Part 1 of 3

REAR WASHER HOSES/TUBES
The rear washer plumbing consists of small diameter rubber hose, the molded plastic rear washer system check valve, and numerous routing clips. The rear washer system engine compartment hose is connected to the barbed outlet nipple of the rear washer pump/motor unit on the washer reservoir and routed through the engine compartment along the headlamp and dash wire harness near the right inner fender shield to the back of the right front wheel house. At the back of the right front wheel house, the engine compartment hose is joined to the passenger compartment hose by the molded plastic rear washer system check valve. The passenger compartment hose passes through a hole with a rubber grommet in the dash panel into the passenger compartment. The passenger compartment hose is then routed below the instrument panel, down the right cowl side inner panel, and along the right side of the floor panel near the body wire harness to the right rear wheel house. At the rear wheel house, the passenger compartment hose is routed up to the right quarter inner panel and below the quarter glass opening to the D-pillar at the rear of the vehicle. At the rear of the vehicle, the passenger compartment hose is routed up the D-pillar and along the upper liftgate opening inner panel toward the left side of the vehicle. Near the center of the liftgate opening the hose passes through a clearance hole in the liftgate opening inner panel and through a rubber grommet in a hole in the upper liftgate opening outer panel to the outside of the vehicle. From the outside of the vehicle, the hose passes through another hole with a rubber grommet into the upper inner liftgate panel to the rear washer nozzle.

Washer hose is available for service only as roll stock, which must then be cut to length. The molded plastic washer hose fittings and routing clips cannot be repaired. If these fittings or clips are faulty or damaged, they must be replaced.

Washer fluid in the washer reservoir is pressurized and fed by the rear washer pump/motor through the rear washer system plumbing and fittings to the rear washer nozzle on the liftgate outer panel above the liftgate glass. 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.

REAR WASHER NOZZLE
The rear washer nozzle is a fluidic type unit constructed of molded plastic and has a rubber seal and integral snap features on the back of it. The nozzle is secured by a snap fit in a dedicated mounting hole in the liftgate outer panel above the liftgate glass. The rear washer nozzle unit cannot be adjusted or repaired. If faulty or damaged, the entire nozzle unit must be replaced.

The rear washer nozzle is designed to dispense washer fluid into the wiper pattern area on the outside of the liftgate glass. Pressurized washer fluid is fed to the nozzle from the washer reservoir by the rear washer pump/motor through a single hose, which is attached to a barbed nipple on the back of the rear washer nozzle. The rear washer nozzle incorporates 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.5 Rear Washer Pump/Motor:

REAR WASHER PUMP/MOTOR
The rear 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 one of two dedicated mounting holes near the bottom of the washer reservoir. The rear washer pump/motor unit is always mounted in the upper pump mounting hole of the reservoir. A smaller barbed outlet nipple on the pump housing connects the unit to the rear washer hose. The rear 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 rear washer pump/motor unit cannot be repaired. If faulty or damaged, the entire washer pump/motor unit must be replaced.

The rear 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 rear 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 rear washer pump/motor receives battery current on a rear washer pump/motor control circuit through an output of the air conditioner-heater control whenever the momentary contacts of the rear washer switch within the air conditioner-heater control are closed. 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 rear washer plumbing, and the rear washer nozzle onto the liftgate glass.

Fig.7 Rear Wiper Arm:

REAR WIPER ARM
The rear wiper arm is the rigid member located between the rear wiper motor output shaft that protrudes from the outer liftgate panel near the base of the liftgate glass opening and the rear wiper blade. The wiper arm has a die cast metal pivot end. This pivot end has a mounting hole in it with internal serrations. 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 is secured with a hinge pin to the pivot end of the wiper arm. 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 to the hinge pin 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 rear wiper arm is designed to mechanically transmit the motion from the rear wiper motor output shaft to the rear wiper blade. The wiper arm must be properly indexed to the motor output shaft in order to maintain the proper wiper blade travel on the glass. The hole with internal serrations in the wiper arm pivot end interlocks with the serrations on the outer circumference of the motor output shaft, allowing positive engagement and finite adjustment of this connection. A hex nut secures the wiper arm pivot end to the threads on the motor output shaft and the plastic nut cap snaps over this connection for a neat appearance. 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.

Fig.10 Rear Wiper Blade:

REAR WIPER BLADE
The rear wiper blade is secured by an integral latching pivot block to the hook formation on the tip of the rear wiper arm, and rests on the glass near the base of the liftgate glass when the wiper is not in operation. The rear wiper blade consists of the following components:
- Superstructure - The superstructure includes a stamped steel bridge and plastic links with claw formations that grip the wiper blade element. Also included in this unit is the latching, molded plastic pivot block that secures the superstructure 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 with the rear wiper and washer system have one 40.0-centimeter (15.75-inch) rear wiper blade with a non-replaceable element (squeegee). The wiper blade cannot be adjusted or repaired. If faulty, worn, or damaged the entire wiper blade unit must be replaced.

The rear wiper blade is moved back and forth across the glass by the wiper arm when the rear wiper system is in operation. 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 liftgate 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.

Fig.12 Rear Wiper Motor:

REAR WIPER MOTOR
The rear wiper motor is concealed within the liftgate, below the liftgate glass and behind the liftgate trim panel. The end of the motor output shaft that protrudes through the liftgate outer panel to drive the rear wiper arm and blade is the only visible component of the rear wiper motor. A rubber bezel and grommet is secured with a nut to the motor output shaft to seal and secure the unit to the liftgate outer panel, and a plastic nut cover snaps over the top of the bezel for a neat appearance. The rear wiper motor consists of the following major components:
- Bracket - The rear wiper motor bracket consists of a stamped steel mounting plate for the wiper motor that is secured with screws to the wiper motor housing, and through two rubber grommet-type insulators to the liftgate inner panel.
- Motor - The single-speed permanent magnet rear wiper motor is secured with screws to the rear wiper module bracket. The wiper motor includes an integral transmission, a motor output shaft, an automatic re-setting circuit breaker, and the rear wiper motor park switch.

The rear wiper motor cannot be adjusted or repaired. If any component of the motor is faulty or damaged, the entire rear wiper motor unit must be replaced. The motor output shaft bezel and grommet, nut, and nut cap are available for service replacement.

The rear wiper motor operation is controlled by the rear wiper relay which controls battery current flow to the rear wiper motor brushes based upon control outputs from the Central Timer Module (CTM). The CTM uses internal programming, hard wired outputs from the rear wiper motor park switch, and electronic messages received over the Programmable Communications Interface (PCI) data bus network from the rear wiper and washer switches in the air conditioner-heater control to determine when to energize or de-energize the rear wiper relay. The rear wiper motor 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 and opens a path to ground for the rear wiper motor control circuit input to the CTM, depending upon the position of the rear wiper blade on the liftgate glass. This feature allows the CTM to monitor the number of rear wiper motor cycles, as well as to keep the rear wiper relay energized long enough for the motor to complete its current wipe cycle after the wiper system or the ignition has been turned OFF and to park the wiper blade in the lowest portion of the wipe pattern. The rear wiper motor is grounded at all times through a take out with an eyelet terminal connector in the body wire harness that is secured by a nut to a ground stud located on the lower left D-pillar in the passenger compartment. The automatic resetting circuit breaker protects the motor from overloads. The rear wiper motor transmission converts the rotary output of the wiper motor to the back and forth wiping motion of the rear wiper arm and blade on the liftgate glass.

REAR WIPER RELAY
The rear wiper relay is located in the Power Distribution Center (PDC) near the battery in the engine compartment. See the fuse and relay layout label affixed to the inside surface of the PDC cover for rear wiper relay identification and location. The rear wiper relay is a conventional International Standards Organization (ISO) micro relay Relays conforming to the ISO specifications have common physical dimensions, current capacities, terminal patterns, and terminal functions. The relay is contained within a small, rectangular, molded plastic housing. The relay is connected to all of the required inputs and outputs through its PDC receptacle by five male spade-type terminals that extend from the bottom of the relay base. The ISO designation for each terminal is molded into the base adjacent to the terminal. The ISO terminal designations are as follows:
- 30 (Common Feed) - This terminal is connected to the movable contact point of the relay
- 85 (Coil Ground) - This terminal is connected to the ground feed side of the relay control coil.
- 86 (Coil Battery) - This terminal is connected to the battery feed side of the relay control coil.
- 87 (Normally Open) - This terminal is connected to the normally open fixed contact point of the relay.
- 87A (Normally Closed) - This terminal is connected to the normally closed fixed contact point of the relay.

The rear wiper relay cannot be adjusted or repaired. If the relay is damaged or faulty, it must be replaced.

The rear wiper relay is an electromechanical switch that uses a low current input from the Central Timer Module (CTM) to control a high current output to the rear wiper motor. The movable common feed contact point is held against the fixed normally closed contact point by spring pressure. When the relay coil is energized, an electromagnetic field is produced by the coil windings. This electromagnetic field draws the movable relay contact point away from the fixed normally closed contact point, and holds it against the fixed normally open contact point. When the relay coil is de-energized, spring pressure returns the movable contact point back against the fixed normally closed contact point. A resistor or diode is connected in parallel with the relay coil in the relay, and helps to dissipate voltage spikes and electromagnetic interference that can be generated as the electromagnetic field of the relay coil collapses.

The rear wiper relay terminals are connected to the vehicle electrical system through a connector receptacle in the Power Distribution Center (PDC). The inputs and outputs of the rear wiper relay include:
- The common feed terminal (30) is connected to the rear wiper motor through the rear wiper motor control circuit to the rear wiper motor. When the rear wiper relay is de-energized, the common feed terminal is connected to ground through a take out and eyelet terminal connector of the headlamp and dash wire harness that is secured by a nut to a ground stud located on the left front fender inner shield in the engine compartment near the battery. When the rear wiper relay is energized, the common feed terminal of the relay is connected to battery current from a fuse in the Power Distribution Center (PDC) through a fused B(+) circuit.
- The coil ground terminal (85) is connected to the relay control output of the CTM through the rear wiper relay control circuit. The CTM controls the ground path for this circuit internally to energize or de-energize the rear wiper relay based upon its programming, electronic wiper and washer switch state message inputs from the heater-air conditioner control, and a hard wired input from the rear wiper motor park switch.
- The coil battery terminal (86) is connected to battery current from a fuse in the PDC through a fused B(+) circuit at all times.
- The normally open terminal (87) is connected to battery current from a fuse in the PDC through a fused B(+) circuit at all times.
- The normally closed terminal (87A) is connected to ground through a take out and eyelet terminal connector of the headlamp and dash wire harness that is secured by a nut to a ground stud located on the left front fender inner shield in the engine compartment near the battery.

The rear wiper relay can be diagnosed using conventional diagnostic tools and methods.