DODGE RAM 2001 Service Repair Manual

(1) Turn the ignition switch to the Off position.
(2) To install the IOD fuse, use a thumb to press
the IOD fuse holder unit in fuse cavity 12 firmly into
the JB.
(3) Install the fuse access panel by snapping it
onto the left outboard end of the instrument panel.
JUNCTION BLOCK
DESCRIPTION
An electrical Junction Block (JB) is concealed
behind the left outboard end of the instrument panel
cover (Fig. 5). The JB combines the functions previ-
ously provided by a separate fuseblock module and
relay center, serves to simplify and centralize numer-
ous electrical components, and to distribute electrical
current to many of the accessory systems in the vehi-
cle. It also eliminates the need for numerous splice
connections and serves in place of a bulkhead connec-
tor between many of the engine compartment, instru-
ment panel, and body wire harnesses. The JB houses
up to nineteen blade-type fuses (two standard-type
and seventeen mini-type), up to two blade-type auto-
matic resetting circuit breakers, the electronic combi-
nation turn signal and hazard warning flasher, and
one International Standards Organization (ISO)
micro-relay.The molded plastic JB housing has integral mount-
ing brackets that are secured with two screws to the
left instrument panel end bracket. The left end of the
instrument panel cover has a snap-fit fuse access
panel that can be removed for service of the JB. A
fuse puller and spare fuse holders are located on the
back of the fuse access cover, as well as an adhesive-
backed fuse layout map to ensure proper fuse identi-
fication.
The JB unit cannot be repaired and is only ser-
viced as an assembly. If any internal circuit or the JB
housing is faulty or damaged, the entire JB unit
must be replaced.
OPERATION
All of the circuits entering and leaving the JB do
so through up to nine wire harness connectors, which
are connected to the JB through integral connector
receptacles molded into the JB housing. Internal con-
nection of all of the JB circuits is accomplished by an
intricate combination of hard wiring and bus bars.
Refer toJunction Blockin the index of this service
manual for the location of complete JB circuit dia-
grams.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
Fig. 4 Ignition-Off Draw Fuse
1 - JUNCTION BLOCK
2 - IGNITION-OFF DRAW FUSE AND HOLDER
3 - LEFT INSTRUMENT PANEL END BRACKET
Fig. 5 Junction Block Location
1 - JUNCTION BLOCK
2 - FUSE ACCESS PANEL
8W - 97 - 6 8W-97 POWER DISTRIBUTIONBR/BE
IOD FUSE (Continued)

(2) Roll down the instrument panel from the dash
panel, but do not remove it from the vehicle. Refer to
Instrument Panel Assemblyin the index of this
service manual for the instrument panel assembly
removal procedures.
(3) Reach through the outboard side of the instru-
ment panel steering column opening to access and
disconnect all of the wire harness connectors from
the Junction Block (JB) connector receptacles (Fig.
6).
(4) Reach through the outboard side of the instru-
ment panel steering column opening to access and
remove the two screws that secure the JB to the left
instrument panel end bracket.
(5) Reach through the outboard side of the instru-
ment panel steering column opening to remove the
JB from the left instrument panel end bracket.
INSTALLATION
NOTE: If the Junction Block (JB) is being replaced
with a new unit, be certain to transfer each of the
fuses, circuit breakers and relays from the faulty JB
to the proper cavities of the replacement JB. Refer
to Junction Block in the index of this service man-
ual for the location of complete circuit diagrams
and cavity assignments for the JB.(1) Reach through the outboard side of the instru-
ment panel steering column opening to position the
JB onto the left instrument panel end bracket.
(2) Reach through the outboard side of the instru-
ment panel steering column opening to install and
tighten the two screws that secure the JB to the left
instrument panel end bracket. Tighten the screws to
2.85 N´m (25 in. lbs.).
(3) Reach through the outboard side of the instru-
ment panel steering column opening to access and
reconnect all of the wire harness connectors to the
JB connector receptacles.
(4) Install the instrument panel onto the dash
panel. Refer toInstrument Panel Assemblyin the
index of this service manual for the location of the
instrument panel assembly installation procedures.
(5) Reconnect the battery negative cable.
POWER DISTRIBUTION
CENTER
DESCRIPTION
All of the electrical current distributed throughout
this vehicle is directed through the standard equip-
ment Power Distribution Center (PDC) (Fig. 7). The
molded plastic PDC housing is located in the left
front corner of the engine compartment, just behind
the battery. The PDC houses the generator cartridge
fuse and up to twelve maxi-type cartridge fuses,
Fig. 6 Junction Block Remove/Install
1 - END BRACKET
2 - JUNCTION BLOCK
3 - SCREWS
Fig. 7 Power Distribution Center Location
1 - POWER DISTRIBUTION CENTER
BR/BE8W-97 POWER DISTRIBUTION 8W - 97 - 7
JUNCTION BLOCK (Continued)

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 Interna-
tional Standards Organization (ISO) relays (five
standard-type and twelve micro-type), two joint con-
nectors (one eighteen-way and one twenty-eight-way),
a forty-three-way engine wire harness in-line connec-
tor and a fuse puller.
The PDC housing is secured in the engine compart-
ment 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 housing has a molded plastic cover that
includes two integral latches, one on each side. The
PDC cover is easily opened and removed for service
access and has a convenient adhesive-backed fuse
and relay layout map affixed to the inside surface of
the cover to ensure proper component identification.
The PDC unit cannot be repaired and is only ser-
viced 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.
OPERATION
All of the current from the battery and the gener-
ator output enters the PDC through two cables with
eyelets that are secured with nuts to the two B(+)
terminal studs located just inside the inboard end of
the PDC housing. The PDC cover is unlatched and
removed to access the battery and generator output
connection B(+) terminal studs, the fuses, the relays,
the joint connectors and the engine wire harness in-
line connector. Internal connection of all of the PDC
circuits is accomplished by an intricate combination
of hard wiring and bus bars. Refer toPower Distri-
butionin the index of this service manual for the
location of complete PDC circuit diagrams.
REMOVAL
The Power Distribution Center (PDC) is serviced
as a unit with the headlamp and dash wire harness.
If any internal circuit of the PDC or the PDC hous-
ing is faulty or damaged, the entire PDC and head-
lamp and dash wire harness unit must be replaced.
(1) Disconnect and isolate the battery negative
cable.
(2) Disconnect each of the headlamp and dash wire
harness connectors. Refer toConnector Locations
in the index of this service manual for the location of
more information on the headlamp and dash wire
harness connector locations.
(3) Remove all of the fasteners that secure each of
the headlamp and dash wire harness ground eyelets
to the vehicle body and chassis components. Refer to
Connector Locationsin the index of this servicemanual for the location of more information on the
ground eyelet locations.
(4) Disengage each of the retainers that secure the
headlamp and dash wire harness to the vehicle body
and chassis components. Refer toConnector Loca-
tionsin the index of this service manual for the loca-
tion of more information on the headlamp and dash
wire harness retainer locations.
(5) Unlatch and remove the cover from the PDC.
(6) Remove the screw that secures the engine wire
harness in-line connector to the PDC and disconnect
the connector (Fig. 8).
(7) Remove the nut that secures the eyelet of the
battery negative cable generator output take out to
the rearward B(+) terminal stud in the PDC and
remove the eyelet from the stud (Fig. 9).
(8) Remove the nut that secures the eyelet of the
battery positive cable PDC take out to the forward
B(+) terminal stud in the PDC and remove the eyelet
from the stud.
(9) Remove the screw that secures the PDC hous-
ing to the left front fender wheel housing (Fig. 10).
(10) Remove the two screws that secure the PDC
housing to the left front fender inner shield.
(11) Remove the PDC and the headlamp and dash
wire harness from the engine compartment as a unit.
INSTALLATION
The Power Distribution Center (PDC) is serviced
as a unit with the headlamp and dash wire harness.
If any internal circuit of the PDC or the PDC hous-
ing is faulty or damaged, the entire PDC and head-
lamp and dash wire harness unit must be replaced.
Fig. 8 Engine Wire Harness In-Line Connector
1 - LEFT FENDER
2 - POWER DISTRIBUTION CENTER
3 - ENGINE WIRE HARNESS IN-LINE CONNECTOR
4 - SCREW
8W - 97 - 8 8W-97 POWER DISTRIBUTIONBR/BE
POWER DISTRIBUTION CENTER (Continued)

NOTE: If the PDC is being replaced with a new unit,
be certain to transfer each of the blade-type fuses,
cartridge fuses and relays from the faulty PDC to
the proper cavities of the replacement PDC. Refer
to Power Distribution in the index of this service
manual for the location of complete PDC circuit dia-
grams and cavity assignments.(1) Position the PDC and the headlamp and dash
wire harness unit in the engine compartment.
(2) Install and tighten the two screws that secure
the PDC housing to the left front fender inner shield.
Tighten the screws to 8.4 N´m (75 in. lbs.).
(3) Install and tighten the screw that secures the
PDC housing to the left front fender wheel housing.
Tighten the screw to 2.2 N´m (20 in. lbs.).
(4) Install the eyelet of the battery positive cable
PDC take out onto the forward B(+) terminal stud in
the PDC.
(5) Install and tighten the nut that secures the
eyelet of the battery positive cable PDC take out to
the forward B(+) terminal stud in the PDC. Tighten
the nut to 8.4 N´m (75 in. lbs.).
(6) Install the eyelet of the battery negative cable
generator output take out onto the rearward B(+) ter-
minal stud in the PDC.
(7) Install and tighten the nut that secures the
eyelet of the battery negative cable generator output
take out to the rearward B(+) terminal stud in the
PDC. Tighten the nut to 75 in. lbs.
(8) Reconnect the engine wire harness in-line con-
nector to the PDC.
(9) Install and tighten the screw that secures the
engine wire harness in-line connector to the PDC.
Tighten the screw until a distinct audible click is
heard.
(10) Install and latch the cover onto the PDC.
(11) Engage each of the retainers that secure the
headlamp and dash wire harness to the vehicle body
and chassis components. Refer toConnector Loca-
tionsin the index of this service manual for the loca-
tion of more information on the headlamp and dash
wire harness retainer locations.
(12) Install all of the fasteners that secure each of
the headlamp and dash wire harness ground eyelets
to the vehicle body and chassis components. Refer to
Connector Locationsin the index of this service
manual for the location of more information on the
ground eyelet locations.
(13) Reconnect each of the headlamp and dash
wire harness connectors. Refer toConnector Loca-
tionsin the index of this service manual for the loca-
tion of more information on the headlamp and dash
wire harness connector locations.
(14) Reconnect the battery negative cable.POWER OUTLET
DESCRIPTION
An accessory power outlet is standard equipment
on this model. The power outlet is installed in the
instrument panel below the cigar lighter and next to
the ash receiver, which is located near the center of
Fig. 9 Battery and Generator Connections to PDC
1 - NUTS
2 - BATTERY POSITIVE CABLE
3 - BATTERY NEGATIVE CABLE
4 - POWER DISTRIBUTION CENTER
5 - CABLE EYELETS
Fig. 10 Power Distribution Center
1 - FENDER INNER SHIELD
2 - INNER WHEEL HOUSE
3 - SCREW
4 - SCREW
5 - POWER DISTRIBUTION CENTER
BR/BE8W-97 POWER DISTRIBUTION 8W - 97 - 9
POWER DISTRIBUTION CENTER (Continued)

the instrument panel, below the radio. The power
outlet base is secured by a snap fit within the instru-
ment panel. A plastic protective cap snaps into the
power outlet base when the power outlet is not being
used, and hangs from the power outlet base mount
by an integral bail strap while the power outlet is in
use.
The power outlet receptacle unit and the accessory
power outlet protective cap are available for service.
The power outlet receptacle cannot be repaired and,
if faulty or damaged, it must be replaced.
OPERATION
The power outlet base or receptacle shell is con-
nected to ground, and an insulated contact in the
bottom of the shell is connected to battery current.
The power outlet receives battery voltage from a fuse
in the Power Distribution Center (PDC) at all times.
While the power outlet is very similar to a cigar
lighter base unit, it does not include the two small
spring-clip retainers inside the bottom of the recepta-
cle shell that are used to secure the cigar lighter
heating element to the insulated contact.
DIAGNOSIS & TESTING - POWER OUTLET
For complete circuit diagrams, refer toPower
Outletin Wiring Diagrams.
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, REFER TO GROUP 8M - PASSIVE
RESTRAINT SYSTEMS BEFORE ATTEMPTING ANY
STEERING WHEEL, STEERING COLUMN, OR
INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
SERVICE. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Check the fused B(+) fuse in the Power Distri-
bution Center (PDC). If OK, go to Step 2. If not OK,
repair the shorted circuit or component as required
and replace the faulty fuse.
(2) Check for battery voltage at the fused B(+) fuse
in the PDC. If OK, go to Step 3. If not OK, repair the
open fused B(+) circuit to the battery as required.
(3) Remove the plastic protective cap from the
power outlet receptacle. Check for continuity between
the inside circumference of the power outlet recepta-
cle and a good ground. There should be continuity. If
OK, go to Step 4. If not OK, go to Step 5.
(4) Check for battery voltage at the insulated con-
tact located at the back of the power outlet recepta-
cle. If not OK, go to Step 5.
(5) Disconnect and isolate the battery negative
cable. Remove the power outlet receptacle from the
instrument panel. Disconnect the wire harness con-
nector from the power outlet receptacle. Check forcontinuity between the ground circuit cavity of the
power outlet wire harness connector and a good
ground. There should be continuity. If OK, go to Step
6. If not OK, repair the open ground circuit to ground
as required.
(6) Connect the battery negative cable. Check for
battery voltage at the fused B(+) circuit cavity of the
power outlet wire harness connector. If OK, replace
the faulty power outlet receptacle. If not OK, repair
the open fused B(+) circuit to the PDC fuse as
required.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Pull the cigar lighter knob and element out of
the cigar lighter receptacle base, or unsnap the pro-
tective cap from the power outlet receptacle base
(Fig. 11).
(3) Look inside the cigar lighter or power outlet
receptacle base and note the position of the rectangu-
lar retaining bosses of the mount that secures the
receptacle base to the instrument panel (Fig. 12).
(4) Insert a pair of external snap ring pliers into
the cigar lighter or power outlet receptacle base and
engage the tips of the pliers with the retaining
bosses of the mount.
(5) Squeeze the pliers to disengage the mount
retaining bosses from the receptacle base and, using
a gentle rocking motion, pull the pliers and the
receptacle base out of the mount.
Fig. 11 Cigar Lighter and Power Outlet
1 - RECEPTACLE BASE
2 - KNOB & ELEMENT
3 - MOUNT
4 - WIRE HARNESS CONNECTOR
5 - POWER OUTLET
8W - 97 - 10 8W-97 POWER DISTRIBUTIONBR/BE
POWER OUTLET (Continued)

(6) Pull the receptacle base away from the instru-
ment panel far enough to access the instrument
panel wire harness connector.
(7) Disconnect the instrument panel wire harness
connector from the cigar lighter or power outlet
receptacle base connector receptacle.
(8) Remove the cigar lighter or power outlet mount
from the instrument panel.
INSTALLATION
(1) Install the cigar lighter or power outlet mount
into the instrument panel.
(2) Reconnect the instrument panel wire harness
connector to the cigar lighter or power outlet recep-
tacle base connector receptacle.
(3) Align the splines on the outside of the cigar
lighter or power outlet receptacle base connector
receptacle with the grooves on the inside of the
mount.
(4) Press firmly on the cigar lighter or power out-
let receptacle base until the retaining bosses of the
mount are fully engaged in their receptacles.
(5) Install the cigar lighter knob and element into
the cigar lighter receptacle base, or the protective cap
into the power outlet receptacle base.
(6) Reconnect the battery negative cable.
Fig. 12 Cigar Lighter and Power Outlet Remove/
Install
1 - KNOB AND ELEMENT
2 - RETAINING BOSSES-ENGAGE PLIERS HERE
3 - BASE
4 - PARTIALLY REMOVED
5 - EXTERNAL SNAP-RING PLIERS
6 - MOUNT
7 - BASE
BR/BE8W-97 POWER DISTRIBUTION 8W - 97 - 11
POWER OUTLET (Continued)

ENGINE
TABLE OF CONTENTS
page page
ENGINE 3.9L.............................. 1
ENGINE 5.2L............................. 59
ENGINE 5.9L............................ 116ENGINE 8.0L............................ 171
ENGINE 5.9L DIESEL..................... 229
ENGINE 3.9L
TABLE OF CONTENTS
page page
ENGINE 3.9L
DESCRIPTION............................3
DIAGNOSIS AND TESTING..................3
ENGINE DIAGNOSIS - INTRODUCTION.......3
PERFORMANCE........................4
MECHANICAL..........................6
LUBRICATION..........................8
CYLINDER COMPRESSION PRESSURE......9
CYLINDER COMBUSTION PRESSURE
LEAKAGE..............................9
REAR SEAL AREA LEAKS................10
STANDARD PROCEDURE..................10
CYLINDER BORE HONING...............10
HYDROSTATIC LOCK....................11
REPAIR DAMAGED OR WORN THREADS....11
FORM-IN-PLACE GASKETS AND SEALERS . . . 11
REMOVAL..............................12
INSTALLATION...........................13
SPECIFICATIONS........................14
SPECIAL TOOLS.........................19
AIR CLEANER ELEMENT
REMOVAL..............................21
INSTALLATION...........................21
CYLINDER HEAD
DESCRIPTION...........................22
OPERATION.............................22
DIAGNOSIS AND TESTING.................22
CYLINDER HEAD GASKET FAILURE........22
REMOVAL..............................23
CLEANING..............................23
INSPECTION............................23
INSTALLATION...........................23
CYLINDER HEAD COVER(S)
REMOVAL..............................24
CLEANING..............................24INSPECTION............................24
INSTALLATION...........................24
INTAKE/EXHAUST VALVES & SEATS
DESCRIPTION...........................25
STANDARD PROCEDURE..................25
VALVES, GUIDES AND SPRINGS...........25
REMOVAL..............................27
CLEANING..............................27
INSPECTION............................27
INSTALLATION...........................28
ENGINE BLOCK
CLEANING..............................28
INSPECTION............................28
CAMSHAFT & BEARINGS (IN BLOCK)
REMOVAL..............................29
INSTALLATION...........................29
CONNECTING ROD BEARINGS
STANDARD PROCEDURE..................31
CONNECTING ROD BEARING FITTING......31
CRANKSHAFT
DESCRIPTION...........................31
OPERATION.............................31
REMOVAL..............................31
INSTALLATION...........................32
CRANKSHAFT MAIN BEARINGS
DESCRIPTION...........................32
OPERATION.............................32
STANDARD PROCEDURE..................33
MAIN BEARING FITTING.................33
REMOVAL..............................33
INSTALLATION...........................34
CRANKSHAFT OIL SEAL - FRONT
DESCRIPTION...........................34
OPERATION.............................34
REMOVAL..............................34
BR/BEENGINE 9 - 1

INSTALLATION...........................34
CRANKSHAFT OIL SEAL - REAR
DESCRIPTION...........................34
OPERATION.............................34
REMOVAL..............................35
INSTALLATION...........................35
DISTRIBUTOR BUSHING
REMOVAL..............................37
INSTALLATION...........................37
HYDRAULIC LIFTERS (CAM IN BLOCK)
DIAGNOSIS AND TESTING.................38
HYDRAULIC TAPPETS...................38
REMOVAL..............................39
CLEANING..............................39
INSTALLATION...........................39
PISTON & CONNECTING ROD
DESCRIPTION...........................40
STANDARD PROCEDURE..................40
PISTON FITTING.......................40
REMOVAL..............................40
CLEANING..............................41
INSPECTION............................41
INSTALLATION...........................41
PISTON RINGS
STANDARD PROCEDURE..................41
PISTON RING FITTING..................41
VIBRATION DAMPER
REMOVAL..............................42
INSTALLATION...........................42
FRONT MOUNT
REMOVAL..............................43
INSTALLATION...........................43
REAR MOUNT
REMOVAL..............................44
INSTALLATION...........................44
LUBRICATION
DESCRIPTION...........................45
OPERATION.............................45
DIAGNOSIS AND TESTING.................47
ENGINE OIL PRESSURE.................47
ENGINE OIL LEAKS.....................47
OIL
STANDARD PROCEDURE..................47
ENGINE OIL...........................47OIL FILTER
REMOVAL..............................48
INSTALLATION...........................48
OIL PAN
REMOVAL..............................48
CLEANING..............................49
INSPECTION............................49
INSTALLATION...........................49
OIL PRESSURE SENSOR/SWITCH
DESCRIPTION...........................49
OPERATION.............................49
OIL PUMP
REMOVAL..............................50
DISASSEMBLY...........................50
CLEANING..............................50
INSPECTION............................50
ASSEMBLY.............................51
INSTALLATION...........................52
INTAKE MANIFOLD
DESCRIPTION...........................52
OPERATION.............................52
DIAGNOSIS AND TESTING.................53
INTAKE MANIFOLD LEAKAGE.............53
REMOVAL..............................53
CLEANING..............................53
INSPECTION............................53
INSTALLATION...........................53
EXHAUST MANIFOLD
DESCRIPTION...........................55
OPERATION.............................55
REMOVAL..............................55
CLEANING..............................55
INSPECTION............................55
INSTALLATION...........................55
TIMING BELT / CHAIN COVER(S)
REMOVAL..............................56
INSTALLATION...........................56
TIMING BELT/CHAIN TENSIONER
DESCRIPTION...........................57
OPERATION.............................57
TIMING BELT/CHAIN AND SPROCKETS
REMOVAL..............................57
INSPECTION............................58
INSTALLATION...........................58
9 - 2 ENGINE 3.9LBR/BE

ENGINE 3.9L
DESCRIPTION
The 3.9 Liter (238 CID) six-cylinder engine is a
V-Type, lightweight, single cam, overhead valve
engine with hydraulic roller tappets. This engine is
designed to use unleaded fuel.
The engine lubrication system consists of a rotor
type oil pump and a full-flow oil filter.
The cylinders are numbered from front to rear; 1,
3, 5 on the left bank and 2, 4, 6 on the right bank.
The firing order is 1-6-5-4-3-2 (Fig. 1).
The engine serial number is stamped into a
machined pad located on the left front corner of the
cylinder block. When component part replacement is
necessary, use the engine type and serial number for
reference (Fig. 2).
DIAGNOSIS AND TESTINGÐENGINE
DIAGNOSIS - INTRODUCTION
Engine diagnosis is helpful in determining the
causes of malfunctions not detected and remedied by
routine maintenance.
These malfunctions may be classified as either
mechanical (e.g., a strange noise), or performance
(e.g., engine idles rough and stalls).
(Refer to 9 - ENGINE - DIAGNOSIS AND TEST-
ING - Preformance) or (Refer to 9 - ENGINE - DIAG-
NOSIS AND TESTING - Mechanical). Refer to 14 -
FUEL SYSTEM for fuel system diagnosis.
Additional tests and diagnostic procedures may be
necessary for specific engine malfunctions that can-
not be isolated with the Service Diagnosis charts.
Information concerning additional tests and diagno-
sis is provided within the following:
²Cylinder Compression Pressure Test
²Cylinder Combustion Pressure Leakage Test
²Cylinder Head Gasket Failure Diagnosis
²Intake Manifold Leakage Diagnosis
²Lash Adjuster (Tappet) Noise Diagnosis
²Engine Oil Leak Inspection
Fig. 1 Firing Order
Fig. 2 Engine Identification (Serial) Number
BR/BEENGINE 3.9L 9 - 3
ENGINE 3.9L (Continued)