1998 DODGE RAM 1500 Body

REMOVAL - WITHOUT CARGO BOX
(1) Disconnect and isolate the negative battery
cable.
(2) Disconnect the body wire harness connector
from the tail lamp wire harness connector (Fig. 22).
(3) Remove the tail lamp unit connector from the
frame rail.
(4) Remove the two nuts that secure the tail lamp
housing to the mounting bracket.
(5) Remove the tail lamp unit from the mounting
bracket while routing the wire harness through the
bracket.
INSTALLATION
INSTALLATION - WITH CARGO BOX
(1) Connect the body wire harness connector to the
lamp back plate connector.
(2) Position the tail lamp unit into the cargo box.(3) Install the two screws that secure the tail lamp
unit to the cargo box.
(4) Raise the tailgate.
(5) Reconnect the negative battery cable.
INSTALLATION - WITHOUT CARGO BOX
(1) Position the tail lamp unit onto the mounting
bracket while routing the wire harness through the
bracket.
(2) Install the two nuts that secure the tail lamp
housing to the mounting bracket.
(3) Connect the tail lamp wire harness connector
to the body wire harness connector.
(4) Install the tail lamp connector retainer to the
frame rail.
(5) Reconnect the negative battery cable.
Fig. 21 Tail Lamp Unit
1 - SCREW (2)
2 - WIRE HARNESS CONNECTOR
3 - TAIL LAMP UNIT
Fig. 22 Tail Lamp Unit - RH Side Shown, LH Side
Typical
1 - TAIL LAMP UNIT
2 - MOUNTING BRACKET
3 - TRAILER HITCH BRACKET
4 - WIRE HARNESS
5 - NUT (2)
DRLAMPS/LIGHTING - EXTERIOR 8L - 23
TAIL LAMP UNIT (Continued)

TRAILER TOW WIRING
DESCRIPTION
Vehicles equipped with an optional factory-in-
stalled trailer towing package have a rear body wire
harness that includes an integral trailer tow wiring
take out that connects to a heavy duty, sealed, 7-pin
trailer tow connector located in the rear bumper (Fig.
23). This harness includes an adapter harness that
adapts the 7-pin trailer tow connector to a standard,
light-duty, 4-pin trailer tow connector. Refer to the
appropriate wiring information.
TURN LAMP
REMOVAL
REMOVAL - WITH CARGO BOX
(1) Disconnect and isolate the negative battery
cable.
(2) Remove the tail lamp unit (Refer to 8 - ELEC-
TRICAL/LAMPS/LIGHTING - EXTERIOR/TAIL
LAMP UNIT - REMOVAL).
(3) Remove the lamp back plate from the tail lamp
unit.
(4) Release the turn signal bulb locking tabs and
remove the bulb from the back plate.
REMOVAL - WITHOUT CARGO BOX
(1) Disconnect and isolate the negative battery
cable.(2) Remove the four screws that secure the tail
lamp lens to the tail lamp housing (Fig. 24).
(3) Separate the tail lamp lens from the tail lamp
housing.
(4) Push the turn signal bulb inward and rotate it
counter-clockwise.
(5) Remove the turn signal bulb from the tail lamp
socket.
INSTALLATION
INSTALLATION - WITH CARGO BOX
(1) Install the turn signal bulb into the lamp back
plate.
(2) Install the lamp back plate onto the tail lamp
unit.
(3) Install the tail lamp unit (Refer to 8 - ELEC-
TRICAL/LAMPS/LIGHTING - EXTERIOR/TAIL
LAMP UNIT - INSTALLATION).
(4) Reconnect the negative battery cable.
INSTALLATION - WITHOUT CARGO BOX
(1) Install the turn signal bulb into the tail lamp
socket by pushing inward and rotating it clockwise.
NOTE: Install the tail lamp lens with the clear por-
tion (back-up lens) at the top of the housing. Make
sure that the gasket is correctly in place and not
twisted or torn.
(2) Position the tail lamp lens and gasket onto the
tail lamp unit.
NOTE: Do not overtighten the tail lamp lens screws
or damage to the tail lamp lens may result.
(3) Install the four screws that secure the tail
lamp lens to the tail lamp unit. Tighten the screws
securely.
(4) Reconnect the negative battery cable.
Fig. 23 Trailer Tow Wiring
1 - RETAINER CLIP (4)
2 - REAR BODY HARNESS (TRAILER TOW TAKE OUT)
3 - RETAINER CLIP (2)
4 - WIRE HARNESS CONNECTOR
Fig. 24 Tail Lamp Lens
8L - 24 LAMPS/LIGHTING - EXTERIORDR

LAMPS/LIGHTING - INTERIOR
TABLE OF CONTENTS
page page
DOME LAMP
DESCRIPTION.........................26
OPERATION...........................26
REMOVAL.............................26
INSTALLATION.........................26
DOOR AJAR SWITCH
DESCRIPTION.........................27
OPERATION...........................27GLOVE BOX LAMP/SWITCH
REMOVAL.............................27
INSTALLATION.........................28
READING LAMP
DESCRIPTION.........................28
OPERATION...........................28
REMOVAL.............................28
INSTALLATION.........................29
DOME LAMP
DESCRIPTION
The dome lamp is controlled by the instrument
cluster which provides power at all times, regardless
of the ignition switch position. The ground circuit for
the lamp is switched through the integral dome lamp
switch or through the door ajar switches via the
instrument cluster.
The dome lamp lens and bulb are available for ser-
vice replacement. If either of the lamp switch or bulb
holders is faulty or damaged, the dome lamp assem-
bly must be replaced.
For service of the dome lamp bulb, refer to the
appropriate wiring information.
OPERATION
The dome lamp is activated by the door ajar
switches via the instrument cluster. When all of the
doors are closed, the lamp can be activated by
depressing the lens. When any door is open, depress-
ing the lamp lense to activate the lamp switch will
not turn the lamps off.
The instrument cluster monitors the door ajar
switches. When a door is open the instrument cluster
grounds the low side drivers to turn on the lamp.
Upon closing all doors, the instrument cluster ini-
tiates a 30 second timer. If any of the doors are
opened during the ªtime outº cycle, the instrument
cluster will reset the timer until all doors are closed.
The instrument cluster will faid to off when the doors
are closed and the ignition is turned ON, the time
out expires or the power locks are activated.
REMOVAL
(1) Using a small flat blade, pry the left side (driv-
er's side) of the dome lamp lens downward from
dome lamp.(2) Allow the lens to hang down (Fig. 1), this will
disengage the right side of the lamp (passenger's
side) from the headliner.
(3) Pull the right side of the lamp down and slide
the lamp to the right (Fig. 2).
(4) Separate the lamp from the headliner.
(5) Disengage dome lamp wire connector from body
wire harness.
(6) Separate dome lamp from vehicle.
INSTALLATION
(1) Position dome lamp at headliner.
(2) Connect dome lamp wire connector to body
wire harness.
(3) Position the left side of the lamp in the head-
liner opening and slide lamp to the left (Fig. 1).
Fig. 1 Dome Lamp Lens
1 - HEADLINER
2 - CONNECTOR
3 - DOME LAMP
4 - LENS
5 - BULB
8L - 26 LAMPS/LIGHTING - INTERIORDR

(4) Push the right side of the lamp in the head-
liner opening and push the lamp lens up into the
lamp to secure (Fig. 1).
DOOR AJAR SWITCH
DESCRIPTION
The door ajar switches are integral to the door
latches on each door. The switches close a path to
ground for the Instrument Cluster when a door is
opened.
The door ajar switches cannot be repaired and, if
faulty or damaged, the door latch unit must be
replaced. Refer to the Body section under Doors for
the removal and installation procedure.
OPERATION
The door ajar switches close a path to ground for
the Instrument Cluster when a door is opened. The
passenger front door is connected in a parallel-series
circuit between ground and the Instrument Cluster,
while the driver side front door ajar switch is con-
nected in series between ground and the Instrument
Cluster to provide a unique input. The Instrument
Cluster reads the switch status, then sends the
proper switch status messages to other electronic
modules over the Programmable Communications
Interface (PCI) data bus network. The door ajar
switches can be diagnosed using conventional diag-
nostic tools and methods. Refer to the Body section
under Doors for the Removal and Installation proce-
dures.
GLOVE BOX LAMP/SWITCH
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the glove box from the instrument
panel. (Refer to 23 - BODY/INSTRUMENT PANEL/
GLOVE BOX - REMOVAL) for the procedures.
(3) Reach through the glove box opening and
behind the glove box lamp and switch mounting
bracket to access the instrument panel wire harness
connector on the glove box lamp and switch (Fig. 3).
(4) Disconnect the instrument panel wire harness
connector from the connector receptacle on the back
of the glove box lamp and switch unit.
(5) Reach through the glove box opening and
behind the glove box lamp and switch mounting
bracket to depress the retaining tabs on the top and
bottom of the glove box lamp and switch housing.
(6) While holding the retaining tabs depressed,
push the glove box lamp and switch unit out through
the hole in the mounting bracket on the instrument
panel glove box opening upper reinforcement.
(7) Remove the glove box lamp and switch unit
from the instrument panel.
Fig. 2 Dome Lamp
1 - SLIDE LAMP
Fig. 3 Glove Box Lamp and Switch Remove/Install
1 - WIRE HARNESS CONNECTOR
2 - DASH BOARD
3 - GLOVE BOX SWITCH/LIGHT
DRLAMPS/LIGHTING - INTERIOR 8L - 27
DOME LAMP (Continued)

INSTALLATION
(1) Reach through the glove box opening and
behind the glove box lamp and switch mounting
bracket to feed the instrument panel wire harness
connectors out through the hole in the glove box
lamp and switch housing mounting bracket.
(2) Position the glove box lamp and switch unit to
the instrument panel.
(3) Reconnect the instrument panel wire harness
connector to the connector receptacle on the back of
the glove box lamp and switch unit.
(4) Push the glove box lamp and switch unit into
the hole in the mounting bracket on the instrument
panel glove box opening upper reinforcement.
(5) Install the glove box onto the instrument panel.
(Refer to 23 - BODY/INSTRUMENT PANEL/GLOVE
BOX - INSTALLATION) for the procedures.
(6) Close the glove box.
(7) Reconnect the battery negative cable.
READING LAMP
DESCRIPTION
The overhead console in this vehicle is equipped
with two individual reading and courtesy lamps. The
lamp lenses are the only visible components of these
lamps. Each lamp has its own switch, bulb, reflector
and lens within the overhead console.
The overhead console reading and courtesy lamps
are controlled by the instrument cluster which pro-
vides power at all times, regardless of the ignition
switch position. The ground circuit for the lamps is
switched through the integral reading and courtesy
lamp switches or through the door ajar switches.
Each lamp is designed and aimed to provide illumi-
nation that will be directed only to that side of the
vehicle on which the lamp is located.
The reading and courtesy lamp lenses and bulbs
are available for service replacement. The reading
and courtesy lamp switches, bulb holders and wiring
are only available as part of the overhead console
wire harness. If either of the lamp switches or bulb
holders is faulty or damaged, the entire overhead
console wire harness assembly must be replaced.
For service of the reading and courtesy lamp bulbs,
refer to the appropriate wiring information.
OPERATION
All reading and courtesy lamps located in the over-
head console are activated by the door ajar switches
via the instrument cluster. When all of the doors are
closed, these lamps can be individually activated by
depressing the corresponding lens. When any door is
open, depressing the lamp lenses to activate the lamp
switches will not turn the lamps off.The instrument cluster monitors the door ajar
switches. When a door is open the instrument cluster
grounds the low side drivers to turn on the lamps.
Upon closing all doors, the instrument cluster ini-
tiates a 30 second timer. If any of the doors are
opened during the ªtime outº cycle, the instrument
cluster will reset the timer until all doors are closed.
The instrument cluster will faid to off when the doors
are closed and the ignition is turned ON, the time
out expires or the power locks are activated.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Insert a long, narrow, flat-bladed tool between
the curved (outboard) edge of the reading and cour-
tesy lamp lens and the overhead console housing
(Fig. 4).
(3) Gently pry inward and downward against the
lens until the latch tab in the center of the outboard
edge of the reading and courtesy lamp lens is disen-
gaged from the overhead console housing.
(4) Pull firmly on the lens toward the outboard
side of the vehicle to disengage the two pivot tabs on
the inboard edge of the reading and courtesy lamp
lens are disengaged from the overhead console hous-
ing.
(5) Remove the reading and courtesy lamp lens
from the overhead console housing.
Fig. 4 Overhead Console Reading Lamp Bulb
Removal
1 - LENS
2 - FLAT BLADE
3 - CONSOLE
8L - 28 LAMPS/LIGHTING - INTERIORDR
GLOVE BOX LAMP/SWITCH (Continued)

The compass unit also will compensate for magne-
tism the body of the vehicle may acquire during nor-
mal use. However, avoid placing anything magnetic
directly on the roof of the vehicle. Magnetic mounts
for an antenna, a repair order hat, or a funeral pro-
cession flag can exceed the compensating ability of
the compass unit if placed on the roof panel. Mag-
netic bit drivers used on the fasteners that hold the
overhead console assembly to the roof header can
also affect compass operation. If the vehicle roof
should become magnetized, the demagnetizing and
calibration procedures found in this section may be
required to restore proper compass operation.
TEMPERATURE DISPLAY
All the available overhead consoles on this model
include Temperature information. The temperature
displays the outside ambient temperature in whole
degrees. The temperature display can be toggled
from Fahrenheit to Celsius by selecting the desired
U.S./Metric option from the customer programmable
features. The displayed temperature is not an instant
reading of conditions, but an average temperature. It
may take the temperature display several minutes to
respond to a major temperature change, such as driv-
ing out of a heated garage into winter temperatures.
When the ignition switch is turned to the Off posi-
tion, the last displayed temperature reading stays in
the electronic control modules, (CMTC, EVIC) mem-
ory. When the ignition switch is turned to the On
position again, the electronic module will display the
memory temperature for one minute; then update the
display to the current average temperature reading
within five minutes.The temperature function is supported by an ambi-
ent temperature sensor. This sensor is mounted out-
side the passenger compartment near the front and
center of the vehicle, and is hard wired to the Front
Control Module (FCM). The FCM sends temperature
status messages to the module over the J1850 PCI
data bus circuit. For more information on the ambi-
ent temperature sensor, refer to Ambient Tempera-
ture Sensor later in this section.
Following are general descriptions of the major
components used in the overhead console. Refer to
Wiring Diagrams for complete circuit schematics.
OPERATION
Refer to the vehicle Owner's Manual for specific
operation of each overhead console and its systems.
DIAGNOSIS AND TESTING - OVERHEAD
CONSOLE
If the problem with the overhead console is an
inaccurate or scrambled display, refer toSELF-DI-
AGNOSTIC TESTlater in this text. If the problem
with the overhead console is incorrect Vacuum Fluo-
rescent Display (VFD) dimming levels, use a DRB
IIItscan tool and the proper Diagnostic Procedures
manual to test for the correct dimming message
inputs being received from the Body Control Module
(BCM) or Front Control Module (FCM) over the
J1850 Programmable Communications Interface
(PCI) data bus circuit. If the problem is a no-display
condition, use the following procedure. For complete
circuit diagrams, refer toOverhead Consolein the
Wiring Diagrams section of the service manual.
(1) Remove the overhead console from the head-
liner (Refer to 8 - ELECTRICAL/OVERHEAD CON-
SOLE - REMOVAL).
(2) Check for battery voltage at the overhead con-
sole electrical connector. Refer to Wiring for connec-
tor information. If OK, go to Step 3. If not OK, Check
for battery voltage at the appropriate B(+) fuse in the
integrated power module, repair the open fused B(+)
circuit as required.
(3) Turn the ignition switch to the On position.
Check the fused ignition switch output circuit(s) at
the overhead console electrical connector. If OK, go to
Step 4. If not OK, repair the open or shorted circuit
as required.
(4) Turn the ignition switch to the Off position.
Disconnect and isolate the battery negative cable.
Check for continuity between the ground circuit cav-
ity of the overhead console electrical connector and a
good ground. There should be continuity. If OK, refer
toSELF-DIAGNOSTIC TESTbelow for further
diagnosis of the electronics module and the J1850
PCI data bus circuit. If not OK, repair the open
ground circuit as required.
Fig. 1 DR OVERHEAD CONSOLE ± EVIC
8M - 2 MESSAGE SYSTEMSDR
OVERHEAD CONSOLE (Continued)

POWER LOCK SWITCH
DIAGNOSIS AND TESTING - POWER LOCK
SWITCH
The Light-Emitting Diode (LED) illumination lamp
of the power lock switch receives battery current
through a fuse in the Integrated Power Module (IPM)
on a fused ignition switch output (run) circuit. The
power lock switch on the driver side front door trim
panel is integral to the driver door module. (Refer to
8 - ELECTRICAL/POWER LOCKS/DOOR MODULE
- DIAGNOSIS AND TESTING). If the power lock
switch operates, but the LED is inoperative, check
for battery current at the switch with the ignition
switch in the On position. If OK, replace the faulty
switch. Refer to the appropriate wiring information.
(1) Disconnect and isolate the battery negative
cable. Remove the power lock switch from the door
trim panel. Disconnect the door wire harness connec-
tor for the power lock switch from the switch connec-
tor receptacle.
(2) Test the power lock switch resistance. See the
Power Lock Switch Test chart to determine if the
resistance is correct for the switch in each switch
position (Fig. 1). If not OK, replace the faulty power
lock switch as required.
POWER LOCK SWITCH TEST TABLE
SWITCH POSITION RESISTANCE BETWEEN
PINS1&5
NEUTRAL 10 KILOHMS  1%
LOCK 820 OHMS  5%
UNLOCK 330 OHMS  5%
REMOVAL
The power lock switch on the driver side front door
trim panel is integral to the driver door module.
(Refer to 8 - ELECTRICAL/POWER LOCKS/DOOR
MODULE - REMOVAL).
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the door trim panel (Refer to 23 -
BODY/DOOR - FRONT/TRIM PANEL - REMOVAL).
(3) Remove the switch from the trim panel bezel.
INSTALLATION
(1) Insert switch to trim panel bezel.
(2) Install door trim panel (Refer to 23 - BODY/
DOOR - FRONT/TRIM PANEL - INSTALLATION).
(3) Connect battery negative cable.
DOOR LOCK MOTOR
DESCRIPTION
The lock mechanisms are actuated by a reversible
electric motor mounted within each door. The power
lock motors are integral to the door latch units.
The power lock motors cannot be adjusted or
repaired and, if faulty or damaged, the door latch
unit must be replaced.
OPERATION
The door lock motors are controlled by the instru-
ment cluster. A positive and negative battery connec-
tion to the two motor terminals will cause the motor
to move in one direction. Reversing the current will
cause the motor to move in the opposite direction.
DIAGNOSIS AND TESTING - DOOR LOCK
MOTOR
The most reliable, efficient, and accurate means to
diagnose the power lock system requires the use of a
DRBIIItscan tool and the proper Diagnostic Proce-
dures manual.
Refer to the appropriate wiring information.
Fig. 1 Power Lock Switch Connector Receptacle
8N - 4 POWER LOCKSDR

DRIVER DOOR MODULE SWITCH TESTS
LEFT FRONT DOWN PINS9&12
RIGHT FRONT UP PINS3&9
RIGHT FRONT DOWN PINS6&9
LEFT REAR UP PINS4&9
LEFT REAR DOWN PINS9&10
RIGHT REAR UP PINS2&9
RIGHT REAR DOWN PINS1&9
POWER WINDOW LOCKOUT SWITCH
SWITCH POSITION CONTINUITY BETWEEN
OFF (SWITCH BUTTON
RAISED - NOT
DEPRESSED)PIN 9 OF CONNECTOR
C-1&PIN8OF
CONNECTOR C-2
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the door trim panel (Refer to 23 -
BODY/DOOR - FRONT/TRIM PANEL - REMOVAL).
(3) Remove the driver door module from the trim
panel bezel.
INSTALLATION
(1) Install driver door module to trim panel bezel.
(2) Install door trim panel (Refer to 23 - BODY/
DOOR - FRONT/TRIM PANEL - INSTALLATION).
(3) Connect battery negative cable.
REMOTE KEYLESS ENTRY
MODULE
DESCRIPTION
When an RKE lock message is sent to the instru-
ment cluster, the instrument cluster actuates the
door locks, the interior lighting is turned off, the
horn chirps (if this feature is enabled), the park
lamps flash (if this feature is enabled) and, if the
vehicle is so equipped, the Vehicle Theft Security
System (VTSS) is armed. When an RKE unlock mes-
sage is sent to the instrument cluster, the instrument
cluster actuates the driver side front door (or all
doors if this feature is enabled) unlock, the interior
lighting is turned on and, if the vehicle is so
equipped, the VTSS is disarmed.
When an RKE panic message is sent to the instru-
ment cluster, the instrument cluster actuates the
driver side front door (or all doors if this feature is
enabled) unlock, the interior lighting is turned on
and, if the vehicle is so equipped, the VTSS is dis-
armed. The panic message will also cause the exte-
rior lamps (including the headlights) to flash, andthe horn to sound for about three minutes, or until a
second panic message is sent to the instrument clus-
ter. A vehicle speed of about 25.7 kilometers-per-hour
(15 miles-per-hour) will also cancel the panic event.
Refer to the owner's manual for more information
on the features, use and operation of the RKE sys-
tem.
OPERATION
Whenever the vehicle battery power is interrupted,
the Remote Keyless Module (RKE) Module will retain
all vehicle access codes in its memory. When replac-
ing or adding a key fob transmitter (maximum of 4) a
DRB IIItscan tool is required to program the RKE
Module to accept the new Vehicle Access Code if a
customer owned transmitter is not available.
If a functioning transmitter is available, (Refer to 8
- ELECTRICAL/POWER LOCKS/KEYLESS ENTRY
TRANSMITTER - STANDARD PROCEDURE)
DIAGNOSIS AND TESTING - REMOTE KEYLESS
ENTRY MODULE
The most reliable, efficient, and accurate means to
diagnose the power lock system requires the use of a
DRBIIItscan tool and the proper Diagnostic Proce-
dures manual.
Refer to the appropriate wiring information.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the instrument cluster (Refer to 8 -
ELECTRICAL/INSTRUMENT CLUSTER -
REMOVAL).
(3) Remove remote keyless entry module from
instrument cluster (Fig. 4).
Fig. 4 REMOTE KEYLESS ENTRY MODULE
1 - INSTRUMENT CLUSTER
2 - REMOTE KEYLESS ENTRY MODULE
DRPOWER LOCKS 8N - 7
DRIVER DOOR MODULE (Continued)