1998 DODGE RAM 1500 tow

INSTALLATION
The following procedure applies only to the rear
seat upper child tether straps used on quad cab mod-
els. The child restraint anchors used in other models
and locations are integral to other components and
cannot be serviced separately.
WARNING: TO AVOID PERSONAL INJURY OR
DEATH, DURING AND FOLLOWING ANY SEAT BELT
OR CHILD RESTRAINT ANCHOR SERVICE, CARE-
FULLY INSPECT ALL SEAT BELTS, BUCKLES,
MOUNTING HARDWARE, RETRACTORS, TETHER
STRAPS, AND ANCHORS FOR PROPER INSTALLA-
TION, OPERATION, OR DAMAGE. REPLACE ANY
BELT THAT IS CUT, FRAYED, OR TORN.
STRAIGHTEN ANY BELT THAT IS TWISTED.
TIGHTEN ANY LOOSE FASTENERS. REPLACE ANY
BELT THAT HAS A DAMAGED OR INOPERATIVE
BUCKLE OR RETRACTOR. REPLACE ANY BELT
THAT HAS A BENT OR DAMAGED LATCH PLATE
OR ANCHOR PLATE. REPLACE ANY CHILD
RESTRAINT ANCHOR OR THE UNIT TO WHICH THE
ANCHOR IS INTEGRAL THAT HAS BEEN BENT OR
DAMAGED. NEVER ATTEMPT TO REPAIR A SEAT
BELT OR CHILD RESTRAINT COMPONENT.
ALWAYS REPLACE DAMAGED OR FAULTY SEAT
BELT AND CHILD RESTRAINT COMPONENTS WITH
THE CORRECT, NEW AND UNUSED REPLACEMENT
PARTS LISTED IN THE DAIMLERCHRYSLER MOPAR
PARTS CATALOG.
(1) Position the child tether strap onto the upper
cab back panel reinforcement (Fig. 16).
(2) Install and tighten the screw that secures the
child tether strap to the upper cab back panel rein-
forcement. Tighten the screw to 14 N´m (10 ft. lbs.).(3) Reinstall the rear seat into the vehicle. (Refer
to 23 - BODY/SEATS/SEAT - REAR - INSTALLA-
TION).
CLOCKSPRING
DESCRIPTION
The clockspring assembly is secured with two
screws onto the multi-function switch mounting
housing near the top of the steering column behind
the steering wheel (Fig. 17). The clockspring consists
of a flat, round molded plastic case with a stubby tail
that hangs below the steering column (Fig. 18). The
tail contains two connector receptacles that face
toward the instrument panel. Within the plastic case
is a spool-like molded plastic rotor with a large
exposed hub. The upper surface of the rotor hub has
a large center hole, two large flats, an engagement
dowel with a yellow rubber boot, two short pigtail
wires with connectors, and two connector receptacles
that face toward the steering wheel.
The lower surface of the rotor hub has a molded
plastic turn signal cancel cam with two lobes that is
keyed to the rotor and is secured there with four
integral snap features. Within the plastic case and
wound around the rotor spool is a long ribbon-like
tape that consists of several thin copper wire leads
sandwiched between two thin plastic membranes.
The outer end of the tape terminates at the connector
Fig. 16 Child Tether Strap - Quad Cab
1 - TETHER STRAP (3)
2 - CAB BACK PANEL
3 - SCREW (3)
Fig. 17 Clockspring
1 - PIGTAIL WIRE (2)
2 - LOCATING TAB
3 - LOCKING PIN
4 - MOUNTING TAB (2)
5 - UPPER CONNECTOR RECEPTACLE (2)
6 - LABEL
7 - ENGAGEMENT DOWEL & BOOT
8 - CASE
9 - CENTERING ARROWS
10 - ROTOR
8O - 18 RESTRAINTSDR
CHILD RESTRAINT ANCHOR (Continued)

by the ACM to suit the monitored impact conditions
by providing one of three delay intervals between the
electrical signals provided to the two initiators. The
longer the delay between these signals, the less force-
fully the airbag will deploy.
When the ACM sends the proper electrical signals
to each initiator, the electrical energy generates
enough heat to initiate a small pyrotechnic charge
which, in turn ignites chemical pellets within the
inflator. Once ignited, these chemical pellets burn
rapidly and produce a large quantity of inert gas.
The inflator is sealed to the back of the airbag hous-
ing and a diffuser in the inflator directs all of the
inert gas into the airbag cushion, causing the cushion
to inflate. As the cushion inflates, the driver airbag
trim cover will split at predetermined breakout lines,
then fold back out of the way along with the horn
switch unit. Following an airbag deployment, the air-
bag cushion quickly deflates by venting the inert gas
towards the instrument panel through vent holes
within the fabric used to construct the back (steering
wheel side) panel of the airbag cushion.
Some of the chemicals used to create the inert gas
may be considered hazardous while in their solid
state before they are burned, but they are securely
sealed within the airbag inflator. Typically, both ini-
tiators are used and all potentially hazardous chem-
icals are burned during an airbag deployment event.
However, it is possible for only one initiator to be
used during a deployment due to an airbag system
fault; therefore, it is necessary to always confirm
that both initiators have been used in order to avoid
the improper disposal of potentially live pyrotechnic
or hazardous materials. (Refer to 8 - ELECTRICAL/
RESTRAINTS - STANDARD PROCEDURE - SER-
VICE AFTER A SUPPLEMENTAL RESTRAINT
DEPLOYMENT).
The inert gas that is produced when the chemicals
are burned is harmless. However, a small amount of
residue from the burned chemicals may cause some
temporary discomfort if it contacts the skin, eyes, or
breathing passages. If skin or eye irritation is noted,
rinse the affected area with plenty of cool, clean
water. If breathing passages are irritated, move to
another area where there is plenty of clean, fresh air
to breath. If the irritation is not alleviated by these
actions, contact a physician.
REMOVAL
The following procedure is for replacement of a
faulty or damaged driver airbag. If the airbag is
faulty or damaged, but not deployed, review the rec-
ommended procedures for handling non-deployed
supplemental restraints. (Refer to 8 - ELECTRICAL/
RESTRAINTS - STANDARD PROCEDURE - HAN-
DLING NON-DEPLOYED SUPPLEMENTALRESTRAINTS). If the driver airbag has been
deployed, review the recommended procedures for
service after a supplemental restraint deployment
before removing the airbag from the vehicle. (Refer to
8 - ELECTRICAL/RESTRAINTS - STANDARD PRO-
CEDURE - SERVICE AFTER A SUPPLEMENTAL
RESTRAINT DEPLOYMENT).
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.
WARNING: TO AVOID PERSONAL INJURY OR
DEATH, WHEN REMOVING A DEPLOYED AIRBAG,
RUBBER GLOVES, EYE PROTECTION, AND A
LONG-SLEEVED SHIRT SHOULD BE WORN. THERE
MAY BE DEPOSITS ON THE AIRBAG CUSHION AND
OTHER INTERIOR SURFACES. IN LARGE DOSES,
THESE DEPOSITS MAY CAUSE IRRITATION TO THE
SKIN AND EYES.
(1) Disconnect and isolate the battery negative
cable. Wait two minutes for the system capacitor to
discharge before further service.
(2) From the underside of the steering wheel,
remove the two screws that secure the driver airbag
to the steering wheel armature (Fig. 23).
(3) Pull the driver airbag away from the steering
wheel far enough to access the three electrical con-
nections on the back of the airbag housing (Fig. 24).
(4) Disconnect the steering wheel wire harness
connector for the horn switch from the horn switch
feed pigtail wire connector, which is located on the
back of the driver airbag housing.
CAUTION: Do not pull on the clockspring pigtail
wires or pry on the connector insulator to disen-
gage the connector from the driver airbag inflator
connector receptacle. Improper removal of these
pigtail wires and their connector insulators can
result in damage to the airbag circuits or connector
insulators.
8O - 24 RESTRAINTSDR
DRIVER AIRBAG (Continued)

(1) Move the right or left front outboard seat sec-
tion (40 percent) to its most rearward position and
tilt the seat back forward for easiest access to the
front outboard seat belt buckle lower anchor.
(2) For easiest access to the front outboard seat
belt buckle lower anchor on standard cab models,
also move the outboard seat section (40 percent)
opposite the side from which the buckle is to be
removed to its most forward position and tilt the seat
back forward.
(3) On standard cab models only, remove the stow-
age tray from the rear floor panel behind the seat.
(Refer to 23 - BODY/INTERIOR/REAR FLOOR
STOWAGE TRAY - REMOVAL).
(4) From behind the front seat on the driver side
only, disconnect the seat belt switch pigtail wire con-
nector from the seat wire harness take out and con-
nector for the switch located below the inboard edge
of the driver side inboard seat track just forward of
the buckle lower anchor (Fig. 33).
(5) From behind the front seat, remove the screw
that secures the front outboard seat belt buckle lower
anchor to the bracket on the inboard seat track.
(6) From the front of the front seat, reach between
the center seat cushion and the adjacent right or left
front outboard seat cushion to access and remove the
front outboard seat belt buckle from the seat.INSTALLATION
A traveling front outboard seat belt buckle is
located on the inboard side of each front outboard
seat section (40 percent) used on all models. The seat
belt buckle on the driver's side front seat for all mod-
els also includes a seat belt switch. (Refer to 8 -
ELECTRICAL/RESTRAINTS/SEAT BELT SWITCH -
DESCRIPTION).
WARNING: TO AVOID PERSONAL INJURY OR
DEATH, DURING AND FOLLOWING ANY SEAT BELT
OR CHILD RESTRAINT ANCHOR SERVICE, CARE-
FULLY INSPECT ALL SEAT BELTS, BUCKLES,
MOUNTING HARDWARE, RETRACTORS, TETHER
STRAPS, AND ANCHORS FOR PROPER INSTALLA-
TION, OPERATION, OR DAMAGE. REPLACE ANY
BELT THAT IS CUT, FRAYED, OR TORN.
STRAIGHTEN ANY BELT THAT IS TWISTED.
TIGHTEN ANY LOOSE FASTENERS. REPLACE ANY
BELT THAT HAS A DAMAGED OR INOPERATIVE
BUCKLE OR RETRACTOR. REPLACE ANY BELT
THAT HAS A BENT OR DAMAGED LATCH PLATE
OR ANCHOR PLATE. REPLACE ANY CHILD
RESTRAINT ANCHOR OR THE UNIT TO WHICH THE
ANCHOR IS INTEGRAL THAT HAS BEEN BENT OR
DAMAGED. NEVER ATTEMPT TO REPAIR A SEAT
BELT OR CHILD RESTRAINT COMPONENT.
ALWAYS REPLACE DAMAGED OR FAULTY SEAT
BELT AND CHILD RESTRAINT COMPONENTS WITH
THE CORRECT, NEW AND UNUSED REPLACEMENT
PARTS LISTED IN THE DAIMLERCHRYSLER MOPAR
PARTS CATALOG.
(1) From the front of the front seat, reach between
the center seat cushion and the adjacent right or left
front outboard seat cushion to position the front out-
board seat belt buckle to the seat (Fig. 33).
(2) From behind the front seat, install and tighten
the screw that secures the front outboard seat belt
buckle lower anchor to the bracket on the inboard
seat track. Tighten the screw to 25 N´m (18 ft. lbs.).
(3) From behind the front seat on the driver side
only, reconnect the seat belt switch pigtail wire con-
nector to the seat wire harness take out and connec-
tor for the switch located below the inboard edge of
the driver side inboard seat track just forward of the
buckle lower anchor.
(4) On standard cab models only, reinstall the
stowage tray onto the rear floor panel behind the
seat. (Refer to 23 - BODY/INTERIOR/REAR FLOOR
STOWAGE TRAY - INSTALLATION).
(5) On standard cab models, move the outboard
seat section (40 percent) opposite the side from which
the buckle was replaced to its most rearward position
and tilt the seat back to its upright position.
Fig. 33 Front Outboard Seat Belt Buckle Remove/
Install
1 - DRIVER SIDE FRONT OUTBOARD SEAT BELT BUCKLE
2 - SEAT CUSHION
3 - PIGTAIL WIRE
4 - INBOARD SEAT TRACK
5 - SCREW
8O - 38 RESTRAINTSDR
FRONT OUTBOARD SEAT BELT BUCKLE (Continued)

(5) Reach through and above the glove box opening
to access and remove the two screws that secure the
passenger airbag rear brackets to the upper glove
box opening reinforcement (Fig. 37).
(6) Reach through and above the glove box opening
to access and remove the two screws that secure the
passenger airbag front brackets to the instrument
panel structural support.
(7) Using a trim stick or another suitable wide
flat-bladed tool, gently pry the upper and outboard
edges of the passenger airbag door away from the
instrument panel far enough to disengage the seven
snap features on the door from the receptacles in the
instrument panel base trim (Fig. 38).
(8) Pull the passenger airbag housing and door
unit straight back from the instrument panel far
enough to access the instrument panel wire harness
take out and connector for the airbag located on the
inboard side of the airbag housing.(9) Disconnect the passenger airbag pigtail wire
connector from the instrument panel wire harness
connector for the airbag. To disconnect the connector:
(a) Slide the red Connector Position Assurance
(CPA) lock on the connector toward the side of the
connector.
(b) Depress the connector latch tab and pull the
two halves of the connector straight away from
each other.
(10) Remove the passenger airbag and airbag door
from the instrument panel as a unit.
INSTALLATION
The following procedure is for replacement of a
faulty or damaged passenger airbag. If the airbag is
faulty or damaged, but not deployed, review the rec-
ommended procedures for handling non-deployed
supplemental restraints. (Refer to 8 - ELECTRICAL/
RESTRAINTS - STANDARD PROCEDURE - HAN-
DLING NON-DEPLOYED SUPPLEMENTAL
RESTRAINTS). If the passenger airbag has been
deployed, review the recommended procedures for
service after a supplemental restraint deployment
before removing the airbag from the vehicle. (Refer to
8 - ELECTRICAL/RESTRAINTS - STANDARD PRO-
CEDURE - SERVICE AFTER A SUPPLEMENTAL
RESTRAINT DEPLOYMENT).
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.
WARNING: TO AVOID PERSONAL INJURY OR
DEATH, WHEN REMOVING A DEPLOYED AIRBAG,
RUBBER GLOVES, EYE PROTECTION, AND A
LONG-SLEEVED SHIRT SHOULD BE WORN. THERE
MAY BE DEPOSITS ON THE AIRBAG UNIT AND
OTHER INTERIOR SURFACES. IN LARGE DOSES,
THESE DEPOSITS MAY CAUSE IRRITATION TO THE
SKIN AND EYES.
Fig. 37 Passenger Airbag Remove/Install
1 - PASSENGER AIRBAG DOOR
2 - UPPER GLOVE BOX OPENING REINFORCEMENT
3 - FRONT BRACKET SCREW (2)
4 - REAR BRACKET SCREW (2)
Fig. 38 Passenger Airbag Door Disengage
1 - TRIM STICK
2 - PASSENGER AIRBAG DOOR
3 - INSTRUMENT PANEL
DRRESTRAINTS 8O - 41
PASSENGER AIRBAG (Continued)

(8) Install and tighten the screw that secures the
seat belt turning loop to the C-pillar. Tighten the
screw to 40 N´m (29 ft. lbs.).
(9) Engage the lower snap features of the new trim
cover over the rear outboard seat belt turning loop
and, using hand pressure, press firmly and evenly on
the top of the trim cover until it snaps into place.
(10) Position the lower seat belt anchor to the base
of the inner C-pillar.
(11) Install and tighten the screw that secures the
lower seat belt anchor to the base of the inner C-pil-
lar. Tighten the screw to 40 N´m (29 ft. lbs.).
(12) Reinstall the rear seat into the vehicle. (Refer
to 23 - BODY/SEATS/SEAT - REAR - INSTALLA-
TION).
REAR SEAT BELT BUCKLE
REMOVAL
REMOVAL - CENTER & LEFT OUTBOARD
WARNING: TO AVOID PERSONAL INJURY OR
DEATH, DURING AND FOLLOWING ANY SEAT BELT
OR CHILD RESTRAINT ANCHOR SERVICE, CARE-
FULLY INSPECT ALL SEAT BELTS, BUCKLES,
MOUNTING HARDWARE, RETRACTORS, TETHER
STRAPS, AND ANCHORS FOR PROPER INSTALLA-
TION, OPERATION, OR DAMAGE. REPLACE ANY
BELT THAT IS CUT, FRAYED, OR TORN.
STRAIGHTEN ANY BELT THAT IS TWISTED.
TIGHTEN ANY LOOSE FASTENERS. REPLACE ANY
BELT THAT HAS A DAMAGED OR INOPERATIVE
BUCKLE OR RETRACTOR. REPLACE ANY BELT
THAT HAS A BENT OR DAMAGED LATCH PLATE
OR ANCHOR PLATE. REPLACE ANY CHILD
RESTRAINT ANCHOR OR THE UNIT TO WHICH THE
ANCHOR IS INTEGRAL THAT HAS BEEN BENT OR
DAMAGED. NEVER ATTEMPT TO REPAIR A SEAT
BELT OR CHILD RESTRAINT COMPONENT.
ALWAYS REPLACE DAMAGED OR FAULTY SEAT
BELT AND CHILD RESTRAINT COMPONENTS WITH
THE CORRECT, NEW AND UNUSED REPLACEMENT
PARTS LISTED IN THE DAIMLERCHRYSLER MOPAR
PARTS CATALOG.(1) Lift up the rear seat cushion into its stowed
position against the rear seat back.
(2) Remove the screw that secures either the cen-
ter or the left outboard occupant buckle unit to the
rear floor panel near the base of the cab back panel
(Fig. 44). On models with the optional 60/40 split
rear bench, the screw that secures the buckle unit
also secures one of the rear seat mounting brackets
to the rear floor panel.
(3) Remove the center or the left outboard occu-
pant buckle unit from the rear floor panel or from
the rear seat mounting bracket.
Fig. 44 Rear Seat Belt Buckle Remove/Install
1 - CAB BACK PANEL
2 - CENTER SEAT BELT RETRACTOR
3 - SCREW (4)
4 - LEFT OUTBOARD OCCUPANT BUCKLE UNIT
5 - CENTER OCCUPANT BUCKLE UNIT
6 - CENTER ANCHOR/RIGHT OUTBOARD OCCUPANT BUCKLE
& BRACKET UNIT
7 - REAR FLOOR PANEL
8O - 48 RESTRAINTSDR
REAR OUTBOARD SEAT BELT & RETRACTOR (Continued)

CABLE
DESCRIPTION
The speed control servo cable is connected between
the speed control vacuum servo diaphragm and the
throttle body control linkage. This cable is used with
3.7L/4.7L gas powered engines only. It is also used if
equipped with a 5.9L diesel engine equipped with an
automatic transmission.
A speed control servo cableis not usedif equipped
with either a 5.9L diesel engine equipped with a
manual transmission, or any 5.7L engine/transmis-
sion combinations.
OPERATION
This cable causes the throttle control linkage to
open or close the throttle valve in response to move-
ment of the vacuum servo diaphragm.
REMOVAL
3.7L / 4.7L GAS
(1) Disconnect negative battery cable at battery.
(2) Remove air intake tube at top of throttle body.
The accelerator cable must be partially removed to
gain access to speed control cable.
(3) Hold throttle in wide open position. While held
in this position, slide throttle cable pin (Fig. 1) from
throttle body bellcrank.
(4) Using a pick or small screwdriver, press release
tab (Fig. 2) to release plastic cable mount from
bracket.Press on tab only enough to release
cable from bracket. If tab is pressed too much,
it will be broken.Slide plastic mount (Fig. 2)
towards right side of vehicle to remove throttle cable
from throttle body bracket.
(5) Using finger pressure only, disconnect servo
cable connector (Fig. 3) at throttle body bellcrank pin
by pushing connector off bellcrank pin towards front
of vehicle.DO NOT try to pull connector off per-
pendicular to the bellcrank pin. Connector will
be broken.
(6) Slide speed control cable plastic mount towards
right of vehicle to remove cable from throttle body
bracket (Fig. 4).
(7) Remove servo cable from servo. Refer to Servo
Removal/Installation.
5.9L Diesel Ð Auto. Trans.
(1) Disconnect both negative battery cables at both
batteries.
(2) Remove cable/lever/linkage cover. Refer to
Speed Control Servo Removal/Installation.
(3) Remove (disconnect) servo cable from servo.
Refer to Speed Control Servo Removal/Installation.(4) Using finger pressure only, disconnect end of
servo cable from throttle lever pin by pulling forward
on connector while holding lever rearward (Fig. 5).
DO NOT try to pull connector off perpendicular
to lever pin. Connector will be broken.
(5) Squeeze 2 pinch tabs (Fig. 5) on sides of speed
control cable at mounting bracket and push cable
rearward out of bracket.
Fig. 1 THROTTLE CABLE PIN - 3.7L / 4.7L
1 - THROTTLE CABLE PIN
2 - THROTTLE BODY BELLCRANK
3 - PUSH UP HERE
Fig. 2 THROTTLE CABLE RELEASE TAB - 3.7L /
4.7L
1 - THROTTLE CABLE
2 - RELEASE TAB
3 - PICK OR SCREWDRIVER
4 - PLASTIC CABLE MOUNT
8P - 4 SPEED CONTROLDR

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)

washer system plumbing (Fig. 3). The check valve is
integral to the washer nozzle plumbing wye fitting
located in the cowl plenum area beneath the cowl
plenum cover/grille panel near the base of the wind-
shield. The check valve consists of a molded plastic
body with a raised arrowhead molded into its center
section that indicates the direction of the flow
through the valve, and three barbed hose nipples
formed in a wye configuration on the outside circum-
ference of the center section of the valve body. The
check valve cannot be adjusted or repaired and, if
faulty or damaged, it must be replaced.
OPERATION
The check valve provides more than one function
in this application. It serves as a wye connector fit-
ting between the engine compartment and washer
nozzle sections of the washer supply hose. It prevents
washer fluid from draining out of the washer supply
hoses back to the washer reservoir. This drain-back
would result in a lengthy delay from when the
washer switch is actuated until washer fluid was dis-
pensed through the washer nozzles, because the
washer pump would have to refill the washer plumb-
ing from the reservoir to the nozzles. Such a drain-
back condition could also result in water, dirt, or
other outside contaminants being siphoned into the
washer system through the washer nozzle orifice.
This water could subsequently freeze and plug the
nozzle, while other contaminants could interfere with
proper nozzle operation and cause improper nozzle
spray patterns. In addition, the check valve prevents
washer fluid from siphoning through the washer noz-
zles after the washer system is turned Off.When the washer pump pressurizes and pumps
washer fluid from the reservoir through the washer
plumbing, the fluid pressure unseats a diaphragm
from over a sump well within the valve by overriding
the spring pressure applied to it by a piston (Fig. 4).
With the diaphragm unseated, washer fluid is
allowed to flow toward the two washer nozzles. When
the washer pump stops operating, the spring pres-
sure on the piston seats the diaphragm over the
sump well in the valve and fluid flow in either direc-
tion within the washer plumbing is prevented. The
check valve cannot be adjusted or repaired and, if
faulty or damaged, it must be replaced.REMOVAL
(1) Remove both wiper arms from the wiper pivots.
(Refer to 8 - ELECTRICAL/WIPERS/WASHERS/
WIPER ARM - REMOVAL).
(2) Unlatch and open the hood.
(3) Remove the cowl plenum cover/grille panel
from over the cowl plenum. (Refer to 23 - BODY/EX-
TERIOR/COWL GRILLE - REMOVAL).
(4) From the underside of the cowl plenum cover/
grille panel, disconnect the cowl plenum and washer
nozzle hoses from the three barbed nipples of the
check valve (Fig. 5).
(5) Remove the check valve from the underside of
the cowl plenum cover/grille panel.
INSTALLATION
(1) Position the check valve to the underside of the
cowl plenum cover/grille panel (Fig. 5). Be certain
that the flow direction arrow molded into the check
valve body is oriented towards the washer nozzles.
Fig. 3 Check Valve
1 - INLET NIPPLE
2 - CHECK VALVE
3 - OUTLET NIPPLE (2)
4 - FLOW DIRECTION ARROW
Fig. 4 Check Valve
1 - SPRING
2 - PISTON
3 - DIAPHRAGM
4 - TO WASHER NOZZLE
5 - FROM WASHER PUMP
8R - 8 WIPERS/WASHERSDR
CHECK VALVE (Continued)