wiper motor DODGE RAM 1500 1998 2.G Workshop Manual

RADIO NOISE SUPPRESSION
GROUND STRAP
DESCRIPTION
Radio noise suppression devices are factory-in-
stalled standard equipment on this vehicle. Radio
Frequency Interference (RFI) and ElectroMagnetic
Interference (EMI) can be produced by any on-board
or external source of electromagnetic energy. These
electromagnetic energy sources can radiate electro-
magnetic signals through the air, or conduct them
through the vehicle electrical system.
When the audio system converts RFI or EMI to an
audible acoustic wave form, it is referred to as radio
noise. This undesirable radio noise is generally man-
ifested in the form of ªbuzzing,º ªhissing,º ªpopping,º
ªclicking,º ªcrackling,º and/or ªwhirringº sounds. In
most cases, RFI and EMI radio noise can be sup-
pressed using a combination of vehicle and compo-
nent grounding, filtering and shielding techniques.
This vehicle is equipped with factory-installed radio
noise suppression devices that were designed to min-
imize exposure to typical sources of RFI and EMI;
thereby, minimizing radio noise complaints.
Factory-installed radio noise suppression is accom-
plished primarily through circuitry or devices that
are integral to the factory-installed radios, audio
power amplifiers and other on-board electrical com-
ponents such as generators, wiper motors, blower
motors, and fuel pumps that have been found to be
potential sources of RFI or EMI. External radio noise
suppression devices that are used on this vehicle to
control RFI or EMI, and can be serviced, include the
following:
²Engine-to-body ground strap- This length of
braided ground strap has an eyelet terminal connec-
tor crimped to each end. One end is secured to the
engine cylinder head(s). The other is secured to the
plenum at the exhaust heat shield forward/outer
attaching stud.
²Resistor-type spark plugs- This type of spark
plug has an internal resistor connected in series
between the spark plug terminal and the center elec-
trode to help reduce the production of electromag-
netic radiation that can result in radio noise.
OPERATION
There are two common strategies that can be used
to suppress Radio Frequency Interference (RFI) and
ElectroMagnetic Interference (EMI) radio noise. The
first suppression strategy involves preventing the
production of RFI and EMI electromagnetic signals
at their sources. The second suppression strategy
involves preventing the reception of RFI and EMIelectromagnetic signals by the audio system compo-
nents.
The use of braided ground straps in key locations
is part of the RFI and EMI prevention strategy.
These ground straps ensure adequate ground paths,
particularly for high current components such as
many of those found in the starting, charging, igni-
tion, engine control and transmission control sys-
tems. An insufficient ground path for any of these
high current components may result in radio noise
caused by induced voltages created as the high cur-
rent seeks alternative ground paths through compo-
nents or circuits intended for use by, or in close
proximity to the audio system components or circuits.
Preventing the reception of RFI and EMI is accom-
plished by ensuring that the audio system compo-
nents are correctly installed in the vehicle. Loose,
corroded or improperly soldered wire harness connec-
tions, improperly routed wiring and inadequate audio
system component grounding can all contribute to
the reception of RFI and EMI. A properly grounded
antenna body and radio chassis, as well as a shielded
antenna coaxial cable with clean and tight connec-
tions will each help reduce the potential for reception
of RFI and EMI.
REMOVAL
BED TO CAB
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the attaching bolts and strap (Fig. 10).
Fig. 10 BED TO CAB GROUND STRAP
1 - BED
2 - CAB
3 - GROUND STRAP
4 - MOUNTING BOLTS
DRAUDIO/VIDEO 8A - 9

FRONT CONTROL MODULE
DESCRIPTION
The Front Control Module (FCM) is a micro con-
troller based module located in the left front corner
of the engine compartment. On this model the inte-
grated power module must be positioned aside in
order to access the front control module. The front
control module mates to the power distribution cen-
ter to form the Integrated Power Module (IPM). The
integrated power module connects directly to the bat-
tery and provides the primary means of circuit pro-
tection and power distribution for all vehicle
electrical systems. The front control module controls
power to some of these vehicle systems electrical and
electromechanical loads based on inputs received
from hard wired switch inputs and data received on
the PCI bus circuit (J1850).
For information on theIntegrated Power Mod-
ule Refer to the Power Distribution Sectionof
the service manual.
OPERATION
As messages are sent over the PCI bus circuit, the
front control module reads these messages and con-
trols power to some of the vehicles electrical systems
by completing the circuit to ground (low side driver)
or completing the circuit to 12 volt power (high side
driver). The following functions areControlledby
the Front Control Module:
²Headlamp Power with Voltage Regulation
²Windshield Wiper ªON/OFFº Relay Actuation
²Windshield Wiper ªHI/LOº Relay Actuation
²Windshield Washer Pump Motor
²Fog Lamp Relay Actuation
²Park Lamp Relay Actuation
²Horn Relay Actuation
The following inputs areReceived/Monitoredby
the Front Control Module:
²B+ Connection Detection
²Power Ground
²Ambient Temperature Sensing
²Ignition Switch Run
²Washer Fluid Level Switch
²Windshield Wiper Park Switch
²PCI Bus Circuit
DIAGNOSIS AND TESTING - FRONT CONTROL
MODULE
The front control module is a printed circuit board
based module with a on-board micro-processor. The
front control module interfaces with other electronic
modules in the vehicle via the Programmable Com-
munications Interface (PCI) data bus (J1850). In
order to obtain conclusive testing the Programmable
Communications Interface (PCI) data bus network
and all of the electronic modules that provide inputs
to, or receive outputs from the front control module
must be checked. All PCI (J1850) communication
faults must be resolved prior to further diagnosing
any front control module related issues.
The front control module was designed to be diag-
nosed with an appropriate diagnostic scan tool, such
as the DRB IIIt. The most reliable, efficient, and
accurate means to diagnose the front control module
requires the use of a DRB IIItscan tool and the
proper Body Diagnostic Procedures manual.
Before any testing of the front control module is
attempted, the battery should be fully charged and
all wire harness and ground connections inspected
around the affected areas on the vehicle.
REMOVAL
(1) Disconnect the positive and negative battery
cables from the battery.
(2) Partially remove the integrated power module
from the engine compartment (Refer to 8 - ELECTRI-
CAL/POWER DISTRIBUTION/INTEGRATED
POWER MODULE - REMOVAL).
(3) Remove the front control module retaining
screws.
(4) Using both hands, pull the front control module
straightfrom the integrated power module assembly
to disconnect the 49-way electrical connector and
remove the front control module from the vehicle.
INSTALLATION
(1) Install the front control module on the inte-
grated power module assembly by pushing the
49-way electrical connector straight in.
(2) Install the front control module retaining
screws. Torque the screws to 7 in. lbs.
(3) Install the integrated power module (Refer to 8
- ELECTRICAL/POWER DISTRIBUTION/INTE-
GRATED POWER MODULE - INSTALLATION).
(4) Connect the positive and negative battery
cables.
DRELECTRONIC CONTROL MODULES 8E - 5

WIPERS/WASHERS
TABLE OF CONTENTS
page page
WIPERS/WASHERS
DESCRIPTION..........................1
OPERATION............................4
DIAGNOSIS AND TESTING - WIPER &
WASHER SYSTEM.....................6
CLEANING - WIPER & WASHER SYSTEM.....6
INSPECTION - WIPER & WASHER SYSTEM . . . 7
CHECK VALVE
DESCRIPTION..........................7
OPERATION............................8
REMOVAL.............................8
INSTALLATION..........................8
WASHER FLUID LEVEL SWITCH
DESCRIPTION..........................9
OPERATION............................9
REMOVAL.............................10
INSTALLATION.........................11
WASHER HOSES/TUBES
DESCRIPTION.........................11
OPERATION...........................11
WASHER NOZZLE
DESCRIPTION.........................11
OPERATION...........................12
REMOVAL.............................12
INSTALLATION.........................12
WASHER PUMP/MOTOR
DESCRIPTION.........................13
OPERATION...........................13
REMOVAL.............................14
INSTALLATION.........................14
WASHER RESERVOIR
DESCRIPTION.........................14
OPERATION...........................15
REMOVAL
REMOVAL - EXCEPT DIESEL ENGINE.....15REMOVAL - DIESEL ENGINE............16
INSTALLATION
INSTALLATION - EXCEPT DIESEL ENGINE . . 17
INSTALLATION - DIESEL ENGINE.........17
WIPER ARM
DESCRIPTION.........................17
OPERATION...........................18
REMOVAL.............................18
INSTALLATION.........................18
WIPER BLADE
DESCRIPTION.........................18
OPERATION...........................19
REMOVAL.............................19
INSTALLATION.........................20
WIPER HIGH/LOW RELAY
DESCRIPTION.........................20
OPERATION...........................20
DIAGNOSIS AND TESTING - WIPER HIGH/
LOW RELAY.........................21
REMOVAL.............................21
INSTALLATION.........................22
WIPER MODULE
DESCRIPTION.........................22
OPERATION...........................23
REMOVAL.............................23
INSTALLATION.........................23
WIPER ON/OFF RELAY
DESCRIPTION.........................24
OPERATION...........................25
DIAGNOSIS AND TESTING - WIPER ON/OFF
RELAY..............................25
REMOVAL.............................26
INSTALLATION.........................26
WIPERS/WASHERS
DESCRIPTION
An electrically operated intermittent wiper and
washer system is standard factory-installed safety
equipment on this model (Fig. 1). The wiper and
washer system includes the following major compo-
nents, which are described in further detail else-
where in this service information:
²Check Valve- The washer system check valve
is integral to the wye fitting located in the washer
plumbing between the cowl plenum washer hose andthe washer nozzles, and is concealed beneath the
cowl plenum cover/grille panel at the base of the
windshield.
²Front Control Module- The Front Control
Module (FCM) is integral to the Integrated Power
Module (IPM). The IPM is located in the engine com-
partment, near the battery. (Refer to 8 - ELECTRI-
CAL/POWER DISTRIBUTION/INTEGRATED
POWER MODULE - DESCRIPTION).
²Instrument Cluster- In this model, the instru-
ment cluster is also sometimes referred to as the Cab
Control Node (CCN). The instrument cluster is
located in the instrument panel above the steering
DRWIPERS/WASHERS 8R - 1

column opening, directly in front of the driver. (Refer
to 8 - ELECTRICAL/INSTRUMENT CLUSTER -
DESCRIPTION).
²Multi-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 control stalk that extends through
an opening on the left side of the steering column
shrouds and a control knob on the end of the stalk is
dedicated to providing all of the driver controls for
the wiper and washer systems. (Refer to 8 - ELEC-
TRICAL/LAMPS/LIGHTING - EXTERIOR/MULTI-
FUNCTION SWITCH - DESCRIPTION).
²Washer Fluid Level Switch- The washer fluid
level switch is located in a dedicated hole on the out-
board side of the washer reservoir in the engine com-
partment.²Washer Nozzle- Two fluidic washer nozzles are
secured with integral snap features to dedicated
openings in the cowl plenum cover/grille panel
located near the base of the windshield.
²Washer 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 through a trough near the
right end of the cowl plenum cover/grille panel into
the cowl plenum to the washer nozzle fittings.
²Washer Pump/Motor- The electric washer
pump/motor unit is located in a dedicated hole on the
rearward facing surface of the washer reservoir in
the engine compartment.
²Washer Reservoir- On all models except those
with an optional diesel engine, the washer reservoir
Fig. 1 Wiper & Washer System
1 - WASHER RESERVOIR, PUMP/MOTOR, FLUID LEVEL
SWITCH (EXCEPT DIESEL ENGINE)
2 - WASHER RESERVOIR, PUMP/MOTOR, FLUID LEVEL
SWITCH (DIESEL ENGINE ONLY)3 - WIPER MODULE
4 - WASHER NOZZLE (2)
5 - WIPER ARM & BLADE (2)
6 - MULTI-FUNCTION (WIPER, WASHER, & LIGHTING) SWITCH
8R - 2 WIPERS/WASHERSDR
WIPERS/WASHERS (Continued)

is secured by integral mounting tabs and a snap fea-
ture to slots in the right side of the cooling module
shroud in the engine compartment. On models with
an optional diesel engine, the washer reservoir is
secured by screws to the back of the upright left ver-
tical member of the radiator support in the engine
compartment. The washer reservoir filler neck is
accessed from the engine compartment.
²Wiper Arm- The two wiper arms are secured
with integral latches to the serrated ends of the two
wiper pivot shafts, which extend through the cowl
plenum cover/grille panel located near the base of the
windshield.
²Wiper Blade- The two 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 opera-
tion.
²Wiper High/Low Relay- The wiper high/low
relay is an International Standards Organization
(ISO) micro relay located in the Integrated Power
Module (IPM) in the engine compartment near the
battery.
²Wiper Module- The wiper pivot shafts are the
only visible components of the 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.
²Wiper On/Off Relay- The wiper on/off relay is
an International Standards Organization (ISO) micro
relay located in the Integrated Power Module (IPM)
in the engine compartment near the battery.
Hard wired circuitry connects the 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 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 appropriate wiring infor-
mation. The wiring information includes wiring dia-
grams, proper wire and connector repair procedures,
further details on wire harness routing and reten-
tion, as well as pin-out and location views for the
various wire harness connectors, splices and grounds.
OPERATING MODES
The components of the wiper and washer system
are designed to work in concert to provide the follow-
ing operating modes:²Continuous Wipe Mode- The control knob on
the control stalk of the multi-function switch has two
continuous wipe positions, Low and High. When
selected, these switch positions will cause the two-
speed wiper motor to operate in a continuous low or
high speed cycle.
²Intermittent Wipe Mode- The control knob on
the control stalk of the multi-function switch has five
minor detent intermittent wipe positions. When
selected, these switch positions will cause the wiper
system to operate with one of five delay intervals
between complete wipe cycles. The intermittent wipe
delay intervals are speed sensitive and will be dou-
bled when the vehicle speed is about sixteen kilome-
ters-per-hour (ten miles-per-hour) or less.
²Pulse Wipe Mode- When the control knob on
the control stalk of the multi-function switch is
depressed to the momentary Wash position for less
than about one-half second, the wiper system will
operate the wipers for one complete low speed cycle,
then will park the wiper blades near the base of the
windshield.
²Washer Mode- When the control knob on the
control stalk of the multi-function switch is
depressed to the momentary Wash position for more
than about one-half second with the wiper system
turned Off, the washer pump/motor and the wipers
will operate for as long as the washer switch is held
closed up to about thirty seconds, then the wipe-af-
ter-wash mode is invoked when the control knob is
released. When the Wash position is selected with
the wiper system operating in a continuous wipe
mode, washer fluid will be dispensed onto the wind-
shield glass through the washer nozzles for as long
as the washer switch is held closed up to about thirty
seconds. When the Wash position is selected with the
wiper system operating in an intermittent wipe
mode, washer fluid is still dispensed until the control
knob is released; however, the 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 interval. If the control
knob is held in the depressed Wash position for more
than about thirty seconds, washer system operation
will be suspended until the control knob is released
for about two seconds then cycled back to the Wash
position.
²Wipe-After-Wash Mode- When the control
knob on the control stalk of the multi-function switch
is depressed to the momentary Wash position for
more than about one-half second with the wiper sys-
tem turned Off, the washer pump/motor and the wip-
ers will operate for as long as the washer switch is
held closed up to about thirty seconds, then provide
several additional wipe cycles after the control knob
DRWIPERS/WASHERS 8R - 3
WIPERS/WASHERS (Continued)

is released before parking the wiper blades near the
base of the windshield. If the control knob is held in
the depressed Wash position for more than about
thirty seconds, washer system operation will be sus-
pended until the control knob is released for about
two seconds then cycled back to the Wash position.
OPERATION
The wiper and washer system is designed to pro-
vide the vehicle operator with a convenient, safe, and
reliable means of maintaining visibility through the
windshield glass. The various components of this sys-
tem 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, 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 wiper and washer
system functions with the control knob on the end of
the control stalk of the multi-function switch that
extends from the left 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 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. Depressing the control knob towards
the steering column actuates the momentary washer
system switch, which selects the Wash, Wipe-After-
Wash, and Pulse Wipe Modes depending upon when
and how long the switch is held closed. The multi-
function switch provides hard wired resistor multi-
plexed inputs to the instrument cluster for all of the
wiper and washer system functions. The instrument
cluster then sends electronic messages to the Front
Control Module (FCM) over the Programmable Com-
munications Interface (PCI) data bus requesting the
appropriate wiper and washer system operating
modes.
Wiper and washer system operation are completely
controlled by the instrument cluster and FCM logic
circuits, and that logic will only allow these systems
to operate when the ignition switch is in the Acces-
sory or On positions. Battery current is directed from
a B(+) fuse in the Integrated Power Module (IPM) to
the wiper on/off relay and the wiper high/low relay in
the IPM through a fused B(+) circuit. The FCM useslow side drivers to control wiper system operation by
energizing or de-energizing the wiper high/low and
wiper on/off relays. The FCM uses a high side driver
to control the operation of the washer pump motor
unit. The multi-function switch circuitry receives a
clean ground output from the instrument cluster on a
multi-function switch return circuit, then provides
resistor multiplexed inputs to the instrument cluster
on an intermittent wipe mux circuit to indicate the
selected wiper system mode and on a wash/beam
select mux circuit to indicate the selected washer sys-
tem mode.
The hard wired circuits and components of the
wiper and washer system may be diagnosed and
tested using conventional diagnostic tools and proce-
dures. However, conventional diagnostic methods
may not prove conclusive in the diagnosis of the
instrument cluster, the FCM, or the electronic mes-
sage inputs to or outputs from the instrument cluster
or FCM that control the wiper and washer system
operating modes. The most reliable, efficient, and
accurate means to diagnose the instrument cluster or
the FCM inputs and outputs related to the various
wiper and washer system operating modes requires
the use of a DRBIIItscan tool. Refer to the appro-
priate diagnostic information.
OPERATING MODES
Following are paragraphs that briefly describe the
operation of each of the wiper and washer system
operating modes.
CONTINUOUS WIPE MODE
When the Low position of the control knob on the
control stalk of the multi-function switch is selected
the instrument cluster sends an electronic wiper
switch low message to the FCM, then the FCM ener-
gizes the wiper on/off relay. This directs battery cur-
rent through the normally open contacts of the
energized wiper on/off relay and the normally closed
contacts of the de-energized wiper high/low relay to
the low speed brush of the wiper motor, causing the
wipers to cycle at low speed.
When the High position of the control knob is
selected the instrument cluster sends an electronic
wiper switch high message to the FCM, then the
FCM 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 wiper motor, causing the wipers to cycle
at high speed.
When the Off position of the multi-function switch
control knob is selected, the instrument cluster sends
an electronic wiper switch off message to the FCM. If
8R - 4 WIPERS/WASHERSDR
WIPERS/WASHERS (Continued)

the wiper motor was operating at high speed, the
FCM immediately de-energizes the wiper high/low
relay causing the wiper motor to return to low speed
operation. 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 wiper motor is
closed to ground and provides a hard wired park
switch sense input to the FCM. The FCM then de-en-
ergizes the wiper on/off relay and the wiper motor
ceases to operate. If the wiper blades are not in the
down position on the windshield at the moment the
Off position is selected, the park switch is an open
circuit and the FCM keeps the wiper on/off relay
energized, which 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 input to the FCM is again closed to ground.
INTERMITTENT WIPE MODE
When the control knob on the control stalk of the
multi-function switch is moved to one of the Delay
interval positions the instrument cluster sends an
electronic wiper switch delay message to the FCM,
then the FCM electronic intermittent wipe logic cir-
cuit responds by calculating the correct length of
time between wiper sweeps based upon the selected
delay interval input. The FCM monitors the changing
state of the wiper motor park switch through a hard
wired park switch sense input. This input allows the
FCM to determine the proper intervals at which to
energize and de-energize the wiper on/off relay to
operate the wiper motor intermittently for one low
speed cycle at a time.
The FCM logic is also programmed to provide vehi-
cle speed sensitivity to the selected intermittent wipe
delay intervals. In order to provide this feature the
FCM monitors electronic vehicle speed messages
from the Powertrain Control Module (PCM) and dou-
bles the selected delay interval whenever the vehicle
speed is about sixteen kilometers-per-hour (ten miles-
per-hour) or less.
PULSE WIPE MODE
When the control knob on the control stalk of the
multi-function switch is depressed to the momentary
Wash position for less than about one-half second,
the instrument cluster sends an electronic washer
switch message to the FCM, then the FCM the ener-
gizes the wiper on/off relay for one complete wipe
cycle. The FCM de-energizes the relay when the state
of the park switch sense changes to ground, parking
the wiper blades near the base of the windshield.WASH MODE
When the control knob on the control stalk of the
multi-function switch is depressed to the momentary
Wash position for more than about one-half second,
the instrument cluster sends an electronic washer
switch message to the FCM, then the FCM directs
battery current to the washer pump/motor unit. This
will cause the washer pump/motor unit to be ener-
gized for as long as the Wash switch is held closed up
to about thirty seconds, and to de-energize when the
front Wash switch is released.
When the control knob is depressed to the momen-
tary Wash position while the wiper system is operat-
ing in one of the Delay interval positions, the washer
pump/motor operation is the same. However, the
FCM also energizes the wiper on/off relay to override
the selected delay interval and operate the wiper
motor in a continuous low speed mode for as long as
the control knob is held depressed, then de-energizes
the relay and reverts to the selected delay mode
interval several wipe cycles after the control knob is
released. If the control knob is held depressed for
more than about thirty seconds, the FCM will sus-
pend washer pump/motor operation until the knob is
released for about two seconds, then cycled back to
the Wash position.
WIPE-AFTER-WASH MODE
When the control knob on the control stalk of the
multi-function switch is depressed to the momentary
Wash position for more than about one-half second
while the wiper system is not operating, the instru-
ment cluster sends an electronic washer switch mes-
sage to the FCM, then the FCM the directs battery
current to the washer pump/motor unit and energizes
the wiper on/off relay. This will cause the washer
pump/motor unit to be energized and operate the
wiper motor in a continuous low speed mode for as
long as the Wash switch is held closed up to about
thirty seconds. When the control knob is released,
the FCM de-energizes the washer pump/motor unit,
but allows the wiper motor to operate for several
additional wipe cycles before it de-energizes the
wiper on/off relay and parks the wiper blades near
the base of the windshield.
If the control knob is held depressed for more than
about thirty seconds, the FCM will suspend washer
pump/motor operation until the knob is released for
about two seconds, then cycled back to the Wash
position; however, the wipers will continue to operate
for as long as the Wash switch is held closed. The
FCM monitors the changing state of the wiper motor
park switch through a hard wired wiper park switch
sense circuit input. This input allows the FCM to
count the number of wipe cycles that occur after the
Wash switch is released, and to determine the proper
DRWIPERS/WASHERS 8R - 5
WIPERS/WASHERS (Continued)

interval at which to de-energize the wiper on/off
relay to complete the wipe-after-wash mode cycle.
DIAGNOSIS AND TESTING - WIPER &
WASHER SYSTEM
If the wiper motor operates, but the wipers do not
move on the windshield, replace the faulty wiper
module. If the washer pump/motor operates, but no
washer fluid is dispensed on the glass; or, if the wip-
ers operate, but chatter, lift, or do not clear the glass,
clean and inspect the wiper and washer system com-
ponents as required. (Refer to 8 - ELECTRICAL/
WIPERS/WASHERS - CLEANING) and (Refer to 8 -
ELECTRICAL/WIPERS/WASHERS - INSPECTION).
For diagnosis and testing of the multi-function
switch (Refer to 8 - ELECTRICAL/LAMPS/LIGHT-
ING - EXTERIOR/MULTI-FUNCTION SWITCH -
DIAGNOSIS AND TESTING). Refer to the appropri-
ate wiring information. The wiring information
includes wiring diagrams, proper wire and connector
repair procedures, details of wire harness routing
and retention, connector pin-out information and
location views for the various wire harness connec-
tors, splices and grounds.
The hard wired circuits and components of the
wiper and washer system may be diagnosed and
tested using conventional diagnostic tools and proce-
dures. However, conventional diagnostic methods
may not prove conclusive in the diagnosis of the
instrument cluster, the Front Control Module (FCM),
or the electronic message inputs to or outputs from
the instrument cluster and the FCM that control the
various wiper and washer system operating modes.
The most reliable, efficient, and accurate means to
diagnose the instrument cluster, the FCM, or the
electronic message inputs and outputs related to the
various wiper and washer system operating modes
requires the use of a DRBIIItscan tool. Refer to the
appropriate diagnostic information.
WARNING: TO AVOID PERSONAL INJURY OR
DEATH, ON VEHICLES EQUIPPED WITH AIRBAGS,
DISABLE THE SUPPLEMENTAL RESTRAINT SYS-
TEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, AIRBAG, SEAT BELT
TENSIONER, IMPACT SENSOR, OR INSTRUMENT
PANEL COMPONENT DIAGNOSIS OR SERVICE.
DISCONNECT AND ISOLATE THE BATTERY NEGA-
TIVE (GROUND) CABLE, THEN WAIT TWO MINUTES
FOR THE SYSTEM CAPACITOR TO DISCHARGE
BEFORE PERFORMING FURTHER DIAGNOSIS OR
SERVICE. THIS IS THE ONLY SURE WAY TO DIS-
ABLE THE SUPPLEMENTAL RESTRAINT SYSTEM.
FAILURE TO TAKE THE PROPER PRECAUTIONS
COULD RESULT IN ACCIDENTAL AIRBAG DEPLOY-
MENT.
CLEANING - WIPER & WASHER SYSTEM
WIPER SYSTEM
The squeegees of wiper blades exposed to the ele-
ments for a long time tend to lose their wiping effec-
tiveness. Periodic cleaning of the squeegees is
suggested to remove any deposits of salt or road film.
The wiper blades, arms, and windshield glass should
only be cleaned using a sponge or soft cloth and
windshield washer fluid, a mild detergent, or a non-
abrasive cleaner. If the wiper blades continue to
leave streaks, smears, hazing, or beading on the
glass after thorough cleaning of the squeegees and
the glass, the entire wiper blade assembly must be
replaced.
CAUTION: Protect the rubber squeegees of the
wiper blades from any petroleum-based cleaners,
solvents, or contaminants. These products can rap-
idly deteriorate the rubber squeegees.
WASHER SYSTEM
If the washer system is contaminated with foreign
material, drain the washer reservoir by removing the
washer pump/motor from the reservoir. Clean foreign
material from the inside of the washer pump/motor
inlet filter screen and the washer reservoir using
clean washer fluid, a mild detergent, or a non-abra-
sive cleaner. Flush foreign material from the washer
system plumbing by first disconnecting the washer
hoses from the washer nozzles, then running the
washer pump/motor to run clean washer fluid or
water through the system. Plugged or restricted
washer nozzles should be carefully back-flushed
using compressed air. If the washer nozzle obstruc-
tion cannot be cleared, replace the washer nozzle.
CAUTION: Never introduce petroleum-based clean-
ers, solvents, or contaminants into the washer sys-
tem. These products can rapidly deteriorate the
rubber seals and hoses of the washer system, as
well as the rubber squeegees of the wiper blades.
CAUTION: Never use compressed air to flush the
washer system plumbing. Compressed air pres-
sures are too great for the washer system plumbing
components and will result in further system dam-
age. Never use sharp instruments to clear a
plugged washer nozzle or damage to the nozzle ori-
fice and improper nozzle spray patterns will result.
8R - 6 WIPERS/WASHERSDR
WIPERS/WASHERS (Continued)

(FCM) on a sensor return circuit and the washer
fluid switch sense input to the FCM. When the
switch closes, the FCM senses the ground on the
washer fluid switch sense circuit. The FCM is pro-
grammed to respond to this input by sending an elec-
tronic washer fluid indicator lamp-on message to the
instrument cluster over the Programmable Commu-
nications Interface (PCI) data bus. The instrument
cluster responds to this message by illuminating the
washer fluid indicator and by sounding an audible
chime tone warning.
The washer fluid level switch 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
instrument cluster, the FCM, or the electronic mes-
sage inputs to or outputs from the instrument cluster
and the FCM that control the operation of the
washer fluid visual and/or audible indicators. The
most reliable, efficient, and accurate means to diag-
nose the washer fluid level indicator, the instrument
cluster, the FCM, or the electronic message inputs
and outputs related to the washer fluid indicator
requires the use of a DRBIIItscan tool. Refer to the
appropriate diagnostic information.
REMOVAL
The washer fluid level switch can be removed from
the washer reservoir without removing the reservoir
from the vehicle.
(1) Unlatch and open the hood.
(2) Disconnect and isolate the battery negative
cable.
(3) Disconnect the washer hose from the barbed
outlet nipple of the washer pump/motor unit and
allow the washer fluid to drain into a clean container
for reuse.
(4) Disconnect the right (except diesel engine) or
left (diesel engine only) headlamp and dash wire har-
ness connector for the washer fluid level switch from
the switch connector receptacle (Fig. 7) or (Fig. 8).
NOTE: The pivoting float of the washer fluid level
switch must be in a horizontal position within the
reservoir in order to be removed. With the reservoir
empty and in an upright position, the pivoting float
will orient itself to the horizontal position when the
switch connector receptacle is pointed straight
upwards.
(5) Using a trim stick or another suitable wide
flat-bladed tool, gently pry the barbed nipple of the
washer fluid level switch out of the rubber grommet
seal on the reservoir sump. Care must be taken not
to damage the reservoir.
(6) Remove the washer fluid level switch from the
washer reservoir.(7) Remove the rubber grommet seal from the
washer fluid level switch mounting hole in the
washer reservoir and discard.
Fig. 7 Washer Fluid Level Switch Remove/Install -
Except Diesel Engine
1 - WASHER HOSE
2 - WASHER RESERVOIR
3 - WASHER FLUID LEVEL SWITCH
4 - WIRE HARNESS
5 - WASHER PUMP/MOTOR
Fig. 8 Washer Fluid Level Switch Remove/Install -
Diesel Engine
1 - WIRE HARNESS
2 - WASHER RESERVOIR
3 - WASHER PUMP/MOTOR
4 - WASHER HOSE
5 - WASHER FLUID LEVEL SWITCH
8R - 10 WIPERS/WASHERSDR
WASHER FLUID LEVEL SWITCH (Continued)

INSTALLATION
(1) Install a new rubber grommet seal into the
washer fluid level switch mounting hole in the
washer reservoir. Always use a new rubber grommet
seal on the reservoir.
(2) Insert the float of the washer fluid level switch
through the rubber grommet seal and into the
washer reservoir. The connector receptacle of the
washer fluid level switch should be pointed upward.
(3) Using hand pressure, press firmly and evenly
on the washer fluid level switch mounting flange
until the barbed nipple is fully seated in the rubber
grommet seal in the washer reservoir mounting hole.
(4) Reconnect the right (except diesel engine) or
left (diesel engine only) headlamp and dash wire har-
ness connector for the washer fluid level switch to
the switch connector receptacle (Fig. 7) or (Fig. 8).
(5) Reconnect the removed washer hose to the
barbed outlet nipple of the washer pump/motor unit.
(6) Refill the washer reservoir with the washer
fluid drained from the reservoir during the removal
procedure.
(7) Reconnect the battery negative cable.
(8) Close and latch the hood.
WASHER HOSES/TUBES
DESCRIPTION
The washer plumbing consists of a small diameter
rubber reservoir washer hose that is routed from the
barbed outlet nipple of the electric washer pump/mo-tor unit on the washer reservoir through a trough
molded into the back of the reservoir above the
washer pump and to the engine compartment washer
hose (Fig. 9). On models equipped with an optional
diesel engine, the reservoir washer hose is routed
through routing clips on the top of the radiator fan
shroud from the washer reservoir on the left side of
the radiator to the engine compartment washer hose
on the right side of the radiator. The engine compart-
ment washer hose is contained within the right head-
lamp and dash wire harness, which is routed through
the engine compartment along the top of the right
front fender wheel house to the dash panel.
The engine compartment washer hose is connected
to the washer reservoir washer hose and to the cowl
plenum washer hose with molded plastic in-line fit-
tings that have a barbed nipple on each end. The
cowl plenum washer hose is routed from the engine
compartment into the cowl plenum area through a
trough formation located near the right end of the
cowl plenum cover/grille panel. The cowl plenum
washer hose is connected to the washer system check
valve/wye fitting on the underside of the cowl plenum
cover/grille panel. The cowl plenum washer hose and
the two washer nozzle hoses are routed through inte-
gral routing clips on the underside of the cowl ple-
num cover/grille panel. The cowl plenum washer hose
is connected to one nipple on the wye fitting and the
two washer nozzle hoses are connected to the other
two wye fitting nipples. The washer nozzle hoses are
then routed along 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.
OPERATION
Washer fluid in the washer reservoir is pressurized
and fed by the washer pump/motor through the
washer system plumbing and fittings to the two
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.
WASHER NOZZLE
DESCRIPTION
The two washer nozzles have integral snap fea-
tures and an anti-rotation tab that secure them in
dedicated holes in the cowl plenum cover/grille panel
located near the base of the windshield (Fig. 10). The
Fig. 9 Engine Compartment Washer Hose
1 - RIGHT FENDER
2 - RIGHT HEADLAMP & DASH WIRE HARNESS
3 - ENGINE COMPARTMENT WASHER HOSE (TO COWL
PLENUM)
4 - COWL PLENUM WASHER HOSE
5 - ENGINE COMPARTMENT WASHER HOSE (TO WASHER
RESERVOIR)
DRWIPERS/WASHERS 8R - 11
WASHER FLUID LEVEL SWITCH (Continued)