RAM 1500 Truck 2WD V6-3.9L VIN X (1999)
Power Distribution Center: Description and Operation
Fig 1 Power Distribution Center
POWER DISTRIBUTION CENTER DESCRIPTION
All of the electrical current distributed throughout this vehicle is directed through the standard equipment Power Distribution Center (PDC).
The molded plastic PDC housing is located in the left front corner of the engine compartment, just behind the battery. The PDC housing has a
molded plastic cover that includes two integral latches, one on each side. The PDC cover is easily removed for service access and has a convenient
adhesive-backed fuse and relay layout label affixed to the inside surface of the cover to ensure proper component identification.
The PDC housing is secured in the engine compartment on the outboard side with two screws to the left front inner fender shield, and with a screw
on the inboard side to the left front inner wheel house.
The PDC cover is unlatched and removed to access the battery/generator cable input and output connection studs. The PDC is integral to the
headlamp and dash wire harness, which exits from the inboard end of the PDC housing.
All of the current from the battery/generator cable connections enters the PDC through a 140 ampere generator cartridge fuse that is secured with
screws just inside the inboard end of the PDC housing.
The PDC houses up to twelve maxi-fuse cartridges, which replace all in-line fusible links. The PDC also houses up to thirteen blade-type fuses
(two standard-type and eleven mini-type), up to seventeen International Standards Organization (ISO) relays (five standard-type and twelve
micro-type), two joint connectors (one eighteen-way and one twenty-eight-way), a forty-three-way engine wire harness in-line connector and a fuse
puller. Internal connection of all of the PDC circuits is accomplished by an intricate combination of hard wiring and bus bars.
The cartridge fuses, blade-type fuses and relays are available for service replacement. The PDC unit cannot be repaired and is only serviced as a
unit with the headlamp and dash wire harness. If the internal circuits or the PDC housing are faulty or damaged, the headlamp and dash wire
harness unit must be replaced.
GENERATOR CARTRIDGE FUSE DESCRIPTION
A 140 ampere generator cartridge fuse is secured with two screws to the input and output bus bars within the Power Distribution Center. This
cartridge fuse helps to protect the vehicle electrical system from damage that could be caused by overcharging and/or excessive electrical system
current due to a faulty generator or faulty charging system circuits.
If a generator cartridge fuse fails, be certain to inspect and test the vehicle charging system before replacing the cartridge fuse and returning the
vehicle to service. Refer to Charging System Testing for the proper procedures.
The generator cartridge fuse is available for service replacement. This cartridge fuse cannot be repaired and, if faulty or damaged, must be
replaced.
