipers are not in operation. The wiper blade consists of the following components:
- Superstructure - The superstructure includes several stamped steel bridges and links with claw formations that grip the wiper blade element. The driver side and passenger side wiper blades are not interchangeable. The superstructure of the driver side blade features an additional bridge, which provides an additional set of claws to retain the wiper squeegees. Their are eight sets of claws on the driver side, and six sets of claws used on the passenger side. Also included in this unit is the latching, molded plastic pivot block that secures the super-structure to the wiper arm. All of the metal components of the wiper blade have a satin black finish applied.
- Element - The wiper element or squeegee is the resilient rubber member of the wiper blade that contacts the glass.
- Flexor - The flexor is a rigid metal component running along the length of each side of the wiper element where it is gripped by the claws of the superstructure.
All Durango models have two 50 centimeter (19.69 inch) wiper blades with non-replaceable rubber elements (squeegees). These wiper blades also include an anti-lift feature. The wiper blades cannot be adjusted or repaired. If faulty, worn, or damaged the entire wiper blade unit must be replaced.
The wiper blades are moved back and forth across the glass by the wiper arms when the wipers are being operated. The wiper blade superstructure is the flexible frame that grips the wiper blade element and evenly distributes the force of the spring-loaded wiper arm along the length of the element. The combination of the wiper arm force and the flexibility of the superstructure makes the element conform to and maintain proper contact with the glass, even as the blade is moved over the varied curvature found across the glass surface. The wiper element flexor provides the claws of the blade superstructure with a rigid, yet flexible component on the element which can be gripped. The rubber element is designed to be stiff enough to maintain an even cleaning edge as it is drawn across the glass, but resilient enough to conform to the glass surface and flip from one cleaning edge to the other each time the wiper blade changes directions.
FRONT WIPER MODULE
The wiper module is secured with screws through four rubber grommet-type insulators to the cowl plenum panel and concealed within the cowl plenum area beneath the cowl plenum cover/grille panel. The ends of the wiper pivot shafts that protrude through dedicated openings in the cowl plenum cover/grille panel to drive the wiper arms and blades are the only visible components of the wiper module. The wiper module consists of the following major components:
- Bracket - The wiper module bracket consists of a long tubular steel main member that has a stamped pivot bracket formation near each end where the two wiper pivots are secured. A stamped steel mounting plate for the wiper motor is secured with welds near the center of the main member.
- Crank Arm - The wiper motor crank arm is a stamped steel unit that has a slotted hole on the driven end that is secured to the wiper motor output shaft with a nut, and has a ball stud secured to the drive end.
- Linkage - The two wiper linkage members are each constructed of stamped steel. A driver side drive link with a plastic socket-type bushing in the left end, and a plastic sleeve-type bushing in the right end. Socket bushing is snap-fit over the pivot ball stud on the left pivot, while the sleeve bushing is fit over the longer wiper motor crank arm pivot stud. The passenger side drive link has a plastic socket-type bushing on each end. One end of this drive link is snap-fit over the pivot ball stud on the right pivot, while the other end is snap-fit over the exposed end of the longer ball stud on the wiper motor crank arm.
- Motor - The wiper motor is secured with three screws to the motor mounting plate near the center of the wiper module bracket. The wiper motor output shaft passes through a hole in the module bracket, where a nut secures the wiper motor crank arm to the motor output shaft. The two-speed permanent magnet wiper motor features an integral transmission, an internal park switch, and an internal Positive Temperature Coefficient (PTC) circuit breaker.
- Pivots - The two wiper pivots are secured to the ends of the wiper module bracket. The crank arms that extend from the bottom of the pivot shafts each have a ball stud on their end. The upper end of each pivot shaft where the wiper arms will be fastened each has an externally serrated drum secured to it.
The wiper module cannot be adjusted or repaired. If any component of the module is faulty or damaged, the entire wiper module unit must be replaced.
The wiper module operation is controlled by the vehicle operator through battery current inputs received by the wiper motor from the multi-function switch on the steering column. The wiper motor speed is controlled by current flow to either the low speed or the high speed set of brushes. The park switch is a single pole, single throw, momentary switch within the wiper motor that is mechanically actuated by the wiper motor transmission components. The park switch alternately closes the wiper park switch sense circuit to ground or to battery current, depending upon the position of the wipers on the glass. This feature allows the motor to complete its current wipe cycle after the wiper system has been turned OFF, and to park the wiper blades in the lowest portion of the wipe pattern. The automatic resetting circuit breaker protects the motor from overloads. The wiper motor crank arm, the two wiper linkage members, and the two wiper pivots mechanically convert the rotary output of the wiper motor to the back and forth wiping motion of the wiper arms and blades on the glass.