Jeep Liberty KJ. Manual - part 308

WIPERS/WASHERS - SERVICE INFORMATION

DESCRIPTION

FRONT

An electrically operated intermittent front wiper and washer system is standard factory-installed safety equipment on
this vehicle. The wiper and washer system includes the following major components, which are described in further
detail elsewhere in this service information:

•

Body Control Module - The Body Control Module (BCM) is located on the Junction Block (JB) under the
driver side outboard end of the instrument panel. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MOD-
ULES/BODY CONTROL MODULE - DESCRIPTION).

•

Front Check Valve - The front washer system check valve is integral to the wye fitting located in the washer
plumbing between the cowl plenum washer hose and the front washer nozzles, and is concealed beneath the
cowl plenum cover/grille panel at the base of the windshield.

•

Front Washer Nozzle (4) - Two fluidic front washer nozzles are secured by integral latch features to dedicated
openings in the cowl plenum cover/grille panel located near the base of the windshield.

•

Front Washer Plumbing - The plumbing for the washer system consists of rubber hoses and molded plastic
fittings. The plumbing is routed along the right side of the engine compartment from the washer reservoir, and

8R - 24

WIPERS/WASHERS - SERVICE INFORMATION

through the dash panel into the cowl plenum beneath the cowl plenum cover/grille panel to the washer noz-
zles.

•

Front Wiper Arms & Blades (5) - The two front wiper arms are secured with nuts to the threaded ends of the
two wiper pivot shafts, which extend through the cowl plenum cover/grille panel located near the base of the
windshield. The two front wiper blades are secured to the two wiper arms with an integral latch, and are
parked on the glass near the bottom of the windshield when the wiper system is not in operation.

•

Front Wiper Module (3) - The wiper pivot shafts are the only visible components of the front wiper module.
The remainder of the module is concealed within the cowl plenum area beneath the cowl plenum cover/grille
panel. The wiper module includes the wiper module bracket, four rubber-isolated wiper module mounts, the
wiper motor, the wiper motor crank arm, the two wiper drive links, and the two wiper pivots.

•

Multi-Function Switch (6) - The multi-function switch is located on the top of the steering column, just below
the steering wheel. The multi-function switch includes a left (lighting) control stalk and a right (wiper) control
stalk. The right control stalk is dedicated to providing all of the driver controls for both the front and rear wiper
systems. (Refer to 8 - ELECTRICAL/LAMPS/LIGHTING - EXTERIOR/MULTI-FUNCTION SWITCH - DESCRIP-
TION).

•

Washer Fluid Level Switch - The washer fluid level switch is located in a dedicated hole near the center of
the rearward facing surface of the washer reservoir, behind the right front wheel house splash shield.

•

Washer Pump/Motor - The reversible electric washer pump/motor unit is located in a dedicated hole on the
lower outboard side of the washer reservoir, behind the right front wheel house splash shield. This single
reversible washer pump/motor provides washer fluid to either the front or rear washer system plumbing,
depending upon the direction of the pump motor rotation.

•

Washer Reservoir (1 & 2) - The washer reservoir (2) is concealed behind the right front wheel house splash
shield ahead of the right front wheel. The washer reservoir filler neck (1) is the only visible portion of the
reservoir, and it is accessed from the right front corner of the engine compartment.

•

Wiper High/Low Relay - The wiper high/low relay is an International Standards Organization (ISO) micro relay
located in the Power Distribution Center (PDC) in the engine compartment near the battery.

•

Wiper On/Off Relay - The wiper on/off relay is an International Standards Organization (ISO) micro relay
located in the Power Distribution Center (PDC) in the engine compartment near the battery.

Hard wired circuitry connects the front wiper and washer system components to the electrical system of the vehicle.
These hard wired circuits are integral to several wire harnesses, which are routed throughout the vehicle and
retained by many different methods. These circuits may be connected to each other, to the vehicle electrical system
and to the front wiper and washer system components through the use of a combination of soldered splices, splice
block connectors, and many different types of wire harness terminal connectors and insulators. Refer to the appro-
priate wiring information. The wiring information includes wiring diagrams, proper wire and connector repair proce-
dures, further details on wire harness routing and retention, as well as pin-out and location views for the various
wire harness connectors, splices and grounds.

WIPERS/WASHERS - SERVICE INFORMATION

8R - 25

REAR

An electrically operated fixed interval intermittent rear wiper and washer system is standard factory-installed equip-
ment on this vehicle. The rear wiper and washer system includes the following major components, which are
described in further detail elsewhere in this service information:

•

Multi-Function Switch - The multi-function switch is located on the top of the steering column, just below the
steering wheel. The multi-function switch includes a left (lighting) control stalk and a right (wiper) control stalk.
The right control stalk is dedicated to providing all of the driver controls for both the front and rear wiper sys-
tems. (Refer to 8 - ELECTRICAL/LAMPS/LIGHTING - EXTERIOR/MULTI-FUNCTION SWITCH - DESCRIP-
TION).

•

Rear Check Valve - The rear washer system check valve function is performed by the diaphragm integral to
the valve body of the washer pump/motor unit in this vehicle. (Refer to 8 - ELECTRICAL/FRONT WIPERS/
WASHERS/WASHER PUMP/MOTOR - DESCRIPTION).

•

Rear Washer Nozzle (2) - A fluidic rear washer nozzle is secured by a latch feature to a mounting hole in the
roof outer panel above the rear flip-up glass opening.

•

Rear Washer Plumbing - The plumbing for the rear washer system consists of rubber hoses and molded
plastic fittings. The plumbing is routed along the right side of the engine compartment from the washer reser-
voir, through the dash into the passenger compartment, up the right cowl side and A-pillar to the headliner, and
above the headliner to the rear washer nozzle on the rear roof header.

•

Rear Wiper Arm & Blade (3) - The single rear wiper arm is secured by a nut directly to the rear wiper motor
output shaft, which extends through the center of the tailgate outer panel near the base of the rear flip-up
glass. The single rear wiper blade is secured to the rear wiper arm with an integral latch, and is parked off of
the rear flip-up glass when the rear wiper system is not in operation.

•

Rear Wiper Arm Park Ramp (4) - The molded rubber rear wiper arm park ramp is secured with a screw to the
tailgate outer panel to the right of the rear wiper motor output shaft bezel. When the rear wiper system is not
in operation, the rear wiper arm is parked off of the rear flip-up glass on this ramp so that it will not interfere
with or be damaged by the flip-up glass operation.

•

Rear Wiper Module (1) - The rear wiper motor output shaft is the only visible component of the rear wiper
module. The remainder of the module is concealed within the tailgate below the rear flip-up glass opening. The
rear wiper module includes the module bracket, the rear wiper motor, and the rear wiper electronic control
circuitry.

•

8R - 26

WIPERS/WASHERS - SERVICE INFORMATION

reversible washer pump/motor provides washer fluid to either the front or rear washer system plumbing,
depending upon the direction of the pump motor rotation. (Refer to 8 - ELECTRICAL/FRONT WIPERS/WASH-
ERS/WASHER PUMP MOTOR - DESCRIPTION).

•

Washer Reservoir - The washer reservoir is concealed behind the right front wheel house splash shield ahead
of the right front wheel. The washer reservoir filler neck is the only visible portion of the reservoir, and it is
accessed from the right front corner of the engine compartment. This single washer reservoir is shared by both
the front and rear washer systems. (Refer to 8 - ELECTRICAL/FRONT WIPERS/WASHERS/WASHER RES-
ERVOIR - DESCRIPTION).

Hard wired circuitry connects the rear wiper and washer system components to the electrical system of the vehicle.
These hard wired circuits are integral to several wire harnesses, which are routed throughout the vehicle and
retained by many different methods. These circuits may be connected to each other, to the vehicle electrical system
and to the rear wiper and washer system components through the use of a combination of soldered splices, splice
block connectors, and many different types of wire harness terminal connectors and insulators. Refer to the appro-
priate wiring information. The wiring information includes wiring diagrams, proper wire and connector repair proce-
dures, further details on wire harness routing and retention, as well as pin-out and location views for the various
wire harness connectors, splices and grounds.

OPERATION

FRONT

The front wiper and washer system is designed to provide the vehicle operator with a convenient, safe, and reliable
means of maintaining visibility through the windshield glass. The various components of this system are designed to
convert electrical energy produced by the vehicle electrical system into the mechanical action of the wiper blades to
wipe the outside surface of the glass, as well as into the hydraulic action of the washer system to apply washer fluid
stored in an on-board reservoir to the area of the glass to be wiped. When combined, these components provide the
means to effectively maintain clear visibility for the vehicle operator by removing excess accumulations of rain,
snow, bugs, mud, or other minor debris from the outside windshield glass surface that might be encountered while
driving the vehicle under numerous types of inclement operating conditions.

The vehicle operator initiates all front wiper and washer system functions with the right (wiper) control stalk of the
multi-function switch that extends from the right side of the steering column, just below the steering wheel. Rotating
the control knob on the end of the control stalk, selects the Off, Delay, Low, or High front wiper system operating
modes. In the Delay mode, the control knob also allows the vehicle operator to select from one of five intermittent
wipe Delay intervals. Pulling the right control stalk downwards actuates the momentary front wiper system Mist
mode switch, while pulling the right control stalk towards the steering wheel actuates the momentary front washer
system switch. The multi-function switch provides hard wired resistor multiplexed inputs to the Body Control Module
(BCM) for all of the front wiper system functions, as well as a separate hard wired sense input to the BCM for the
front washer system function.

The front wiper and washer system will only operate when the ignition switch is in the Accessory or On positions.
Battery current is directed from a B(+) fuse in the Power Distribution Center (PDC) to the wiper and washer system
circuit breaker in the Junction Block (JB) through a fused ignition switch output (run-acc) circuit. The automatic
resetting circuit breaker then provides battery current through a fused ignition switch output (run-acc) circuit to the
wiper high/low relay, the wiper on/off relay, and the park switch within the front wiper motor. A separate fuse in the
JB provides battery current through another fused ignition switch output (run-acc) circuit to the multi-function switch.
The multi-function switch circuitry uses this battery feed and a ground circuit input to directly control the operation
and direction of the reversible electric washer pump/motor unit. The BCM uses low side drivers to control front wiper
system operation by energizing or de-energizing the wiper high/low and wiper on/off relays.

The hard wired circuits and components of the front wiper and washer system may be diagnosed and tested using
conventional diagnostic tools and procedures. However, conventional diagnostic methods may not prove conclusive
in the diagnosis of the Body Control Module (BCM), or the inputs to or outputs from the BCM that control the front
wiper and washer system operating modes. The most reliable, efficient, and accurate means to diagnose the BCM,
or the BCM inputs and outputs related to the various front wiper and washer system operating modes requires the
use of a diagnostic scan tool. Refer to the appropriate diagnostic information.

OPERATING MODES

Following are paragraphs that briefly describe the operation of each of the wiper and washer system operating
modes.

WIPERS/WASHERS - SERVICE INFORMATION

8R - 27

Content .. 306 307 308 309 ..