windshield washer motor fuse JEEP LIBERTY 2002 KJ / 1.G Workshop Manual

²Intermittent Wipe Mode- The control knob on
the right (wiper) control stalk of the multi-function
switch has five minor detent intermittent wipe posi-
tions. When selected, these switch positions will
cause the front wiper system to operate with one of
five delay intervals between complete wipe cycles.
²Mist Wipe Mode- The right (wiper) control
stalk of the multi-function switch has a momentary
Mist position. When selected, this switch position
will operate the front wipers in a low speed continu-
ous cycle for as long as the switch is held closed,
then will complete the current wipe cycle and park
the front wiper blades near the base of the wind-
shield when the switch is released.
²Washer Mode- When the momentary front
wash position of the right (wiper) control stalk of the
multi-function switch is selected with the front wiper
system operating in a continuous wipe mode, washer
fluid will be dispensed onto the windshield glass
through the washer nozzles for as long as the washer
switch is held closed. When the front washer switch
is actuated with the front wiper system operating in
an intermittent wipe mode, washer fluid is still dis-
pensed until the switch is released; however, the
front wipers will operate in a low speed continuous
cycle from the time the washer switch is closed until
several wipe cycles after the switch is released,
before returning to the selected intermittent wipe
mode.
²Wipe-After-Wash Mode- When the momentary
front wash position of the right (wiper) control stalk
of the multi-function switch is selected with the front
wiper system turned Off, the internal circuitry of the
BCM provides a wipe-after-wash feature. When
selected, this feature will operate the washer pump/
motor and the front wipers for as long as the front
washer switch is held closed, then provide several
additional wipe cycles after the switch is released
before parking the front wiper blades near the base
of the windshield.
OPERATION
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 pro-
duced 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 main-
tain clear visibility for the vehicle operator by remov-
ing excess accumulations of rain, snow, bugs, mud, orother 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) con-
trol 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 down-
wards 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 multi-
plexed 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 oper-
ate 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 Junc-
tion Block (JB) through a fused ignition switch out-
put (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/mo-
tor unit. The BCM uses low side drivers to control
front wiper system operation by energizing or de-en-
ergizing 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 meth-
ods may not prove conclusive in the diagnosis of the
Body Control Module (BCM), or the inputs to or out-
puts 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 DRBIIItscan tool. Refer to the
appropriate diagnostic information.
8R - 4 FRONT WIPERS/WASHERSKJ
FRONT WIPERS/WASHERS (Continued)

Following are paragraphs that briefly describe the
operation of each of the front wiper and washer sys-
tem operating modes.
CONTINUOUS WIPE MODE When the Low posi-
tion of the control knob on the right (wiper) control
stalk of the multi-function switch is selected, the
Body Control Module (BCM) energizes the wiper
on/off relay. This directs battery current through the
normally open contacts of the energized wiper on/off
relay and the normally closed contacts of the de-en-
ergized wiper high/low relay to the low speed brush
of the front wiper motor, causing the front wipers to
cycle at low speed. When the High position of the
control knob is selected, the BCM energizes both the
wiper on/off relay and the wiper high/low relay. This
directs battery current through the normally open
contacts of the energized wiper on/off relay and the
normally open contacts of the energized wiper high/
low relay to the high speed brush of the front wiper
motor, causing the front wipers to cycle at high
speed.
When the Off position of the control knob is
selected, the BCM de-energizes both the wiper on/off
and wiper high low relays, then one of two events
will occur. The event that occurs depends upon the
position of the wiper blades on the windshield at the
moment that the control knob Off position is selected.
If the wiper blades are in the down position on the
windshield when the Off position is selected, the
park switch that is integral to the front wiper motor
is closed to ground and the wiper motor ceases to
operate. If the wiper blades are not in the down posi-
tion on the windshield at the moment the Off posi-
tion is selected, the park switch is closed to battery
current from the fused ignition switch output (run-
acc) circuit of the front wiper motor. The park switch
directs this battery current to the low speed brush of
the wiper motor through the wiper park switch sense
circuit and the normally closed contacts of the de-en-
ergized wiper on/off and wiper high/low relays. This
causes the wiper motor to continue running at low
speed until the wiper blades are in the down position
on the windshield and the park switch is again
closed to ground.
INTERMITTENT WIPE MODE When the control
knob on the right (wiper) control stalk of the multi-
function switch is moved to one of the Delay interval
positions, the BCM electronic intermittent wipe logic
circuit responds by calculating the correct length of
time between wiper sweeps based upon the selected
delay interval input. The BCM monitors the chang-
ing state of the wiper motor park switch through a
hard wired front wiper park switch sense circuit
input. This input allows the BCM to determine the
proper intervals at which to energize and de-energize
the wiper on/off relay to operate the front wipermotor intermittently for one low speed cycle at a
time. The BCM logic is also programmed to provide
an immediate wipe cycle and begin a new delay
interval timing cycle each time a shorter delay inter-
val is selected, and to add the remaining delay tim-
ing interval to the new delay interval timing before
the next wipe cycle occurs each time a longer delay
interval is selected.
MIST WIPE MODE When the right (wiper) control
stalk of the multi-function switch is moved to the
momentary Mist position, the BCM energizes the
wiper on/off relay for as long as the Mist switch is
held closed, then de-energizes the relay when the
state of the Mist switch input changes to open. The
BCM can operate the front wiper motor in this mode
for only one low speed cycle at a time, or for an
indefinite number of sequential low speed cycles,
depending upon how long the Mist switch is held
closed.
WASH MODE When the right (wiper) control stalk
of the multi-function switch is moved to the momen-
tary front Wash position while the control knob is in
the Low or High positions, the circuitry within the
switch directs battery current and ground to the
washer pump/motor unit. This will cause the washer
pump/motor unit to be energized for as long as the
front Wash switch is held closed, and to de-energize
when the front Wash switch is released. When the
right (wiper) control stalk of the multi-function
switch is moved to the momentary front Wash posi-
tion while the control knob is in one of the Delay
interval positions, the front washer pump/motor oper-
ation is the same. However, the BCM energizes the
wiper on/off relay to override the selected delay inter-
val and operate the front wiper motor in a continu-
ous low speed mode for as long as the front Wash
switch is held closed, then de-energizes the relay and
reverts to the selected delay mode interval several
wipe cycles after the front Wash switch is released.
The BCM detects the front Wash switch state
through a hard wired washer pump driver circuit
input from the multi-function switch.
WIPE-AFTER-WASH MODE When the right
(wiper) control stalk of the multi-function switch is
moved to the momentary front Wash position while
the control knob is in the Off position, the BCM
detects that switch state through a hard wired
washer pump driver circuit input from the multi-
function switch. The BCM responds to this input by
energizing the wiper on/off relay for as long as the
Wash switch is held closed, then de-energizes the
relay several wipe cycles after the front Wash switch
is released. The BCM monitors the changing state of
the wiper motor park switch through a hard wired
front wiper park switch sense circuit input. This
input allows the BCM to count the number of wipe
KJFRONT WIPERS/WASHERS 8R - 5
FRONT WIPERS/WASHERS (Continued)