Jeep Cherokee (XJ): Description and operation

Wiper arm and blade

All Cherokee models have two 45.72-centimeter (18-inch) windshield wiper blades with non-replaceable rubber elements (squeegees). The optional rear wiper uses a single 33.0-centimeter (13-inch) wiper blade with a non-replaceable rubber element (squeegee).

Caution should be exercised to protect the rubber squeegees from any petroleum-based cleaners or contaminants, which will rapidly deteriorate the rubber.

If the squeegees are damaged, worn, or contaminated, the entire wiper blade assembly must be replaced.

Wiper squeegees exposed to the elements for a long time tend to lose their wiping effectiveness. Periodic cleaning of the squeegees is suggested to remove deposits of salt and road film. The wiper blades, arms, and windshield or rear glass should be cleaned with a sponge or cloth and windshield washer fluid, a mild detergent, or a non-abrasive cleaner. If the squeegees continue to streak or smear, the wiper blades should be replaced.

The blades are mounted to spring-loaded wiper arms. The spring tension of the wiper arms controls the pressure applied to the blades on the glass. The windshield wiper arms are secured by an integral latch to the two wiper pivots on the cowl plenum cover/ grille panel at the base of the windshield. The rear wiper arm is secured by a nut directly to the rear wiper motor output shaft on the liftgate below the liftgate glass.

The wiper arms and blades cannot be adjusted or repaired. If faulty or damaged, they must be replaced.

Wiper linkage and pivot

The wiper linkage and pivot module is secured with screws to the cowl top panel beneath the cowl plenum cover/grille panel. The wiper motor is secured with screws to the center of the linkage and pivot module bracket. The wiper pivots are secured to the ends of the module bracket.

The two wiper pivot crank arms and the wiper motor crank arm each have ball studs on their ends.

The left pivot ball stud is the longer of the three. A connecting link with a plastic socket-type bushing in the right end, and a plastic sleeve-type bushing in the left end, is fit over the pivot ball studs to join the two pivots.

The wiper drive link has a plastic socket-type bushing on each end. One end of the drive link is snap-fit over the exposed end of the longer left pivot ball stud, while the other end is snap-fit over the ball stud on the wiper motor crank arm.

The wiper linkage, pivots, bushings, motor, crank arm, and mounting bracket are only serviced as a complete unit. If any part of this assembly is faulty or damaged, the entire unit must be replaced.

Wiper motor

FRONT

The two-speed permanent magnet wiper motor has an integral transmission and park switch. The motor also contains an internal automatic resetting circuit breaker to protect the motor from overloads.

The motor is secured to the wiper linkage and pivot module bracket with three screws and is protected by a rubber boot. 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. A reinforcement and stud plate with a rubber-isolated mounting bracket extends from the cowl plenum side of the dash panel to the motor mounting bracket to provide additional support.

Wiper speed is controlled by current flow to the proper set of brushes. The wiper motor completes its wipe cycle when the windshield wiper switch stalk is moved to the Off position, and parks the blades in the lowest portion of the wipe pattern.

The windshield wiper motor cannot be repaired. If faulty or damaged, the entire wiper linkage and pivot module unit must be replaced. The reinforcement bracket and stud plate are available for service.

REAR

The rear wiper motor is secured to a bracket that is fastened to the liftgate inner panel, below the liftgate glass and behind the liftgate trim panel. The motor output shaft passes through the liftgate outer panel where a rubber gasket and plastic bezel unit, and a nut seal and secure the unit to the liftgate outer panel. The rear wiper arm is secured directly to the motor output shaft with a nut.

The rear wiper motor unit provides three operating modes:

•  Constant wipe that operates when the rear wiper switch is turned to the On position.
•  Constant wipe that operates when the rear washer switch is depressed.
•  A park mode that operates the wiper motor until the blade reaches its park position when either the rear wiper switch or the ignition switch is placed in the Off position.

The rear wiper motor cannot be repaired. If faulty or damaged, the entire rear wiper motor assembly must be replaced.

Wiper switch and washer switch

FRONT

The windshield wiper and washer switches are mounted on the right side of the steering column (Fig. 1). The switch stalk is moved up or down to select the wiper switch mode, and pulled towards the steering wheel to activate the washer system. An intermittent wipe system control knob on the end of the switch stalk is rotated to select the desired delay interval. The windshield wiper and washer switch contains circuitry for the following functions:

•  Windshield wipers
•  Intermittent wiper delay relay control and logic
•  Intermittent wipe relay
•  Windshield washers.

The windshield wiper and washer switch cannot be repaired. If any function of the switch is faulty, or if the switch is damaged, the entire switch unit must be replaced.

REAR The single two-function rear wiper and washer switch is installed in the instrument panel accessory switch bezel, which is located near the bottom of the instrument panel center bezel area, below the heater and air conditioner controls. The rear wiper and washer switch controls the rear wiper and washer functions.

Fig. 1 Windshield Wiper Switch and Washer Switch

The toggle-type switch features a detent in the On position, and a momentary Wash position. The rear wiper and washer switch also has an integral illumination lamp with a serviceable bulb. The switch knob is pushed down to its detent to activate the rear wiper system, and down again to the momentary position to activate the rear washer system. Both the rear wiper and rear washer motors will operate continuously for as long as the switch is held in the momentary Wash position.

The rear wiper and washer switch cannot be repaired and, if faulty or damaged, the entire switch unit must be replaced.

Washer reservoir

A single washer fluid reservoir is used for both the standard front and optional rear washer systems.

The washer fluid reservoir is secured between the left front inner and outer fender panels, above and in front of the left front wheel house.

Each washer pump and motor unit has a barbed nipple, which is installed through a rubber grommet seal inserted in a hole near the bottom of the reservoir.

The washer pumps are retained by an interference fit between the barbed nipple and the grommet seal, which is a light press fit.

The washer reservoir has a separate filler neck and grommet seal. The filler neck snaps into the reservoir from the engine compartment side of the left inner fender shield. A snap-fit filler cap with an integral bail strap is fit to the reservoir filler neck. On models so equipped, the reservoir also has a hole provided for a washer fluid level sensor.

The washer reservoir, filler neck, grommet seal, and filler cap are each available for service.

Washer pump

The washer pumps and motors are mounted near the bottom of the washer reservoir. A barbed nipple on the pump housing passes through a rubber grommet seal installed in a hole near the bottom of the reservoir. The washer pump is retained by an interference fit between the barbed pump nipple and the grommet seal, which is a light press fit.

A permanently lubricated and sealed motor is coupled to a rotor-type pump. Washer fluid is gravity-fed from the reservoir to the pump. When the motor is energized, the pump pressurizes the washer fluid and forces it through the plumbing to the nozzles.

On vehicles with the optional rear wiper/washer system, the front washer pump and motor is always mounted in the lower hole of the reservoir. The washer pump and motor unit cannot be repaired. If faulty, the entire washer pump and motor unit must be replaced.

Washer fluid level sensor

The washer fluid level sensor is mounted near the front of the washer reservoir, above the two washer pumps. A barbed nipple on the sensor is press-fit into a rubber grommet seal installed in a hole in the front of the reservoir.

When the fluid level in the reservoir falls below the pivoting float on the sensor, the float changes position and closes the internal switch contacts of the sensor. Refer to Group 8E - Instrument Panel Systems for diagnosis of the low washer fluid warning lamp and circuit, including the sensor.

The washer fluid level sensor cannot be repaired. If faulty or damaged, the sensor unit must be replaced.

Washer nozzle and plumbing

FRONT

Pressurized washer fluid is fed through a single hose, attached to a barbed nipple on the front washer pump. The hose is routed to a tee fitting located in the cowl plenum area, beneath the cowl plenum cover/ grille panel. Hoses from the tee fitting are routed to the two nozzles, which are riveted into openings in the cowl plenum cover/grille panel below the windshield.

The two fluidic washer nozzles are not adjustable.

The nozzles and hose fittings cannot be repaired and, if faulty or damaged, they must be replaced.

REAR

Pressurized washer fluid is fed through a single hose, attached to a barbed nipple on the rear washer pump. The hose is routed from the front of the vehicle to the liftgate with the body wire harness.

Located at the highest point of the supply hose routing, beneath the liftgate opening upper header garnish moulding, the hose connects to a check valve.

The check valve prevents washer fluid drain-back or siphoning from occurring. From the check valve, another single hose is routed through a grommet to the liftgate, where it is connected to a nipple that protrudes from the inside of the rear wiper motor output shaft bezel.

The washer fluid passes through the bezel nipple to the outside of the liftgate. There a single hose is connected to a nipple on the outside of the rear wiper motor output shaft bezel. The hose is routed through a plastic trough-like guard snapped to the underside of the rear wiper arm. The hose is then attached to the single rear washer nozzle. The nozzle snaps into place on the rear wiper arm.

The rear washer nozzle cannot be adjusted. The nozzle, bezel, check valve, and hose fittings cannot be repaired and, if faulty or damaged, they must be replaced.