2003 DODGE RAM Fuel pump

with automatic transmission, place gearshift selector
lever in Park position.
(4) Verify that all lamps and accessories are
turned off.
(5) To prevent a gasoline engine from starting,
remove Automatic ShutDown (ASD) relay. To prevent
a diesel engine from starting, remove Fuel Pump
Relay. These relays are located in Power Distribution
Center (PDC). Refer to label on PDC cover for relay
location.
WARNING: IF EQUIPPED WITH DIESEL ENGINE,
ATTEMPT TO START ENGINE A FEW TIMES
BEFORE PROCEEDING WITH FOLLOWING STEP.
(6) Rotate and hold ignition switch in Start posi-
tion. Note cranking voltage and current (amperage)
draw readings shown on volt-ampere tester.
(a) If voltage reads below 9.6 volts, refer to
Starter Motorin Diagnosis and Testing. If starter
motor is OK, refer toEngine Diagnosisin 9,
Engine for further testing of engine. If starter
motor is not OK, replace faulty starter motor.
(b) If voltage reads above 9.6 volts and current
(amperage) draw reads below specifications, refer
toFeed Circuit Testin this section.
(c) If voltage reads 12.5 volts or greater and
starter motor does not turn, refer toControl Cir-
cuit Testingin this section.
(d) If voltage reads 12.5 volts or greater and
starter motor turns very slowly, refer toFeed Cir-
cuit Testin this section.
NOTE: A cold engine will increase starter current
(amperage) draw reading, and reduce battery volt-
age reading.FEED CIRCUIT TEST
The starter feed circuit test (voltage drop method)
will determine if there is excessive resistance in
high-amperage feed circuit. For complete starter wir-
ing circuit diagrams, refer 8, Wiring Diagrams.
When performing these tests, it is important to
remember that voltage drop is giving an indication of
resistance between two points at which voltmeter
probes are attached.
Example:When testing resistance of positive bat-
tery cable, touch voltmeter leads to positive battery
cable clamp and cable connector at starter solenoid.
If you probe positive battery terminal post and cable
connector at starter solenoid, you are reading com-
bined voltage drop in positive battery cable clamp-to-
terminal post connection and positive battery cable.
The following operation will require a voltmeter
accurate to 1/10 (0.10) volt. Before performing tests,
be certain that following procedures are accom-
plished:
²Battery is fully-charged and load-tested. Refer to
Batteryin 8, Battery.
²Fully engage parking brake.
²If equipped with manual transmission, place
gearshift selector lever in Neutral position and block
clutch pedal in fully depressed position. If equipped
with automatic transmission, place gearshift selector
lever in Park position.
²Verify that all lamps and accessories are turned
off.
²To prevent a gasoline engine from starting,
remove Automatic ShutDown (ASD) relay. To prevent
a diesel engine from starting, remove Fuel Pump
Relay. These relays are located in Power Distribution
Center (PDC). Refer to label on PDC cover for relay
location.
(1) Connect positive lead of voltmeter to negative
battery cable terminal post. Connect negative lead of
voltmeter to negative battery cable clamp (Fig. 2).
Rotate and hold ignition switch in Start position.
Observe voltmeter. If voltage is detected, correct poor
contact between cable clamp and terminal post.
Note: Certain diesel equipped models use dual
batteries. If equipped with dual battery system,
procedure must be performed twice, once for
each battery.
(2) Connect positive lead of voltmeter to positive
battery terminal post. Connect negative lead of volt-
meter to battery positive cable clamp (Fig. 3). Rotate
and hold ignition switch in Start position. Observe
voltmeter. If voltage is detected, correct poor contact
between cable clamp and terminal post.Note: Cer-
tain diesel equipped models use dual batteries.
If equipped with dual battery system, this pro-
cedure must be performed twice, once for each
battery.
Fig. 1 VOLTS-AMPS TESTER CONNECTIONS -
TYPICAL
1 - POSITIVE CLAMP
2 - NEGATIVE CLAMP
3 - INDUCTION AMMETER CLAMP
DRSTARTING 8F - 31
STARTING (Continued)

IGNITION CONTROL
TABLE OF CONTENTS
page page
IGNITION CONTROL
DESCRIPTION..........................1
SPECIFICATIONS
SPECIFICATIONS - TORQUE - IGNITION....3
ENGINE FIRING ORDER - 3.7L V-6.........4
ENGINE FIRING ORDER ± 4.7L V-8........4
FIRING ORDER / CABLE ROUTING ± 5.7L
V-8 ENGINE...........................4
ENGINE FIRING ORDER - 5.9L V-8.........4
SPARK PLUG CABLE ORDER ± 8.0L V-10
ENGINE..............................5
SPARK PLUG CABLE RESISTANCE........5
SPARK PLUGS........................5
IGNITION COIL RESISTANCE - 3.7L V-6.....6
IGNITION COIL RESISTANCE - 4.7L V-8.....6
IGNITION COIL RESISTANCE - 5.7L V-8.....6
IGNITION COIL RESISTANCE - 5.9L........6
IGNITION COIL RESISTANCE ± 8.0L V-10
ENGINE..............................6
IGNITION TIMING......................6
AUTOMATIC SHUT DOWN RELAY
DESCRIPTION - PCM OUTPUT.............6
OPERATION
OPERATION - PCM OUTPUT.............6
OPERATION - ASD SENSE - PCM INPUT....6
DIAGNOSIS AND TESTING - ASD AND FUEL
PUMP RELAYS........................7
REMOVAL.............................7
INSTALLATION..........................8
CAMSHAFT POSITION SENSOR
DESCRIPTION..........................8
OPERATION............................8
REMOVAL.............................11
INSTALLATION.........................14
DISTRIBUTOR
DESCRIPTION.........................16
OPERATION...........................16
REMOVAL.............................17INSTALLATION.........................18
DISTRIBUTOR CAP
DIAGNOSIS AND TESTING - DISTRIBUTOR
CAP - 5.9L V-8........................18
DISTRIBUTOR ROTOR
DIAGNOSIS AND TESTING - DISTRIBUTOR
ROTOR - 5.9L V-8.....................19
IGNITION COIL
DESCRIPTION.........................19
OPERATION...........................20
REMOVAL.............................23
INSTALLATION.........................24
KNOCK SENSOR
DESCRIPTION.........................25
OPERATION...........................25
REMOVAL.............................25
INSTALLATION.........................26
SPARK PLUG
DESCRIPTION.........................27
DIAGNOSIS AND TESTING - SPARK PLUG
CONDITIONS.........................27
REMOVAL.............................30
CLEANING
CLEANING AND ADJUSTMENT...........31
INSTALLATION.........................31
IGNITION COIL CAPACITOR
DESCRIPTION.........................33
OPERATION...........................33
REMOVAL.............................33
INSTALLATION.........................33
SPARK PLUG CABLE
DESCRIPTION.........................33
OPERATION...........................33
DIAGNOSIS AND TESTING - SPARK PLUG
CABLES............................33
REMOVAL.............................34
INSTALLATION.........................35
IGNITION CONTROL
DESCRIPTION
The ignition system is controlled by the Powertrain
Control Module (PCM) on all engines.
3.7L V-6 ENGINE
The 3.7L V-6 engine uses a separate ignition coil
for each cylinder. The one-piece coil bolts directly tothe cylinder head. Rubber boots seal the secondary
terminal ends of the coils to the top of all 6 spark
plugs. A separate electrical connector is used for each
coil.
Because of coil design, spark plug cables (second-
ary cables) are not used. A distributor is not used
with the 3.7L engine.
Two knock sensors (one for each cylinder bank) are
used to help control spark knock.
DRIGNITION CONTROL 8I - 1

DIAGNOSIS AND TESTING - ASD AND FUEL
PUMP RELAYS
The following description of operation and
tests apply only to the Automatic Shutdown
(ASD) and fuel pump relays. The terminals on the
bottom of each relay are numbered. Two different
types of relays may be used, (Fig. 3) or (Fig. 4).
²Terminal number 30 is connected to battery volt-
age. For both the ASD and fuel pump relays, termi-
nal 30 is connected to battery voltage at all times.
²The PCM grounds the coil side of the relay
through terminal number 85.²Terminal number 86 supplies voltage to the coil
side of the relay.
²When the PCM de-energizes the ASD and fuel
pump relays, terminal number 87A connects to termi-
nal 30. This is the Off position. In the off position,
voltage is not supplied to the rest of the circuit. Ter-
minal 87A is the center terminal on the relay.
²When the PCM energizes the ASD and fuel
pump relays, terminal 87 connects to terminal 30.
This is the On position. Terminal 87 supplies voltage
to the rest of the circuit.
The following procedure applies to the ASD and
fuel pump relays.
(1) Remove relay from connector before testing.
(2) With the relay removed from the vehicle, use
an ohmmeter to check the resistance between termi-
nals 85 and 86. The resistance should be 75 ohms +/-
5 ohms.
(3) Connect the ohmmeter between terminals 30
and 87A. The ohmmeter should show continuity
between terminals 30 and 87A.
(4) Connect the ohmmeter between terminals 87
and 30. The ohmmeter should not show continuity at
this time.
(5) Connect one end of a jumper wire (16 gauge or
smaller) to relay terminal 85. Connect the other end
of the jumper wire to the ground side of a 12 volt
power source.
(6) Connect one end of another jumper wire (16
gauge or smaller) to the power side of the 12 volt
power source.Do not attach the other end of the
jumper wire to the relay at this time.
WARNING: DO NOT ALLOW OHMMETER TO CON-
TACT TERMINALS 85 OR 86 DURING THIS TEST.
DAMAGE TO OHMMETER MAY RESULT.
(7) Attach the other end of the jumper wire to
relay terminal 86. This activates the relay. The ohm-
meter should now show continuity between relay ter-
minals 87 and 30. The ohmmeter should not show
continuity between relay terminals 87A and 30.
(8) Disconnect jumper wires.
(9) Replace the relay if it did not pass the continu-
ity and resistance tests. If the relay passed the tests,
it operates properly. Check the remainder of the ASD
and fuel pump relay circuits. Refer to 8, Wiring Dia-
grams.
REMOVAL
The ASD relay is located in the Power Distribution
Center (PDC) (Fig. 5). Refer to label on PDC cover
for relay location.
(1) Remove PDC cover.
(2) Remove relay from PDC.
Fig. 3 TYPE 1 RELAY (ISO MICRO RELAY)
Fig. 4 ASD AND FUEL PUMP RELAY TERMINALSÐ
TYPE 2
TERMINAL LEGEND
NUMBER IDENTIFICATION
30 COMMON FEED
85 COIL GROUND
86 COIL BATTERY
87 NORMALLY OPEN
87A NORMALLY CLOSED
DRIGNITION CONTROL 8I - 7
AUTOMATIC SHUT DOWN RELAY (Continued)

(3) Check condition of relay terminals and PDC
connector terminals for damage or corrosion. Repair
if necessary before installing relay.
(4) Check for pin height (pin height should be the
same for all terminals within the PDC connector).
Repair if necessary before installing relay.
INSTALLATION
The ASD relay is located in the Power Distribution
Center (PDC) (Fig. 5). Refer to label on PDC cover
for relay location.
(1) Install relay to PDC.
(2) Install cover to PDC.
CAMSHAFT POSITION
SENSOR
DESCRIPTION
3.7L V-6
The Camshaft Position Sensor (CMP) on the 3.7L
6-cylinder engine is bolted to the right-front side of
the right cylinder head.
4.7L V-8
The Camshaft Position Sensor (CMP) on the 4.7L
V-8 engine is bolted to the right-front side of the
right cylinder head.
5.7L V-8
The Camshaft Position Sensor (CMP) on the 5.7L
V-8 engine is located below the generator on the tim-
ing chain / case cover on the right/front side of
engine.
5.9L Diesel
The Camshaft Position Sensor (CMP) on the 5.9L
diesel engine is located below the fuel injection
pump. It is bolted to the back of the timing gear
cover.
5.9L V-8 Gas
The Camshaft Position Sensor (CMP) on the 5.9L
V-8 engine is located inside the distributor.
8.0L V±10
The Camshaft Position Sensor (CMP) on the 8.0L
V-10 engine is located on the timing chain / case
cover on the left/front side of engine.
OPERATION
3.7L V-6
The Camshaft Position Sensor (CMP) sensor on the
3.7L V-6 engine contains a hall effect device referred
to as a sync signal generator. A rotating target wheel
(tonewheel) for the CMP is located at the front of the
camshaft for the right cylinder head (Fig. 6). This
sync signal generator detects notches located on a
tonewheel. As the tonewheel rotates, the notches
pass through the sync signal generator. The signal
from the CMP sensor is used in conjunction with the
Crankshaft Position Sensor (CKP) to differentiate
between fuel injection and spark events. It is also
used to synchronize the fuel injectors with their
respective cylinders.
When the leading edge of the tonewheel notch
enters the tip of the CMP, the interruption of mag-
netic field causes the voltage to switch high, result-
ing in a sync signal of approximately 5 volts.
When the trailing edge of the tonewheel notch
leaves then tip of the CMP, the change of the mag-
netic field causes the sync signal voltage to switch
low to 0 volts.
4.7L V-8
The CMP sensor on the 4.7L engine contains a hall
effect device called a sync signal generator to gener-
ate a fuel sync signal. This sync signal generator
detects notches located on a tonewheel. The tone-
wheel is located at the front of the camshaft for the
right cylinder head (Fig. 7). As the tonewheel rotates,
the notches pass through the sync signal generator.
The pattern of the notches (viewed counter-clockwise
from front of engine) is: 1 notch, 2 notches, 3 notches,
Fig. 5 PDC LOCATION
1 - BATTERY
2 - PDC (POWER DISTRIBUTION CENTER)
8I - 8 IGNITION CONTROLDR
AUTOMATIC SHUT DOWN RELAY (Continued)

5.9L V-8 Gas
The CMP sensor on the 5.9L V-8 engine contains a
hall effect device called a sync signal generator to
generate a fuel sync signal. This sync signal genera-
tor detects a rotating pulse ring (shutter) (Fig. 9) on
the distributor shaft. The pulse ring rotates 180
degrees through the sync signal generator. Its signal
is used in conjunction with the Crankshaft Position
(CKP) sensor to differentiate between fuel injection
and spark events. It is also used to synchronize the
fuel injectors with their respective cylinders.
When the leading edge of the pulse ring (shutter)
enters the sync signal generator, the following occurs:
The interruption of magnetic field causes the voltage
to switch high resulting in a sync signal of approxi-
mately 5 volts.
When the trailing edge of the pulse ring (shutter)
leaves the sync signal generator, the following occurs:
The change of the magnetic field causes the sync sig-
nal voltage to switch low to 0 volts.
5.9L Diesel
The Camshaft Position Sensor (CMP) contains a
hall effect device. A rotating target wheel (tonewheel)
for the CMP is located on the front timing gear. This
hall effect device detects notches located on the tone-
wheel. As the tonewheel rotates, the notches pass the
tip of the CMP.
When the leading edge of the tonewheel notch
passes the tip of the CMP, the following occurs: The
interruption of magnetic field causes the voltage to
switch high resulting in a signal of approximately 5
volts.
When the trailing edge of the tonewheel notch
passes the tip of the CMP, the following occurs: Thechange of the magnetic field causes the signal voltage
to switch low to 0 volts.
The CMP (Fig. 10) provides a signal to the Engine
Control Module (ECM) at all times when the engine
is running. The ECM uses the CMP information pri-
marily on engine start-up. Once the engine is run-
ning, the ECM uses the CMP as a backup sensor for
engine speed. The Crankshaft Position Sensor (CKP)
is the primary engine speed indicator for the engine
after the engine is running.
8.0L V-10
The CMP sensor is used in conjunction with the
crankshaft position sensor to differentiate between
fuel injection and spark events. It is also used to syn-
chronize the fuel injectors with their respective cylin-
ders. The sensor generates electrical pulses. These
pulses (signals) are sent to the Powertrain Control
Module (PCM). The PCM will then determine crank-
shaft position from both the camshaft position sensor
and crankshaft position sensor.
A low and high area are machined into the cam-
shaft drive gear (Fig. 11). The sensor is positioned in
the timing gear cover so that a small air gap (Fig. 11)
exists between the face of sensor and the high
machined area of cam gear.
Fig. 9 CMP / PULSE RING - 5.9L GAS ENGINE
1 - SYNC SIGNAL GENERATOR
2 - CAMSHAFT POSITION SENSOR
3 - PULSE RING
4 - DISTRIBUTOR ASSEMBLY
Fig. 10 5.9L DIESEL CMP
1 - CMP
2 - FUEL INJECTION PUMP (BOTTOM)
3 - ELECTRONIC CONTROL MODULE (ECM)
4 - ECM ELEC. CONNECTOR
5 - CMP ELEC. CONNECTOR
6 - CMP MOUNTING BOLT
7 - BACK OF TIMING GEAR COVER
8I - 10 IGNITION CONTROLDR
CAMSHAFT POSITION SENSOR (Continued)

5.7L V-8
The Camshaft Position Sensor (CMP) on the 5.7L
V-8 engine is located on right side of timing chain
cover below generator (Fig. 14).
(1) Disconnect electrical connector at CMP sensor.
(2) Remove sensor mounting bolt (Fig. 15).
(3) Carefully twist sensor from cylinder head.
(4) Check condition of sensor o-ring.
5.9L Diesel
The Camshaft Position Sensor (CMP) on the 5.9L
diesel engine is located below the fuel injection
pump. It is bolted to the back of the timing gear
cover (Fig. 16).
(1) Disconnect electrical connector at CMP sensor
(Fig. 16).
(2) Remove sensor mounting bolt.
(3) Carefully twist sensor from timing gear cover.
(4) Check condition of sensor o-ring.
5.9L V-8 Gas
The Camshaft Position Sensor (CMP) is located
inside the distributor (Fig. 17).
Distributor removal is not necessary to remove
camshaft position sensor.
(1) Disconnect negative cable from battery.
(2) Remove air cleaner tubing at throttle body, and
at air filter housing.
(3) Remove distributor cap from distributor (two
screws).
Fig. 14 CMP LOCATION ± 5.7L
1 - GENERATOR
2 - CMP LOCATION
3 - ELECTRICAL CONNECTOR
Fig. 15 CMP REMOVAL / INSTALLATION ± 5.7L V-8
1 - TIMING CHAIN COVER (RIGHT/FRONT)
2 - CMP SENSOR
3 - MOUNTING BOLT
Fig. 16 5.9L DIESEL CMP
1 - CMP
2 - FUEL INJECTION PUMP (BOTTOM)
3 - ELECTRONIC CONTROL MODULE (ECM)
4 - ECM ELEC. CONNECTOR
5 - CMP ELEC. CONNECTOR
6 - CMP MOUNTING BOLT
7 - BACK OF TIMING GEAR COVER
8I - 12 IGNITION CONTROLDR
CAMSHAFT POSITION SENSOR (Continued)

WIPER MODULE
DESCRIPTION
The wiper motor bracket is secured with two
screws below the wiper motor through two rubber
insulators to the bottom of the cowl plenum panel
beneath the cowl plenum cover/grille panel (Fig. 25).
Two screws secure the top of the wiper module
bracket to the cowl plenum panel through rubber
insulators located on the outboard end of each pivot
bracket. The ends of the wiper pivot shafts that pro-
trude through dedicated openings in the cowl plenum
cover/grille panel to drive the wiper arms and blades
are the only visible components of the wiper module.
The wiper module consists of the following major
components:
²Bracket- The wiper module bracket consists of
a long tubular steel main member that has a die castpivot bracket formation near each end where the two
wiper pivots are secured. A stamped steel clamp
secures the center of the tubular member to the die
cast bracket integral to the wiper motor with two
screws.
²Crank Arm- The wiper motor crank arm is a
stamped steel unit with a slotted hole on the driven
end that is secured to the wiper motor output shaft
with a nut, and has a ball stud secured to the drive
end.
²Linkage- Two stamped steel drive links con-
nect the wiper motor crank arm to the wiper pivot
lever arms. The left side drive link has a plastic sock-
et-type bushing on each end. The right side drive
link has a plastic socket-type bushing on one end,
and a plastic sleeve-type bushing on the other end.
The socket-type bushing on one end of each drive
link is snap-fit over the ball stud on the lever arm of
its respective pivot. The right side drive link sleeve-
type bushing end is then fit over the motor crank
arm ball stud, and the other socket-type bushing of
the left side drive link is snap-fit over the exposed
end of the wiper motor crank arm ball stud.
Fig. 24 Integrated Power Module
1 - 15 - CARTRIDGE FUSE
16 - 53 - BLADE FUSE
54 - HEATED MIRROR RELAY
55 - WIPER ON/OFF RELAY
56 - A/C CONDENSER FAN RELAY
57 - ENGINE CONTROL RELAY
58 - FUEL PUMP RELAY
59 - TRANSMISSION RELAY
60 - WIPER HIGH/LOW RELAY
61 - SPARE
62 - FOG LAMP RELAY
63 - ADJUSTABLE PEDAL RELAY
64 - A/C CLUTCH RELAY
65 - SPARE
66 - O2 RELAY
67 - SPARE
68 - SPARE
69 - SPARE
70 - SPARE
71 - SPARE
72 - STARTER RELAY
73 - PARK LAMP RELAY
Fig. 25 Wiper Module
1 - PIVOT BRACKET (2)
2 - TUBE
3 - CLAMP
4 - PIVOT SHAFT (2)
5 - INSULATOR (4)
6 - LINKAGE BUSHING (4)
7 - DRIVE LINK (2)
8 - PIVOT CRANK ARM (2)
9 - PIGTAIL WIRE CONNECTOR
10 - MOTOR CRANK ARM
11 - WIPER MOTOR
8R - 22 WIPERS/WASHERSDR
WIPER HIGH/LOW RELAY (Continued)

DIAGNOSIS AND TESTING - WIPER ON/OFF
RELAY
The wiper on/off relay (Fig. 28) is located in the
Integrated Power Module (IPM) in the engine com-
partment near the battery. Refer to the appropriate
wiring information. The wiring information includes
wiring diagrams, proper wire and connector repair
procedures, details of wire harness routing and
retention, connector pin-out information and location
views for the various wire harness connectors, splices
and grounds.
(1) Remove the wiper on/off relay from the IPM.
(Refer to 8 - ELECTRICAL/WIPERS/WASHERS/
WIPER ON/OFF RELAY - REMOVAL).
(2) A relay in the de-energized position should
have continuity between terminals 87A and 30, and
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
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the cover from the Integrated Power
Module (IPM) (Fig. 29).
(3) Remove the wiper on/off relay by grasping it
firmly and pulling it straight out from the receptacle
in the IPM.
INSTALLATION
(1) Position the wiper on/off relay to the proper
receptacle in the Integrated Power Module (IPM)
(Fig. 29).
(2) Align the wiper on/off relay terminals with the
terminal cavities in the IPM receptacle.
(3) Push firmly and evenly on the top of the wiper
on/off relay until the terminals are fully seated in the
terminal cavities in the IPM receptacle.
(4) Reinstall the cover onto the IPM.
(5) Reconnect the battery negative cable.
Fig. 28 ISO Micro Relay
30 - COMMON FEED
85 - COIL GROUND
86 - COIL BATTERY
87 - NORMALLY OPEN
87A - NORMALLY CLOSED
Fig. 29 Integrated Power Module
1 - 15 - CARTRIDGE FUSE
16 - 53 - BLADE FUSE
54 - HEATED MIRROR RELAY
55 - WIPER ON/OFF RELAY
56 - A/C CONDENSER FAN RELAY
57 - ENGINE CONTROL RELAY
58 - FUEL PUMP RELAY
59 - TRANSMISSION RELAY
60 - WIPER HIGH/LOW RELAY
61 - SPARE
62 - FOG LAMP RELAY
63 - ADJUSTABLE PEDAL RELAY
64 - A/C CLUTCH RELAY
65 - SPARE
66 - O2 RELAY
67 - SPARE
68 - SPARE
69 - SPARE
70 - SPARE
71 - SPARE
72 - STARTER RELAY
73 - PARK LAMP RELAY
8R - 26 WIPERS/WASHERSDR
WIPER ON/OFF RELAY (Continued)