2003 DODGE RAM ignition

The Auto Shutdown (ASD) relay provides battery
voltage to each ignition coil.
The ignition system consists of:
²6 Spark Plugs
²6 Separate Ignition Coils
²2 Knock Sensors
²Powertrain Control Module (PCM)
²Also to be considered part of the ignition system
are certain inputs from the Crankshaft Position,
Camshaft Position, Throttle Position, 2 knock and
MAP Sensors
4.7L V-8 ENGINE
The 4.7L V-8 engine uses a separate ignition coil for
each cylinder. The one-piece coil bolts directly to the
cylinder head. Rubber boots seal the secondary termi-
nal ends of the coils to the top of all 8 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 4.7L engine.
Two knock sensors (one for each cylinder bank) are
used to help control spark knock.
The Auto Shutdown (ASD) relay provides battery
voltage to each ignition coil.
The ignition system consists of:
²8 Spark Plugs
²8 Separate Ignition Coils
²2 Knock Sensors
²Powertrain Control Module (PCM)
²Also to be considered part of the ignition system
are certain inputs from the Crankshaft Position,
Camshaft Position, Throttle Position, 2 knock and
MAP Sensors
5.7L V-8 ENGINE
For additional information, also refer to Igni-
tion Coil Description and Operation.
The 5.7L V-8 engine is equipped with 16 spark
plugs. Two plugs are used for each cylinder. The 5.7L
is also equipped with 8 separate and independent
ignition coils. The one-piece coil bolts directly to the
cylinder head cover and attaches the coils secondary
output terminal directly to a spark plug using a rub-
ber boot seal. Each coil is also equipped with a sec-
ond output terminal. This second terminal connects a
conventional spark plug cable directly to a spark
plug on the opposite cylinder bank. A separate pri-
mary electrical connector is used for each coil.
Eight conventional spark plug cables are used with
the 5.7L. These cables connect a coil on one cylinder
bank, directly to a spark plug on the opposite cylin-
der bank. The cables are placed and routed in a spe-
cial plastic loom to keep them separated. This loom is
clipped to the intake manifold. To prevent a miss-
match of cables, a corresponding spark plug / coil
number is displayed on each plug cable: 1/6, 2/3, 4/7and 5/8. These numbers can also be found on the top
of the intake manifold to the right of the throttle
body (Fig. 1).
Two knock sensors (one for each cylinder bank) are
used to help control spark knock.
The 5.7L engine will not use a conventional distrib-
utor.
The ignition system consists of:
²16 Spark Plugs (2 per cylinder)
²
8 Separate, Dual-Secondary Output, Ignition Coils
²2 Knock Sensors
²8 Secondary Ignition Cables
²Powertrain Control Module (PCM)
²Also to be considered part of the ignition system
are certain inputs from the Crankshaft Position,
Camshaft Position, Throttle Position, 2 knock and
MAP Sensors
5.9L V-8 ENGINE
The 5.9L V-8 ignition system will use a conven-
tional distributor and 1 remotely mounted coil. Con-
ventional spark plug cables are used with the 5.9L.
Knock sensors are not used with the 5.9L engine.
The ignition system consists of:
²8 Spark Plugs
²1 Ignition Coil
²Secondary Ignition Cables
²Distributor (contains rotor and camshaft position
sensor)
²Powertrain Control Module (PCM)
Fig. 1 FIRING ORDER / CABLE ROUTING - 5.7L V-8
ENGINE
1 - TOP OF INTAKE MANIFOLD
2 - CYLINDER FIRING ORDER (IGNITION COIL NUMBER)
3 - CORRESPONDING SPARK PLUG NUMBER
8I - 2 IGNITION CONTROLDR
IGNITION CONTROL (Continued)

²Also to be considered part of the ignition system
are certain inputs from the Crankshaft Position, Cam-
shaft Position, Throttle Position and MAP Sensors
8.0L V-10 ENGINE
. The 8.0L V-10 engine is equipped with 2 remote
coil packs. Conventional spark plug cables are used
with the 8.0L engine. The 8.0L engine will not use a
conventional distributor
The ignition coils are individually fired, but each
coil is a dual output. Refer to Ignition Coil for addi-
tional information.Knock sensors are not used with the 8.0L engine.
The ignition system consists of:
²10 Spark Plugs
²2 Ignition Coil packs containing 10 individual
coils
²10 Secondary Ignition Cables
²Powertrain Control Module (PCM)
²Also to be considered part of the ignition system
are certain inputs from the Crankshaft Position,
Camshaft Position, Throttle Position and MAP Sen-
sors
SPECIFICATIONS
SPECIFICATIONS - TORQUE - IGNITION
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Camshaft Position Sensor - 3.7L V-6 Engine 12 - 106
Camshaft Position Sensor - 4.7L V-8 Engine 12 - 106
Camshaft Position Sensor - 5.7L V-8 Engine 12 9 105
Camshaft Position Sensor - 8.0L V-10 Engine 6 - 50
Crankshaft Position Sensor - 3.7L V-6 Engine 28 21 205
Crankshaft Position Sensor - 4.7L V-8 Engine 28 21 205
Crankshaft Position Sensor - 5.7L V-8 Engine 12 9 105
Crankshaft Position Sensor - 5.9L V-8 Engine 8 - 70
Crankshaft Position Sensor - 8.0L V-10 Engine 8 - 70
Distributor Hold Down Bolt - 5.9L V-8 Engine 23 17 -
Ignition Coil Mounting - 5.9L V-8 Engine
(if tapped bolts are used)5-50
Ignition Coil Mounting - 5.9L V-8 Engine
(if nuts/bolts are used)11 - 100
Ignition Coil Mounting - 3.7L V-6 Engine 8 - 70
Ignition Coil Mounting - 4.7L V-8 Engine 8 - 70
Ignition Coil Mounting - 5.7L V-8 Engine 12 9 105 (  20)
Ignition Coil Mounting - 8.0L V-10 Engine 10 - 90
* Knock Sensor - 3.7L V-6 Engine 20 15 176
* Knock Sensor - 4.7L V-8 Engine 20 15 176
* Knock Sensor - 5.7L V-8 Engine 20 15 176
Spark Plugs - 3.7L V-6 Engine 27 20 -
Spark Plugs - 4.7L V-8 Engine 27 20 -
** Spark Plugs - 5.7L V-8 Engine 18 (  3) 13 (  2) -
Spark Plugs - 5.9L V-8 Engine 41 30 -
Spark Plugs - 8.0L V-10 Engine 41 30 -
* Do not apply any sealant, thread-locker or adhesive
to bolts. Poor sensor performance may result.
** Torque critical tapered design. Do not exceed 15 ft.
lbs.
DRIGNITION CONTROL 8I - 3
IGNITION CONTROL (Continued)

ENGINE FIRING ORDER - 3.7L V-6
1-6-5-4-3-2
ENGINE FIRING ORDER ± 4.7L V-8
FIRING ORDER / CABLE ROUTING ± 5.7L V-8
ENGINE
Eight conventional spark plug cables are used with
the 5.7L. These cables connect a coil on one cylinder
bank, directly to a spark plug on the opposite cylin-
der bank. The cables are placed and routed in a spe-
cial plastic loom to keep them separated. This loom is
clipped to the intake manifold. To prevent a miss-
match of cables, a corresponding spark plug / coil
number is displayed on each plug cable: 1/6, 2/3, 4/7
and 5/8. These numbers can also be found on the top
of the intake manifold to the right of the throttle
body (Fig. 2).
ENGINE FIRING ORDER - 5.9L V-8
Fig. 2 FIRING ORDER / CABLE ROUTING - 5.7L V-8
ENGINE
1 - TOP OF INTAKE MANIFOLD
2 - CYLINDER FIRING ORDER (IGNITION COIL NUMBER)
3 - CORRESPONDING SPARK PLUG NUMBER
8I - 4 IGNITION CONTROLDR
IGNITION CONTROL (Continued)

SPARK PLUG CABLE ORDER ± 8.0L V-10
ENGINE
SPARK PLUG CABLE RESISTANCE
MINIMUM MAXIMUM
250 Ohms Per Inch 1000 Ohms Per Inch
3000 Ohms Per Foot 12,000 Ohms Per Foot
SPARK PLUGS
ENGINE PLUG TYPE ELECTRODE GAP
3.7L V-6 ZFR6F - 11G (NGK) 1.1 (0.042 in.)
4.7L V-8 RC12MCC4 1.01 mm (.040 in.)
5.7L V-8 Champion - RE14MCC4 1.14 mm (.045 in.)
5.9L V-8 RC12LC4 1.01 mm (.040 in.)
8.0L V-10 QC9MC4 1.14 mm (.045 in.)
SPARK PLUG CABLE ORDER ± 8.0L V-10 ENGINE
DRIGNITION CONTROL 8I - 5
IGNITION CONTROL (Continued)

IGNITION COIL RESISTANCE - 3.7L V-6
PRIMARY RESISTANCE
21-27ÉC (70-80ÉF)SECONDARY
RESISTANCE 21-27ÉC
(70-80ÉF)
0.6 - 0.9 Ohms 6,000 - 9,000 Ohms
IGNITION COIL RESISTANCE - 4.7L V-8
PRIMARY
RESISTANCE 21-27ÉC
(70-80ÉF)SECONDARY
RESISTANCE 21-27ÉC
(70-80ÉF)
0.6 - 0.9 Ohms 6,000 - 9,000 Ohms
IGNITION COIL RESISTANCE - 5.7L V-8
PRIMARY RESISTANCE @ 21-27ÉC (70-80ÉF)
0.558 - 0.682 Ohms
(Plus or Minus 10% @ 70-80É F)
IGNITION COIL RESISTANCE - 5.9L
COIL MANUFACTURERPRIMARY RESISTANCE
21-27ÉC (70-80ÉF)SECONDARY RESISTANCE 21-27ÉC
(70-80ÉF)
Diamond 0.97 - 1.18 Ohms 11,300 - 15,300 Ohms
Toyodenso 0.95 - 1.20 Ohms 11,300 - 13,300 Ohms
IGNITION COIL RESISTANCE ± 8.0L V-10
ENGINE
Primary Resistance: 0.53-0.65 Ohms. Test across the
primary connector. Refer to text for test procedures.
Secondary Resistance: 10.9-14.7K Ohms. Test across
the individual coil towers. Refer to text for test
procedures.
IGNITION TIMING
Ignition timing is not adjustable on any engine.
AUTOMATIC SHUT DOWN
RELAY
DESCRIPTION - PCM OUTPUT
The 5±pin, 12±volt, Automatic Shutdown (ASD)
relay is located in the Power Distribution Center
(PDC). Refer to label on PDC cover for relay location.
OPERATION
OPERATION - PCM OUTPUT
The ASD relay supplies battery voltage (12+ volts)
to the fuel injectors and ignition coil(s). With certain
emissions packages it also supplies 12±volts to the
oxygen sensor heating elements.The ground circuit for the coil within the ASD
relay is controlled by the Powertrain Control Module
(PCM). The PCM operates the ASD relay by switch-
ing its ground circuit on and off.
The ASD relay will be shut±down, meaning the
12±volt power supply to the ASD relay will be de-ac-
tivated by the PCM if:
²the ignition key is left in the ON position. This
is if the engine has not been running for approxi-
mately 1.8 seconds.
²there is a crankshaft position sensor signal to
the PCM that is lower than pre-determined values.
OPERATION - ASD SENSE - PCM INPUT
A 12 volt signal at this input indicates to the PCM
that the ASD has been activated. The relay is used to
connect the oxygen sensor heater element, ignition
coil and fuel injectors to 12 volt + power supply.
This input is used only to sense that the ASD relay
is energized. If the Powertrain Control Module
(PCM) does not see 12 volts at this input when the
ASD should be activated, it will set a Diagnostic
Trouble Code (DTC).
8I - 6 IGNITION CONTROLDR
IGNITION CONTROL (Continued)

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)

3 notches, 2 notches 1 notch, 3 notches and 1 notch.
The signal from the CMP sensor is used in conjunc-
tion with the crankshaft position sensor to differenti-
ate between fuel injection and spark events. It is also
used to synchronize the fuel injectors with their
respective cylinders.
5.7L V-8
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.
The tonewheel is located at the front of the cam-
shaft (Fig. 8). As the tonewheel rotates, notches (Fig.
8) pass through the sync signal generator.
When the cam gear is rotating, the sensor will
detect the notches. Input voltage from the sensor to
the PCM will then switch from a low (approximately
0.3 volts) to a high (approximately 5 volts). When the
sensor detects a notch has passed, the input voltage
switches back low to approximately 0.3 volts.
Fig. 6 CMP OPERATION- 3.7L V-6
1 - NOTCHES
2 - RIGHT CYLINDER HEAD
3 - CMP
4 - TONEWHEEL (TARGET WHEEL)
Fig. 7 CMP AND TONEWHEEL OPERATION - 4.7L
V-8
1 - NOTCHES
2 - RIGHT CYLINDER HEAD
3 - CAMSHAFT POSITION SENSOR
4 - TONEWHEEL
Fig. 8 CMP OPERATION - 5.7L ENGINE
1 - TIMING CHAIN COVER
2 - TONEWHEEL
3 - NOTCHES
DRIGNITION CONTROL 8I - 9
CAMSHAFT POSITION SENSOR (Continued)