1998 DODGE RAM 1500 tv cable

PARK LAMP RELAY
DESCRIPTION
The park lamp relay is located in the Power Dis-
tribution Center (PDC) of the vehicle. The park lamp
relay is a conventional International Standards
Organization (ISO) micro relay (Fig. 17). Relays con-
forming to the ISO specifications have common phys-
ical dimensions, current capacities, terminal
patterns, and terminal functions.
The park lamp relay cannot be adjusted or
repaired and, if faulty or damaged, the unit must be
replaced.
OPERATION
The park lamp 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 park lamps. 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 park lamp relay terminals are connected to
the vehicle electrical system through a connector in
the Junction Block (JB). The inputs and outputs of
the headlamp low beam relay include:
²Common Feed Terminal- The common feed
terminal (30) is connected to the park lamps through
the park lamp relay output circuit and provides
ground to the park lamps when the relay is de-ener-
gized, and battery current to the park lamps when-
ever the relay is energized.
²Coil Ground Terminal- The coil ground termi-
nal (85) is connected to a control output of the Front
Control Module (FCM) through a park lamp relay
control circuit. The FCM controls park lamp 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 PDC through a fused B(+) circuit.
²Normally Open Terminal- The normally open
terminal (87) receives battery current at all times
from a fuse in the Power Distribution Center (PDC)
through a fused B(+) circuit.
²Normally Closed Terminal- The normally
closed terminal (87A) is connected to ground at all
times.
The park lamp relay can be diagnosed using con-
ventional diagnostic tools and methods.
DIAGNOSIS AND TESTING - PARK LAMP
RELAY
The park lamp relay (Fig. 18) is located in the
Power Distribution Center (PDC). Refer to the appro-
priate wiring information.
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE SUPPLEMENTAL RESTRAINT
SYSTEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, DRIVER AIRBAG,
PASSENGER AIRBAG, SEAT BELT TENSIONER,
FRONT IMPACT SENSORS, SIDE CURTAIN AIRBAG,
OR INSTRUMENT PANEL COMPONENT DIAGNOSIS
OR SERVICE. DISCONNECT AND ISOLATE THE
BATTERY NEGATIVE (GROUND) CABLE, THEN
WAIT TWO MINUTES FOR THE SYSTEM CAPACI-
TOR TO DISCHARGE BEFORE PERFORMING FUR-
THER DIAGNOSIS OR SERVICE. THIS IS THE ONLY
SURE WAY TO DISABLE THE SUPPLEMENTAL
RESTRAINT SYSTEM. FAILURE TO TAKE THE
PROPER PRECAUTIONS COULD RESULT IN ACCI-
DENTAL AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
(1) Remove the park lamp relay from the PDC.
(2) A relay in the de-energized position should
have continuity between terminals 87A and 30, and
Fig. 17 ISO Micro Relay
30 - COMMON FEED
85 - COIL GROUND
86 - COIL BATTERY
87 - NORMALLY OPEN
87A - NORMALLY CLOSED
8L - 20 LAMPS/LIGHTING - EXTERIORDR

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
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE SUPPLEMENTAL RESTRAINT
SYSTEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, DRIVER AIRBAG,
PASSENGER AIRBAG, SEAT BELT TENSIONER,
FRONT IMPACT SENSORS, SIDE CURTAIN AIRBAG,
OR INSTRUMENT PANEL COMPONENT DIAGNOSIS
OR SERVICE. DISCONNECT AND ISOLATE THE
BATTERY NEGATIVE (GROUND) CABLE, THEN
WAIT TWO MINUTES FOR THE SYSTEM CAPACI-
TOR TO DISCHARGE BEFORE PERFORMING FUR-
THER DIAGNOSIS OR SERVICE. THIS IS THE ONLY
SURE WAY TO DISABLE THE SUPPLEMENTAL
RESTRAINT SYSTEM. FAILURE TO TAKE THE
PROPER PRECAUTIONS COULD RESULT IN ACCI-
DENTAL AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
(1) Disconnect and isolate the battery negative
cable.(2) Remove the Power Distribution Center (PDC)
cover.
(3) Remove the park lamp relay by grasping it
firmly and pulling it straight out from the receptacle
in the PDC.
INSTALLATION
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE SUPPLEMENTAL RESTRAINT
SYSTEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, DRIVER AIRBAG,
PASSENGER AIRBAG, SEAT BELT TENSIONER,
FRONT IMPACT SENSORS, SIDE CURTAIN AIRBAG,
OR INSTRUMENT PANEL COMPONENT DIAGNOSIS
OR SERVICE. DISCONNECT AND ISOLATE THE
BATTERY NEGATIVE (GROUND) CABLE, THEN
WAIT TWO MINUTES FOR THE SYSTEM CAPACI-
TOR TO DISCHARGE BEFORE PERFORMING FUR-
THER DIAGNOSIS OR SERVICE. THIS IS THE ONLY
SURE WAY TO DISABLE THE SUPPLEMENTAL
RESTRAINT SYSTEM. FAILURE TO TAKE THE
PROPER PRECAUTIONS COULD RESULT IN ACCI-
DENTAL AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
(1) Position the park lamp relay to the proper
receptacle in the Power Distribution Center (PDC).
(2) Align the park lamp relay terminals with the
terminal cavities in the PDC.
(3) Press firmly and evenly on the top of the park
lamp relay until the terminals are fully seated in the
PDC.
(4) Install the PDC cover.
(5) Reconnect the battery negative cable.
PARK/TURN SIGNAL LAMP
REMOVAL
(1) Disconnect and isolate the negative battery
cable.
(2) Remove the headlamp unit.(Refer to 8 - ELEC-
TRICAL/LAMPS/LIGHTING - EXTERIOR/HEAD-
LAMP UNIT - REMOVAL).
(3) Remove the bulb socket from the headlamp
unit.
(4) Release the front park/turn signal bulb locking
tabs and remove the bulb from the socket (Fig. 19).
INSTALLATION
(1) Install the front park/turn signal bulb into the
bulb socket.
(2) Install the bulb socket into the headlamp unit.
(3) Install the headlamp unit (Refer to 8 - ELEC-
TRICAL/LAMPS/LIGHTING - EXTERIOR/HEAD-
LAMP UNIT - INSTALLATION).
Fig. 18 ISO Micro Relay
30 - COMMON FEED
85 - COIL GROUND
86 - COIL BATTERY
87 - NORMALLY OPEN
87A - NORMALLY CLOSED
DRLAMPS/LIGHTING - EXTERIOR 8L - 21
PARK LAMP RELAY (Continued)

(4) Reconnect the negative battery cable.
TAIL 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 tail lamp 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. 20).
(3) Separate the tail lamp lens from the tail lamp
housing.
(4) Push the tail lamp bulb inward and rotate it
counter-clockwise.
(5) Remove the tail lamp bulb from the tail lamp
socket.
INSTALLATION
INSTALLATION - WITH CARGO BOX
(1) Install the tail lamp 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 tail lamp 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.
TAIL LAMP UNIT
REMOVAL
REMOVAL - WITH CARGO BOX
(1) Disconnect and isolate the negative battery
cable.
(2) Lower the tailgate.
(3) Remove the two screws that secure the tail
lamp unit to the cargo box.
(4) Remove the tail lamp unit from the cargo box.
(5) Disconnect the body wire harness connector
from the lamp back plate connector (Fig. 21).
Fig. 19 Park Turn Signal Bulb
1 - BULB SOCKET
2 - BULB
Fig. 20 Tail Lamp Lens
8L - 22 LAMPS/LIGHTING - EXTERIORDR
PARK/TURN SIGNAL LAMP (Continued)

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

UNDERHOOD LAMP
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Insert a small flat blade in the access slot
between the lamp base and lamp lens.
(3) Pry the lamp lens upward and remove the
lamp lens (Fig. 25).
(4) Depress the bulb terminal inward (Fig. 26) to
release the bulb.
INSTALLATION
(1) Engage the replacement bulb wire loop to the
terminal closest to the lamp base wire connector (Fig.
26).
(2) Depress the opposite terminal inward and
engage the remaining bulb wire loop.
(3) Position the lamp lens on the lamp base and
press into place (Fig. 25).
(4) Connect the battery negative cable.
UNDERHOOD LAMP UNIT
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Disconnect the wire harness connector from the
lamp.
(3) Remove lamp lens.
(4) Remove bulb.
(5) Remove screw attaching underhood lamp to the
inner hood panel (Fig. 27).
(6) Separate underhood lamp from vehicle.
INSTALLATION
(1) Install bulb.
(2) Install lamp lens.
(3) Position the underhood lamp on the hood inner
panel.
(4) Install the attaching screw through the lamp
and into the hood panel (Fig. 27). Tighten the screw
securely.
(5) Fold lamp housing over and firmly press onto
base to snap into place.
(6) Connect the wire harness connector to the
lamp.
(7) Connect the battery negative cable.
Fig. 25 Underhood Lamp Lens
1 - LAMP
2 - LAMP LENS
Fig. 26 Underhood Lamp Bulb
1 - BULB
2 - DEPRESS TERMINAL INWARD
3 - BULB WIRE LOOP
4 - LAMP BASE
Fig. 27 Underhood Lamp
1 - UNDER HOOD LAMP
2 - HOOD
3 - CONNECTOR
DRLAMPS/LIGHTING - EXTERIOR 8L - 25

(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)