1998 DODGE RAM 1500 Wiring diagrams

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)

The wiper high/low relay can be diagnosed using
conventional diagnostic tools and methods. However,
conventional diagnostic methods may not prove con-
clusive in the diagnosis of the instrument cluster, the
Front Control Module (FCM), or the electronic mes-
sage inputs to or outputs from the instrument cluster
and the FCM that control the operation of the wiper
high/low relay. The most reliable, efficient, and accu-
rate means to diagnose the wiper high/low relay, the
instrument cluster, the FCM, or the electronic mes-
sage inputs and outputs related to the wiper high/low
relay operation requires the use of a DRBIIItscan
tool. Refer to the appropriate diagnostic information.
DIAGNOSIS AND TESTING - WIPER HIGH/LOW
RELAY
The wiper high/low relay (Fig. 23) is located in the
Integrated Power Module (IPM) in the engine com-
partment near the battery. Refer to the appropriate
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 connectors, splices
and grounds.
(1) Remove the wiper high/low relay from the IPM.
(Refer to 8 - ELECTRICAL/WIPERS/WASHERS/
WIPER HIGH/LOW RELAY - REMOVAL).
(2) A relay in the de-energized position should
have continuity between terminals 87A and 30, and
no continuity between terminals 87 and 30. If OK, go
to Step 3. If not OK, replace the faulty relay.
(3) Resistance between terminals 85 and 86 (elec-
tromagnet) should be 75   8 ohms. If OK, go to Step
4. If not OK, replace the faulty relay.(4) Connect a battery to terminals 85 and 86.
There should now be continuity between terminals
30 and 87, and no continuity between terminals 87A
and 30. If OK, reinstall the relay and use a DRBIIIt
scan tool to perform further testing. Refer to the
appropriate diagnostic information.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the cover from the Integrated Power
Module (IPM) (Fig. 24).
(3) Remove the wiper high/low relay by grasping it
firmly and pulling it straight out from the receptacle
in the IPM.
Fig. 23 ISO Micro Relay
30 - COMMON FEED
85 - COIL GROUND
86 - COIL BATTERY
87 - NORMALLY OPEN
87A - NORMALLY CLOSED
Fig. 24 Integrated Power Module
1 - 15 - CARTRIDGE FUSE
16 - 53 - BLADE FUSE
54 - HEATED MIRROR RELAY
55 - WIPER ON/OFF RELAY
56 - A/C CONDENSER FAN RELAY
57 - ENGINE CONTROL RELAY
58 - FUEL PUMP RELAY
59 - TRANSMISSION RELAY
60 - WIPER HIGH/LOW RELAY
61 - SPARE
62 - FOG LAMP RELAY
63 - ADJUSTABLE PEDAL RELAY
64 - A/C CLUTCH RELAY
65 - SPARE
66 - O2 RELAY
67 - SPARE
68 - SPARE
69 - SPARE
70 - SPARE
71 - SPARE
72 - STARTER RELAY
73 - PARK LAMP RELAY
DRWIPERS/WASHERS 8R - 21
WIPER HIGH/LOW RELAY (Continued)

The wiper on/off relay cannot be adjusted or
repaired and, if faulty or damaged, the unit must be
replaced.
OPERATION
The wiper on/off relay is an electromechanical
switch that uses a low current input from the Front
Control Module (FCM) to control a high current out-
put to the wiper motor. The movable common feed
contact point is held against the fixed normally
closed contact point by spring pressure. When the
relay coil is energized, an electromagnetic field is
produced by the coil windings. This electromagnetic
field draws the movable relay contact point away
from the fixed normally closed contact point, and
holds it against the fixed normally open contact
point. When the relay coil is de-energized, spring
pressure returns the movable contact point back
against the fixed normally closed contact point. A
resistor is connected in parallel with the relay coil in
the relay, and helps to dissipate voltage spikes and
electromagnetic interference that can be generated as
the electromagnetic field of the relay coil collapses.
The wiper on/off relay terminals are connected to
the vehicle electrical system through a connector
receptacle in the Integrated Power Module (IPM).
The inputs and outputs of the wiper on/off relay
include:
²Common Feed Terminal- The common feed
terminal (30) is connected to the common feed termi-
nal of the wiper high/low relay at all times through
the wiper on/off relay output circuit.
²Coil Ground Terminal- The coil ground termi-
nal (85) is connected to a control output of the Front
Control Module (FCM) through a wiper on/off relay
control circuit. The FCM controls wiper motor opera-
tion by controlling a ground path through this cir-
cuit.
²Coil Battery Terminal- The coil battery ter-
minal (86) receives battery current at all times from
a fuse in the IPM through a fused ignition switch
output (run-acc) circuit.
²Normally Open Terminal- The normally open
terminal (87) receives battery current at all times
from a fuse in the IPM through a fused ignition
switch output (run-acc) circuit, and provides battery
current to the wiper on/off relay output circuit when-
ever the relay is energized.²Normally Closed Terminal- The normally
closed terminal (87A) is connected to ground at all
times through a take out of the left headlamp and
dash wire harness with an eyelet terminal connector
that is secured by a screw to the front end sheet
metal, and is connected to the wiper on/off relay out-
put circuit whenever the relay is de-energized.
The wiper on/off relay may be diagnosed using con-
ventional diagnostic tools and methods. However,
conventional diagnostic methods may not prove con-
clusive in the diagnosis of the instrument cluster, the
Front Control Module (FCM), or the electronic mes-
sage inputs to or outputs from the instrument cluster
and the FCM that control the operation of the wiper
on/off relay. The most reliable, efficient, and accurate
means to diagnose the wiper on/off relay, the instru-
ment cluster, the FCM, or the electronic message
inputs and outputs related to the wiper on/off relay
operation requires the use of a DRBIIItscan tool.
Refer to the appropriate diagnostic information.
DIAGNOSIS AND TESTING - WIPER ON/OFF
RELAY
The wiper on/off relay (Fig. 28) is located in the
Integrated Power Module (IPM) in the engine com-
partment near the battery. Refer to the appropriate
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 connectors, splices
and grounds.
Fig. 28 ISO Micro Relay
30 - COMMON FEED
85 - COIL GROUND
86 - COIL BATTERY
87 - NORMALLY OPEN
87A - NORMALLY CLOSED
DRWIPERS/WASHERS 8R - 25
WIPER ON/OFF RELAY (Continued)

8W-01 WIRING DIAGRAM INFORMATION
TABLE OF CONTENTS
page page
WIRING DIAGRAM INFORMATION
DESCRIPTION
DESCRIPTION - HOW TO USE WIRING
DIAGRAMS...........................1
DESCRIPTION - CIRCUIT INFORMATION....5
DESCRIPTION - CIRCUIT FUNCTIONS......6
DESCRIPTION - SECTION IDENTIFICATION
AND INFORMATION....................6
DESCRIPTION - CONNECTOR, GROUND
AND SPLICE INFORMATION..............7
WARNING
WARNINGS - GENERAL.................7
DIAGNOSIS AND TESTING - WIRING
HARNESS............................7
STANDARD PROCEDURE
STANDARD PROCEDURE -
ELECTROSTATIC DISCHARGE (ESD)
SENSITIVE DEVICES...................8
STANDARD PROCEDURE - TESTING OF
VOLTAGE POTENTIAL...................9
STANDARD PROCEDURE - TESTING FOR
CONTINUITY..........................9STANDARD PROCEDURE - TESTING FOR A
SHORT TO GROUND...................9
STANDARD PROCEDURE - TESTING FOR A
SHORT TO GROUND ON FUSES
POWERING SEVERAL LOADS...........10
STANDARD PROCEDURE - TESTING FOR A
VOLTAGE DROP......................10
SPECIAL TOOLS
WIRING/TERMINAL....................10
CONNECTOR
REMOVAL.............................11
INSTALLATION.........................11
DIODE
REMOVAL.............................14
INSTALLATION.........................14
TERMINAL
REMOVAL.............................14
INSTALLATION.........................14
WIRE
STANDARD PROCEDURE - WIRE SPLICING . . 15
WIRING DIAGRAM
INFORMATION
DESCRIPTION
DESCRIPTION - HOW TO USE WIRING
DIAGRAMS
DaimlerChrysler Corporation wiring diagrams are
designed to provide information regarding the vehi-
cles wiring content. In order to effectively use the
wiring diagrams to diagnose and repair
DaimlerChrysler Corporation vehicles, it is important
to understand all of their features and characteris-
tics.
Diagrams are arranged such that the power (B+)
side of the circuit is placed near the top of the page,
and the ground (B-) side of the circuit is placed near
the bottom of the page (Fig. 1).
All switches, components, and modules are shown
in the at rest position with the doors closed and the
key removed from the ignition (Fig. 2).Components are shown two ways. A solid line
around a component indicates that the component is
complete. A dashed line around the component indi-
cates that the component is being shown is not com-
plete. Incomplete components have a reference
number to indicate the page where the component is
shown complete.
It is important to realize that no attempt is made
on the diagrams to represent components and wiring
as they appear on the vehicle. For example, a short
piece of wire is treated the same as a long one. In
addition, switches and other components are shown
as simply as possible, with regard to function only.
SYMBOLS
International symbols are used throughout the wir-
ing diagrams. These symbols are consistent with
those being used around the world (Fig. 3).
DR8W-01 WIRING DIAGRAM INFORMATION 8W - 01 - 1

TERMINOLOGY
This is a list of terms and definitions used in the
wiring diagrams.
LHD.................Left Hand Drive Vehicles
RHD ...............Right Hand Drive Vehicles
ATX . . Automatic Transmissions-Front Wheel Drive
MTX . . . Manual Transmissions-Front Wheel Drive
AT....Automatic Transmissions-Rear Wheel Drive
MT .....Manual Transmissions-Rear Wheel Drive
SOHC...........Single Over Head Cam Engine
DOHC..........Double Over Head Cam Engine
Export . . Vehicles Built For Sale In Markets Other
Than North America
Except Export.... Vehicles Built For Sale In North
America
DESCRIPTION - CIRCUIT INFORMATION
Each wire shown in the diagrams contains a code
which identifies the main circuit, part of the main
circuit, gage of wire, and color (Fig. 4).
WIRE COLOR CODE CHART
COLOR CODE COLOR
BL BLUE
BK BLACK
BR BROWN
DB DARK BLUE
DG DARK GREEN
GY GRAY
LB LIGHT BLUE
LG LIGHT GREEN
OR ORANGE
PK PINK
RD RED
TN TAN
VT VIOLET
WT WHITE
YL YELLOW
* WITH TRACER
Fig. 4 WIRE CODE IDENTIFICATION
1 - COLOR OF WIRE (LIGHT BLUE WITH YELLOW TRACER
2 - GAGE OF WIRE (18 GAGE)
3 - PART OF MAIN CIRCUIT (VARIES DEPENDING ON
EQUIPMENT)
4 - MAIN CIRCUIT IDENTIFICATION
DR8W-01 WIRING DIAGRAM INFORMATION 8W - 01 - 5
WIRING DIAGRAM INFORMATION (Continued)

DESCRIPTION - CIRCUIT FUNCTIONS
All circuits in the diagrams use an alpha/numeric
code to identify the wire and it's function. To identify
which circuit code applies to a system, refer to the
Circuit Identification Code Chart. This chart shows
the main circuits only and does not show the second-
ary codes that may apply to some models.
CIRCUIT IDENTIFICATION CODE CHART
CIRCUIT FUNCTION
A BATTERY FEED
B BRAKE CONTROLS
C CLIMATE CONTROLS
D DIAGNOSTIC CIRCUITS
E DIMMING ILLUMINATION
CIRCUITS
F FUSED CIRCUITS
G MONITORING CIRCUITS
(GAUGES)
H OPEN
I NOT USED
J OPEN
K POWERTRAIN CONTROL
MODULE
L EXTERIOR LIGHTING
M INTERIOR LIGHTING
N NOT USED
O NOT USED
P POWER OPTION (BATTERY
FEED)
Q POWER OPTIONS (IGNITION
FEED)
R PASSIVE RESTRAINT
S SUSPENSION/STEERING
T TRANSMISSION/TRANSAXLE/
TRANSFER CASE
U OPEN
V SPEED CONTROL, WIPER/
WASHER
W OPEN
X AUDIO SYSTEMS
Y OPEN
Z GROUNDS
DESCRIPTION - SECTION IDENTIFICATION AND
INFORMATION
The wiring diagrams are grouped into individual
sections. If a component is most likely found in a par-
ticular group, it will be shown complete (all wires,
connectors, and pins) within that group. For exam-
ple, the Auto Shutdown Relay is most likely to be
found in Group 30, so it is shown there complete. It
can, however, be shown partially in another group if
it contains some associated wiring.
Splice diagrams in Section 8W-70 show the entire
splice and provide references to other sections the
splices serves. Section 8W-70 only contains splice dia-
grams that are not shown in their entirety some-
where else in the wiring diagrams.
Section 8W-80 shows each connector and the cir-
cuits involved with that connector. The connectors
are identified using the name/number on the dia-
gram pages.
WIRING SECTION CHART
GROUP TOPIC
8W-01 thru
8W-09General information and Diagram
Overview
8W-10 thru
8W-19Main Sources of Power and
Vehicle Grounding
8W-20 thru
8W-29Starting and Charging
8W-30 thru
8W-39Powertrain/Drivetrain Systems
8W-40 thru
8W-49Body Electrical items and A/C
8W-50 thru
8W-59Exterior Lighting, Wipers and
Trailer Tow
8W-60 thru
8W-69Power Accessories
8W-70 Splice Information
8W-80 Connector Pin Outs
8W-91 Connector, Ground and Splice
Locations
8W - 01 - 6 8W-01 WIRING DIAGRAM INFORMATIONDR
WIRING DIAGRAM INFORMATION (Continued)

²Ohmmeter - Used to check the resistance
between two points of a circuit. Low or no resistance
in a circuit means good continuity.
CAUTION: Most of the electrical components used
in today's vehicles are Solid State. When checking
resistance in these circuits use a meter with a 10 -
megohm or greater impedance rating. In addition,
make sure the power is disconnected from the cir-
cuit. Circuits that are powered up by the vehicle's
electrical system can cause damage to the equip-
ment and provide false readings.
²Probing Tools - These tools are used for probing
terminals in connectors (Fig. 5). Select the proper
size tool from Special Tool Package 6807, and insert
it into the terminal being tested. Use the other end
of the tool to insert the meter probe.
INTERMITTENT AND POOR CONNECTIONS
Most intermittent electrical problems are caused
by faulty electrical connections or wiring. It is also
possible for a sticking component or relay to cause a
problem. Before condemning a component or wiring
assembly, check the following items.
²Connectors are fully seated
²Spread terminals, or terminal push out
²
Terminals in the wiring assembly are fully seated
into the connector/component and locked into position
²Dirt or corrosion on the terminals. Any amount
of corrosion or dirt could cause an intermittent prob-
lem
²Damaged connector/component casing exposing
the item to dirt or moisture
²Wire insulation that has rubbed through causing
a short to ground
²Some or all of the wiring strands broken inside
of the insulation
²Wiring broken inside of the insulation
TROUBLESHOOTING WIRING PROBLEMS
When troubleshooting wiring problems there are
six steps which can aid in the procedure. The steps
are listed and explained below. Always check for non-factory items added to the vehicle before doing any
diagnosis. If the vehicle is equipped with these items,
disconnect them to verify these add-on items are not
the cause of the problem.
(1) Verify the problem.
(2) Verify any related symptoms. Do this by per-
forming operational checks on components that are
in the same circuit. Refer to the wiring diagrams.
(3) Analyze the symptoms. Use the wiring dia-
grams to determine what the circuit is doing, where
the problem most likely is occurring and where the
diagnosis will continue.
(4) Isolate the problem area.
(5) Repair the problem area.
(6) Verify the proper operation. For this step,
check for proper operation of all items on the
repaired circuit. Refer to the wiring diagrams.
STANDARD PROCEDURE
STANDARD PROCEDURE - ELECTROSTATIC
DISCHARGE (ESD) SENSITIVE DEVICES
All ESD sensitive components are solid state and a
symbol (Fig. 6) is used to indicate this. When han-
dling any component with this symbol, comply with
the following procedures to reduce the possibility of
electrostatic charge build up on the body and inad-
vertent discharge into the component. If it is not
known whether the part is ESD sensitive, assume
that it is.
(1) Always touch a known good ground before han-
dling the part. This should be repeated while han-
dling the part and more frequently after sliding
across a seat, sitting down from a standing position,
or walking a distance.
(2) Avoid touching electrical terminals of the part,
unless instructed to do so by a written procedure.
(3) When using a voltmeter, be sure to connect the
ground lead first.
(4) Do not remove the part form it's protective
packing until it is time to install the part.
(5) Before removing the part from it's pakage,
ground the pakage to a known good ground on the
vehicle.
Fig. 5 PROBING TOOL
1 - SPECIAL TOOL 6801
2 - PROBING END
Fig. 6 ELECTROSTATIC DISCHARGE SYMBOL
8W - 01 - 8 8W-01 WIRING DIAGRAM INFORMATIONDR
WIRING DIAGRAM INFORMATION (Continued)

STANDARD PROCEDURE - TESTING FOR A
SHORT TO GROUND ON FUSES POWERING
SEVERAL LOADS
(1) Refer to the wiring diagrams and disconnect or
isolate all items on the suspected fused circuits.
(2) Replace the blown fuse.
(3) Supply power to the fuse by turning ON the
ignition switch or re-connecting the battery.
(4) Start connecting or energizing the items in the
fuse circuit one at a time. When the fuse blows the
circuit with the short to ground has been isolated.
STANDARD PROCEDURE - TESTING FOR A
VOLTAGE DROP
(1) Connect the positive lead of the voltmeter to
the side of the circuit closest to the battery (Fig. 9).
(2) Connect the other lead of the voltmeter to the
other side of the switch, component or circuit.
(3) Operate the item.
(4) The voltmeter will show the difference in volt-
age between the two points.
SPECIAL TOOLS
WIRING/TERMINAL
Fig. 9 TESTING FOR VOLTAGE DROP
PROBING TOOL PACKAGE 6807
TERMINAL PICK TOOL SET 6680
TERMINAL REMOVING TOOLS 6932 AND 8638
TERMINAL REMOVING TOOL 6934
8W - 01 - 10 8W-01 WIRING DIAGRAM INFORMATIONDR
WIRING DIAGRAM INFORMATION (Continued)