1998 DODGE RAM 1500 Engine fuse box

(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 backup lamp bulb into the backup
lamp socket by pushing inward and rotating it clock-
wise.
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.
BACKUP LAMP SWITCH
DESCRIPTION
Vehicles equipped with a manual transmission
have a normally open, spring-loaded plunger typeback-up lamp switch (Fig. 2). The backup lamp
switch is located in a threaded hole on the side of the
manual transmission housing. The backup lamp
switch has a threaded body and a hex formation near
the plunger end of the switch, and an integral con-
nector at the opposite end of the switch. When
installed, only the connector and the hex formation
are visible on the outside of the transmission hous-
ing. Vehicles with an optional electronic automatic
transmission have a Transmission Range Sensor
(TRS) that is used to perform several functions,
including that of the backup lamp switch. The TRS is
described in further detail elsewhere in this service
information. The backup lamp switch cannot be
adjusted or repaired and, if faulty or damaged, the
entire switch unit must be replaced.
OPERATION
The backup lamp switch controls the flow of bat-
tery voltage to the backup lamp bulbs through an
output on the back-up lamp feed circuit. The switch
plunger is mechanically actuated by the gearshift
mechanism within the transmission, which will
depress the switch plunger and close the switch con-
tacts whenever the reverse gear has been selected.
The switch receives battery voltage through a fuse in
the Integrated Power Module (IPM) on a fused igni-
tion switch output (run) circuit whenever the ignition
switch is in the On position. A take out of the engine
wire harness connects the backup lamp switch to the
vehicle electrical system. The backup lamp switch
and circuits can be tested using conventional diag-
nostic tools and methods.
DIAGNOSIS AND TESTING - BACKUP LAMP
SWITCH
(1) Disconnect and isolate the battery negative
cable.
(2) Raise and support the vehicle.
(3) Locate and disconnect the engine wire harness
connector for the backup lamp switch.
(4) Check for continuity between the two terminal
pins in the backup lamp switch connector.
(a) With the gear selector lever in the Reverse
position, there should be continuity.
(b) With the gear selector lever in any position
other than Reverse, there should be no continuity.
Fig. 2 Backup Lamp Switch - Typical
1 - MANUAL TRANSMISSION
2 - BACKUP LAMP SWITCH
3 - ENGINE WIRE HARNESS
8L - 8 LAMPS/LIGHTING - EXTERIORDR
BACKUP LAMP (Continued)

8W-02 COMPONENT INDEX
Component Page
A/C Compressor Clutch................. 8W-42
A/C Compressor Clutch Relay............ 8W-42
A/C Pressure Transducer................ 8W-42
A/C-Heater Control.................... 8W-42
Accelerator Pedal Position Sensor......... 8W-30
Adjustable Pedal Motor................. 8W-30
Adjustable Pedal Relay................. 8W-30
Adjustable Pedal Switch................ 8W-30
Airbag Control Module................. 8W-43
Airbag-Squibs........................ 8W-43
Airbag-Curtains....................... 8W-43
Airbag-Passenger On/Off Switch.......... 8W-43
Ambient Temperature Sensor............ 8W-49
Amplifier Audio....................... 8W-47
Ashtray Lamp........................ 8W-44
Auto Shut Down Relay................. 8W-30
Automatic Day/Night Mirror.......... 8W-49, 55
Auxiliary Battery..................... 8W-20
Backup Lamp Switch.................. 8W-51
Battery............................. 8W-20
Battery Temperature Sensor............. 8W-30
Blend Door Actuators.................. 8W-42
Blower Motor......................... 8W-42
Blower Motor Resistor Block............. 8W-42
Brake Fluid Level Switch............ 8W-34, 35
Brake Lamp Switch.................... 8W-33
Brake Transmission Shift Interlock
Solenoid........................... 8W-40
Camshaft Position Sensor............... 8W-30
Capacitor............................ 8W-30
Center High Mounted Stop Lamp-
Aftermarket........................ 8W-51
Center High Mounted Stop Lamp/Cargo
Lamp.......................... 8W-44, 51
Cigar Lighter Outlet................... 8W-41
Circuit Breaker....................... 8W-10
Clearance Lamps...................... 8W-50
Clockspring................. 8W-33, 41, 43, 47
Clutch Interlock Brake Switch........... 8W-21
Coil On Plugs........................ 8W-30
Compass/Mini-Trip Computer............ 8W-49
Condenser Fan....................... 8W-42
Condenser Fan Relay.................. 8W-42
Controller Antilock Brake............ 8W-34, 35
Crankshaft Position Sensor.............. 8W-30
Cylinder Lock Switch-Driver............. 8W-61
Data Link Connector................... 8W-18
Data Link Connector-Engine............. 8W-18
Dome Lamp....................... 8W-44, 49
Door Ajar Switches.................... 8W-40
Door Lock Motor/Ajar Switches........ 8W-40, 61
Door Lock Switch-Passenger............. 8W-61Component Page
Door Module................... 8W-60, 61, 62
EGR Solenoid........................ 8W-30
Electric Backlight..................... 8W-48
Electric Brake Provision................ 8W-54
Electronic Throttle Control Module........ 8W-30
Engine Control Module................. 8W-30
Engine Coolant Temperature Sensor....... 8W-30
Engine Oil Pressure Switch.............. 8W-30
EVAP/Purge Solenoid.................. 8W-30
Evaporator Temperature Sensor.......... 8W-42
Fender Lamps........................ 8W-51
Fog Lamp Relay...................... 8W-50
Fog Lamps.......................... 8W-50
Front Control Module.................. 8W-10
Fuel Control Actuator.................. 8W-30
Fuel Heater.......................... 8W-30
Fuel Heater Relay..................... 8W-30
Fuel Injector Packs.................... 8W-30
Fuel Injectors........................ 8W-30
Fuel Pump Module.................... 8W-30
Fuel Pump Motor..................... 8W-30
Fuel Pump Relay...................... 8W-30
Fuses............................ 8W-10, 33
Fusible Link......................... 8W-10
Generator........................... 8W-20
Glove Box Lamp And Switch............. 8W-44
Grounds............................ 8W-15
Hands Free Module.................... 8W-55
Headlamp Switch.................. 8W-40, 50
Headlamps.......................... 8W-50
Heated Mirror Relay................... 8W-62
Heated Seat Cushions.................. 8W-63
Horn Relay.......................... 8W-41
Horn Switch......................... 8W-41
Horn-High Note....................... 8W-41
Horn-Low Note....................... 8W-41
Idle Air Control Motor.................. 8W-30
Ignition Switch....................... 8W-10
Inlet Air Temperature Sensor............ 8W-30
Input Speed Sensor.................... 8W-31
Instrument Cluster.................... 8W-40
Intake Air Heater Relays............... 8W-30
Intake Air Temperature Sensor........... 8W-30
Intake Air Temperature/Manifold Absolute
Pressure Sensor..................... 8W-30
Integrated Power Module............... 8W-10
Knock Sensosr........................ 8W-30
License Lamps....................... 8W-51
Lift Pump Motor...................... 8W-30
Line Pressure Sensor................ 8W-30, 31
Lumbar Motors....................... 8W-63
Lumbar Switch....................... 8W-63
DR8W-02 COMPONENT INDEX 8W - 02 - 1

requires the use of a DRB IIItscan tool and the
proper Body Diagnostic Procedures manual.
Before any testing of the front control module is
attempted, the battery should be fully charged and
all wire harness and ground connections inspected
around the affected areas on the vehicle.
REMOVAL
(1) Disconnect the positive and negative battery
cables from the battery.
(2) Partially remove the integrated power module
from the engine compartment (Refer to 8 - ELECTRI-
CAL/POWER DISTRIBUTION/INTEGRATED
POWER MODULE - REMOVAL).
(3) Remove the front control module retaining
screws.
(4) Using both hands, pull the front control module
straightfrom the integrated power module assembly
to disconnect the 49-way electrical connector and
remove the front control module from the vehicle.
INSTALLATION
(1) Install the front control module on the inte-
grated power module assembly by pushing the
49-way electrical connector straight in.
(2) Install the front control module retaining
screws. Torque the screws to 7 in. lbs.
(3) Install the integrated power module (Refer to 8
- ELECTRICAL/POWER DISTRIBUTION/INTE-
GRATED POWER MODULE - INSTALLATION).
(4) Connect the positive and negative battery
cables.
IOD FUSE
DESCRIPTION
All vehicles are equipped with an Ignition-Off
Draw (IOD) fuse that is disconnected within the Inte-
grated Power Module when the vehicle is shipped
from the factory. Dealer personnel are to reconnect
the IOD fuse in the Integrated Power Module as part
of the preparation procedures performed just prior to
new vehicle delivery.
A laser printed fuse layout map is integral to the
Integrated Power Module cover to ensure proper fuse
identification. The IOD fuse is a 20 ampere mini
blade-type fuse, located in fuse cavity # 51 (Fig. 6).
The fuse is secured within a black molded plastic
fuse holder and puller unit that serves both as a tool
for disconnecting and reconnecting the fuse in its
Integrated Power Module cavity, and as a fuse holder
that conveniently stores the fuse in the same Inte-
grated Power Module cavity after it has been discon-
nected.
CIRCUITS INCLUDED WITH IOD FUSE
²Cluster (CCN)
²Diagnostic Connector
²Map Lamps
²Glove Box Lamp
²Courtesy Lamps
²Radio
²Underhood Lamp
OPERATION
The term ignition-off draw identifies a normal con-
dition where power is being drained from the battery
with the ignition switch in the Off position. The IOD
fuse feeds the memory and sleep mode functions for
some of the electronic modules in the vehicle as well
as various other accessories that require battery cur-
rent when the ignition switch is in the Off position.
The only reason the IOD fuse is disconnected is to
reduce the normal IOD of the vehicle electrical sys-
tem during new vehicle transportation and pre-deliv-
ery storage to reduce battery depletion, while still
allowing vehicle operation so that the vehicle can be
loaded, unloaded and moved as needed by both vehi-
cle transportation company and dealer personnel.
The IOD fuse is disconnected from Integrated
Power Module fuse cavity # 51 when the vehicle is
shipped from the assembly plant. Dealer personnel
must reconnect the IOD fuse when the vehicle is
being prepared for delivery in order to restore full
electrical system operation. Once the vehicle is pre-
pared for delivery, the IOD function of this fuse
Fig. 6 IOD FUSE LOCATION
1 - IOD FUSE
8W - 97 - 6 8W-97 POWER DISTRIBUTIONDR
FRONT CONTROL MODULE (Continued)