2002 DODGE RAM oil

SPARK PLUG OVERHEATING
Overheating is indicated by a white or gray center
electrode insulator that also appears blistered (Fig.
34). The increase in electrode gap will be consider-
ably in excess of 0.001 inch per 2000 miles of opera-
tion. This suggests that a plug with a cooler heat
range rating should be used. Over advanced ignition
timing, detonation and cooling system malfunctions
can also cause spark plug overheating.
REMOVAL
On 5.9L engines, spark plug cable heat shields are
pressed into the cylinder head to surround each cable
boot and spark plug (Fig. 35).
(1) Always remove spark plug or ignition coil
cables by grasping at the cable boot (Fig. 37). Turn
the cable boot 1/2 turn and pull straight back in a
steady motion. Never pull directly on the cable.
Internal damage to cable will result.
Fig. 32 Chipped Electrode Insulator
1 - GROUND ELECTRODE
2 - CENTER ELECTRODE
3 - CHIPPED INSULATOR
Fig. 33 Preignition Damage
1 - GROUND ELECTRODE STARTING TO DISSOLVE
2 - CENTER ELECTRODE DISSOLVED
Fig. 34 Spark Plug Overheating
1 - BLISTERED WHITE OR GRAY COLORED INSULATOR
Fig. 35 Heat ShieldsÐ5.9L Engines
1 - AIR GAP
2 - SPARK PLUG BOOT HEAT SHIELD
BR/BEIGNITION CONTROL 8I - 19
SPARK PLUG (Continued)

(2) Prior to removing the spark plug, spray com-
pressed air around the spark plug hole and the area
around the spark plug. This will help prevent foreign
material from entering the combustion chamber.
(3) Remove the spark plug using a quality socket
with a rubber or foam insert.
(4) Inspect the spark plug condition. Refer to
Spark Plug Condition in the Diagnostics and Testing
section of this group.
CLEANING
The plugs may be cleaned using commercially
available spark plug cleaning equipment. After clean-
ing, file center electrode flat with a small point file or
jewelers file before adjusting gap.
CAUTION: Never use a motorized wire wheel brush
to clean spark plugs. Metallic deposits will remain
on spark plug insulator and will cause plug misfire.
INSTALLATION
Special care should be taken when installing spark
plugs into the cylinder head spark plug wells. Be
sure the plugs do not drop into the plug wells as elec-
trodes can be damaged.
Always tighten spark plugs to the specified torque.
Over tightening can cause distortion resulting in a
change in the spark plug gap or a cracked porcelain
insulator.
When replacing the spark plug and ignition coil
cables, route the cables correctly and secure them in
the appropriate retainers. Failure to route the cables
properly can cause the radio to reproduce ignition
noise. It could cause cross ignition of the spark plugs
or short circuit the cables to ground.
(1) Start the spark plug into the cylinder head by
hand to avoid cross threading.
(2) Tighten spark plugs to 35-41 N´m (26-30 ft.
lbs.) torque.
(3) Install spark plug cables over spark plugs.
SPARK PLUG CABLE
DESCRIPTION
Spark plug cables are sometimes referred to as sec-
ondary ignition wires.
OPERATION
The spark plug cables transfer electrical current
from the ignition coil(s) and/or distributor, to individ-
ual spark plugs at each cylinder. The resistive spark
plug cables are of nonmetallic construction. The
cables provide suppression of radio frequency emis-
sions from the ignition system.
DIAGNOSIS AND TESTING - SPARK PLUG
CABLES
Cable routing is important on certain engines. To
prevent possible ignition crossfire, be sure the cables
are clipped into the plastic routing looms. Try to pre-
vent any one cable from contacting another. Before
removing cables, note their original location and
routing. Never allow one cable to be twisted around
another.
Check the spark plug cable connections for good
contact at the coil(s), distributor cap towers, and
spark plugs. Terminals should be fully seated. The
insulators should be in good condition and should fit
tightly on the coil, distributor and spark plugs. Spark
plug cables with insulators that are cracked or torn
must be replaced.
Clean high voltage ignition cables with a cloth
moistened with a non-flammable solvent. Wipe the
cables dry. Check for brittle or cracked insulation.
On 5.9L engines, spark plug cable heat shields are
pressed into the cylinder head to surround each
spark plug cable boot and spark plug (Fig. 36). These
shields protect the spark plug boots from damage
(due to intense engine heat generated by the exhaust
manifolds) and should not be removed. After the
spark plug cable has been installed, the lip of the
cable boot should have a small air gap to the top of
the heat shield (Fig. 36).
TESTING
When testing secondary cables for damage with an
oscilloscope, follow the instructions of the equipment
manufacturer.
If an oscilloscope is not available, spark plug cables
may be tested as follows:
Fig. 36 Heat ShieldsÐ5.9L Engines
1 - AIR GAP
2 - SPARK PLUG BOOT HEAT SHIELD
8I - 20 IGNITION CONTROLBR/BE
SPARK PLUG (Continued)

CAUTION: Do not leave any one spark plug cable
disconnected for longer than necessary during test-
ing. This may cause possible heat damage to the
catalytic converter. Total test time must not exceed
ten minutes.
With the engine running, remove spark plug cable
from spark plug (one at a time) and hold next to a
good engine ground. If the cable and spark plug are
in good condition, the engine rpm should drop and
the engine will run poorly. If engine rpm does not
drop, the cable and/or spark plug may not be operat-
ing properly and should be replaced. Also check
engine cylinder compression.
With the engine not running, connect one end of a
test probe to a good ground. Start the engine and run
the other end of the test probe along the entire
length of all spark plug cables. If cables are cracked
or punctured, there will be a noticeable spark jump
from the damaged area to the test probe. The cable
running from the ignition coil to the distributor cap
can be checked in the same manner. Cracked, dam-
aged or faulty cables should be replaced with resis-
tance type cable. This can be identified by the words
ELECTRONIC SUPPRESSION printed on the cable
jacket.
Use an ohmmeter to test for open circuits, exces-
sive resistance or loose terminals. If equipped,
remove the distributor cap from the distributor.Do
not remove cables from cap.Remove cable from
spark plug. Connect ohmmeter to spark plug termi-
nal end of cable and to corresponding electrode in
distributor cap. Resistance should be 250 to 1000
Ohms per inch of cable. If not, remove cable from dis-
tributor cap tower and connect ohmmeter to the ter-
minal ends of cable. If resistance is not within
specifications as found in the SPARK PLUG CABLE
RESISTANCE chart, replace the cable. Test all spark
plug cables in this manner.
SPARK PLUG CABLE RESISTANCE
MINIMUM MAXIMUM
250 Ohms Per Inch 1000 Ohms Per Inch
3000 Ohms Per Foot 12,000 Ohms Per Foot
To test ignition coil-to-distributor cap cable, do not
remove the cable from the cap. Connect ohmmeter to
rotor button (center contact) of distributor cap and
terminal at ignition coil end of cable. If resistance is
not within specifications as found in the Spark Plug
Cable Resistance chart, remove the cable from the
distributor cap. Connect the ohmmeter to the termi-
nal ends of the cable. If resistance is not within spec-
ifications as found in the Spark Plug CableResistance chart, replace the cable. Inspect the igni-
tion coil tower for cracks, burns or corrosion.
REMOVAL
CAUTION: When disconnecting a high voltage cable
from a spark plug or from the distributor cap, twist
the rubber boot slightly (1/2 turn) to break it loose
(Fig. 37). Grasp the boot (not the cable) and pull it
off with a steady, even force.
INSTALLATION
Install cables into the proper engine cylinder firing
order (Fig. 38) or (Fig. 39).
Fig. 37 Cable Removal
1 - SPARK PLUG CABLE AND BOOT
2 - SPARK PLUG BOOT PULLER
3 - TWIST AND PULL
4 - SPARK PLUG
Fig. 38 Engine Firing OrderÐ5.9L V-8 Engines
BR/BEIGNITION CONTROL 8I - 21
SPARK PLUG CABLE (Continued)

When replacing the spark plug and coil cables,
route the cables correctly and secure in the proper
retainers. Failure to route the cables properly can
cause the radio to reproduce ignition noise. It could
also cause cross ignition of the plugs or short circuit
the cables to ground.
When installing new cables, make sure a positive
connection is made. A snap should be felt when a
good connection is made between the plug cable and
the distributor cap tower.
Fig. 39 Spark Plug Cable OrderÐ8.0L V-10 Engine
8I - 22 IGNITION CONTROLBR/BE
SPARK PLUG CABLE (Continued)

INSTRUMENT CLUSTER
TABLE OF CONTENTS
page page
INSTRUMENT CLUSTER
DESCRIPTION..........................2
OPERATION............................3
DIAGNOSIS AND TESTING - INSTRUMENT
CLUSTER............................6
REMOVAL.............................10
DISASSEMBLY.........................10
ASSEMBLY............................12
INSTALLATION.........................13
ABS INDICATOR
DESCRIPTION.........................14
OPERATION...........................14
AIRBAG INDICATOR
DESCRIPTION.........................15
OPERATION...........................15
BRAKE/PARK BRAKE INDICATOR
DESCRIPTION.........................15
OPERATION...........................15
DIAGNOSIS AND TESTING - BRAKE
INDICATOR..........................16
CHECK GAUGES INDICATOR
DESCRIPTION.........................17
OPERATION...........................17
CRUISE INDICATOR
DESCRIPTION.........................18
OPERATION...........................18
ENGINE TEMPERATURE GAUGE
DESCRIPTION.........................18
OPERATION...........................19
FUEL GAUGE
DESCRIPTION.........................19
OPERATION...........................20
GEAR SELECTOR INDICATOR
DESCRIPTION.........................20
OPERATION...........................21
HIGH BEAM INDICATOR
DESCRIPTION.........................21
OPERATION...........................21
DIAGNOSIS AND TESTING - HIGH BEAM
INDICATOR..........................21
LOW FUEL INDICATOR
DESCRIPTION.........................22
OPERATION...........................22
MALFUNCTION INDICATOR LAMP MIL
DESCRIPTION.........................23
OPERATION...........................23
ODOMETER
DESCRIPTION.........................24
OPERATION...........................24OIL PRESSURE GAUGE
DESCRIPTION.........................25
OPERATION...........................25
OVERDRIVE OFF INDICATOR
DESCRIPTION.........................26
OPERATION...........................26
SEATBELT INDICATOR
DESCRIPTION.........................27
OPERATION...........................27
SERVICE REMINDER INDICATOR
DESCRIPTION.........................27
OPERATION...........................28
SHIFT INDICATOR (TRANSFER CASE)
DESCRIPTION.........................28
OPERATION...........................28
DIAGNOSIS AND TESTING - FOUR-WHEEL
DRIVE INDICATOR....................29
SPEEDOMETER
DESCRIPTION.........................29
OPERATION...........................30
TACHOMETER
DESCRIPTION.........................30
OPERATION...........................30
TRANS OVERTEMP INDICATOR
DESCRIPTION.........................31
OPERATION...........................31
TURN SIGNAL INDICATOR
DESCRIPTION.........................32
OPERATION...........................32
DIAGNOSIS AND TESTING - TURN SIGNAL
INDICATOR..........................32
UPSHIFT INDICATOR
DESCRIPTION.........................32
OPERATION...........................33
VOLTAGE GAUGE
DESCRIPTION.........................33
OPERATION...........................33
WAIT-TO-START INDICATOR
DESCRIPTION.........................34
OPERATION...........................34
WASHER FLUID INDICATOR
DESCRIPTION.........................35
OPERATION...........................35
DIAGNOSIS AND TESTING - WASHER FLUID
INDICATOR..........................35
WATER-IN-FUEL INDICATOR
DESCRIPTION.........................36
OPERATION...........................36
BR/BEINSTRUMENT CLUSTER 8J - 1

INSTRUMENT CLUSTER
DESCRIPTION
The instrument cluster for this model is an Elec-
troMechanical Instrument Cluster (EMIC) module
that is located in the instrument panel above the
steering column opening, directly in front of the
driver (Fig. 1). The EMIC gauges and indicators are
protected by an integral clear plastic cluster lens,
and are visible through a dedicated opening in the
cluster bezel on the instrument panel. Just behind
the cluster lens is the cluster hood. The cluster hood
serves as a visor and shields the face of the cluster
from ambient light and reflections to reduce glare.
Behind the cluster hood is the cluster overlay and
gauges. The overlay is a multi-layered unit. The
dark, visible surface of the outer layer of the overlay
is marked with all of the gauge identification and
graduations, but this layer is also translucent. The
darkness of this outer layer prevents the cluster from
appearing cluttered or busy by concealing the cluster
indicators that are not illuminated, while the trans-
lucence of this layer allows those indicators and icons
that are illuminated to be readily visible. The under-
lying layer of the overlay is opaque and allows light
from the various indicators and illumination lamps
behind it to be visible through the outer layer of the
overlay only through predetermined cutouts. On the
lower edge of the cluster lens just left of center, the
odometer/trip odometer switch knob protrudesthrough a dedicated hole in the lens. The remainder
of the EMIC, including the mounts and the electrical
connections, are concealed behind the cluster bezel.
The molded plastic EMIC housing has four integral
mounting tabs, two each on the upper and lower
edges of the housing. The EMIC is secured to the
molded plastic instrument panel cluster carrier with
four screws. All electrical connections to the EMIC
are made at the back of the cluster housing through
two take outs of the instrument panel wire harness,
each equipped with a self-docking connector.
A single EMIC module is offered on this model.
This module utilizes integrated circuitry and infor-
mation carried on the Chrysler Collision Detection
(CCD) data bus network for control of all gauges and
many of the indicators. (Refer to 8 - ELECTRICAL/
ELECTRONIC CONTROL MODULES/COMMUNI-
CATION - DESCRIPTION). The EMIC also uses
several hard wired inputs in order to perform its
many functions. In addition to instrumentation and
indicators, the EMIC has hardware and/or software
to support the following functions:
²Chime Warning Requests- The EMIC sends
chime tone requests over a hard wired circuit to the
Central Timer Module (CTM) when it monitors cer-
tain conditions or inputs. The CTM replaces the
chime or buzzer module and performs the functions
necessary to provide audible alerts that are synchro-
nized with the visual alerts provided by the EMIC.
(Refer to 8 - ELECTRICAL/CHIME/BUZZER -
DESCRIPTION).
²Vacuum Fluorescent Display (VFD) Dim-
ming Service- The EMIC performs the functions
necessary to eliminate the need for a separate VFD
dimming module by providing control and synchroni-
zation of the illumination intensity of all vacuum flu-
orescent displays in the vehicle, as well as a parade
mode.
The EMIC module incorporates a blue-green digital
VFD for displaying odometer and trip odometer infor-
mation, as well as the amber cruise-on indicator dis-
play function. Some variations of the EMIC are
necessary to support optional equipment and regula-
tory requirements. The EMIC includes the following
analog gauges:
²Coolant Temperature Gauge
²Fuel Gauge
²Oil Pressure Gauge
²Speedometer
²Tachometer
²Voltage Gauge
The EMIC also includes provisions for the follow-
ing indicators:
²Airbag Indicator
²Antilock Brake System (ABS) Indicator
²Brake Indicator
Fig. 1 Instrument Cluster Components
1 - COVER
2 - HOUSING
3 - MASK AND GAUGES
4 - HOOD
5 - LENS
6 - CIRCUIT BOARD
7 - ODOMETER RESET BUTTON
8J - 2 INSTRUMENT CLUSTERBR/BE

²Check Gauges Indicator
²Cruise Indicator (Odometer VFD)
²Four-Wheel Drive Indicator
²High Beam Indicator
²Low Fuel Indicator
²Washer Fluid Indicator
²Malfunction Indicator Lamp (MIL)
²Overdrive-Off Indicator
²Seatbelt Indicator
²Service Reminder Indicator (SRI)
²Transmission Overtemp Indicator
²Turn Signal (Right and Left) Indicators
²Upshift Indicator
²Wait-To-Start Indicator (Diesel Only)
²Water-In-Fuel Indicator (Diesel Only)
Some of these indicators are either programmable
or automatically configured when the EMIC is con-
nected to the vehicle electrical system. This feature
allows those indicators to be activated or deactivated
for compatibility with certain optional equipment.
The EMIC also includes a provision for mounting the
automatic transmission gear selector indicator in the
lower right corner of the cluster. The spring-loaded,
cable driven, mechanical gear selector indicator gives
an indication of the transmission gear that has been
selected with the automatic transmission gear selec-
tor lever. The gear selector indicator pointer is easily
visible through an opening provided in the front of
the cluster overlay, and is also lighted by the cluster
illumination lamps for visibility at night. Models
equipped with a manual transmission have a block-
out plate installed in place of the gear selector indi-
cator.
Cluster illumination is accomplished by adjustable
incandescent back lighting, which illuminates the
gauges for visibility when the exterior lighting is
turned on. The EMIC high beam indicator, turn sig-
nal indicators, and wait-to-start indicator are also
illuminated by dedicated incandescent bulbs. The
remaining indicators in the EMIC are each illumi-
nated by a dedicated Light Emitting Diode (LED)
that is soldered onto the electronic circuit board.
Each of the incandescent bulbs is secured by an inte-
gral bulb holder to the electronic circuit board from
the back of the cluster housing.
Hard wired circuitry connects the EMIC to the
electrical system of the vehicle. These hard wired cir-
cuits are integral to several wire harnesses, which
are routed throughout the vehicle and retained by
many different methods. These circuits may be con-
nected to each other, to the vehicle electrical system
and to the EMIC through the use of a combination of
soldered splices, splice block connectors, and many
different types of wire harness terminal connectors
and insulators. Refer to the appropriate wiring infor-
mation. The wiring information includes wiring dia-grams, proper wire and connector repair procedures,
further details on wire harness routing and reten-
tion, as well as pin-out and location views for the
various wire harness connectors, splices and grounds.
The EMIC modules for this model are serviced only
as complete units. The EMIC module cannot be
adjusted or repaired. If a gauge, an LED indicator,
the VFD, the electronic circuit board, the circuit
board hardware, the cluster overlay, or the EMIC
housing are damaged or faulty, the entire EMIC mod-
ule must be replaced. The cluster lens and hood unit,
the rear cluster housing cover, the automatic trans-
mission gear selector indicator, and the incandescent
lamp bulbs with holders are available for individual
service replacement.
OPERATION
The ElectroMechanical Instrument Cluster (EMIC)
is designed to allow the vehicle operator to monitor
the conditions of many of the vehicle components and
operating systems. The gauges and indicators in the
EMIC provide valuable information about the various
standard and optional powertrains, fuel and emis-
sions systems, cooling systems, lighting systems,
safety systems and many other convenience items.
The EMIC is installed in the instrument panel so
that all of these monitors can be easily viewed by the
vehicle operator when driving, while still allowing
relative ease of access for service. The microproces-
sor-based EMIC hardware and software uses various
inputs to control the gauges and indicators visible on
the face of the cluster. Some of these inputs are hard
wired, but most are in the form of electronic mes-
sages that are transmitted by other electronic mod-
ules over the Chrysler Collision Detection (CCD) data
bus network. (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/COMMUNICATION
- OPERATION).
The EMIC microprocessor smooths the input data
using algorithms to provide gauge readings that are
accurate, stable and responsive to operating condi-
tions. These algorithms are designed to provide
gauge readings during normal operation that are con-
sistent with customer expectations. However, when
abnormal conditions exist, such as low/high battery
voltage, low oil pressure, or high coolant tempera-
ture, the algorithm drives the gauge pointer to an
extreme position and the microprocessor turns on the
Check Gauges indicator to provide a distinct visual
indication of a problem to the vehicle operator. The
instrument cluster circuitry may also generate a
hard wired chime tone request to the Central Timer
Module (CTM) when it monitors certain conditions or
inputs, in order to provide the vehicle operator with
an audible alert.
BR/BEINSTRUMENT CLUSTER 8J - 3
INSTRUMENT CLUSTER (Continued)

The EMIC circuitry operates on battery current
received through a fused B(+) fuse in the Junction
Block (JB) on a non-switched fused B(+) circuit, and
on battery current received through a fused ignition
switch output (st-run) fuse in the JB on a fused igni-
tion switch output (st-run) circuit. This arrangement
allows the EMIC to provide some features regardless
of the ignition switch position, while other features
will operate only with the ignition switch in the Start
or On positions. The EMIC circuitry is grounded
through two separate ground circuits located in one
of the two instrument cluster connectors and take
outs of the instrument panel wire harness. One
ground circuit receives ground through a take out
with an eyelet terminal connector of the instrument
panel wire harness that is secured by a nut to a
ground stud located on the left instrument panel end
bracket, while the other ground circuit receives
ground through a take out with an eyelet terminal
connector of the instrument panel wire harness that
is secured by a nut to a ground stud located on the
back of the instrument panel armature above the
inboard side of the instrument panel steering column
opening.
The EMIC also has a self-diagnostic actuator test
capability, which will test each of the CCD bus mes-
sage-controlled functions of the cluster by lighting
the appropriate indicators and positioning the gauge
needles at several predetermined locations on the
gauge faces in a prescribed sequence. (Refer to 8 -
ELECTRICAL/INSTRUMENT CLUSTER - DIAGNO-
SIS AND TESTING). See the owner's manual in the
vehicle glove box for more information on the fea-
tures, use and operation of the EMIC.
GAUGES
All gauges receive battery current through the
EMIC circuitry when the ignition switch is in the On
or Start positions. With the ignition switch in the Off
position battery current is not supplied to any
gauges, and the EMIC circuitry is programmed to
move all of the gauge needles back to the low end of
their respective scales. Therefore, the gauges do not
accurately indicate any vehicle condition unless the
ignition switch is in the On or Start positions. All of
the EMIC gauges, except the odometer, are air core
magnetic units. Two fixed electromagnetic coils are
located within each gauge. These coils are wrapped
at right angles to each other around a movable per-
manent magnet. The movable magnet is suspended
within the coils on one end of a pivot shaft, while the
gauge needle is attached to the other end of the
shaft. One of the coils has a fixed current flowing
through it to maintain a constant magnetic field
strength. Current flow through the second coil
changes, which causes changes in its magnetic fieldstrength. The current flowing through the second coil
is changed by the EMIC circuitry in response to mes-
sages received over the CCD data bus. The gauge
needle moves as the movable permanent magnet
aligns itself to the changing magnetic fields created
around it by the electromagnets.
The gauges are diagnosed using the EMIC self-di-
agnostic actuator test. (Refer to 8 - ELECTRICAL/
INSTRUMENT CLUSTER - DIAGNOSIS AND
TESTING). Proper testing of the CCD data bus and
the data bus message inputs to the EMIC that con-
trol each gauge require the use of a DRBIIItscan
tool. Refer to the appropriate diagnostic information.
Specific operation details for each gauge may be
found elsewhere in this service manual.
VACUUM-FLUORESCENT DISPLAY
The Vacuum-Fluorescent Display (VFD) module is
soldered to the EMIC circuit board. The display is
active with the ignition switch in the On or Start
positions, and inactive when the ignition switch is in
any other position. The VFD has several display
capabilities including odometer, trip odometer, and
an amber ªCRUISEº indication whenever the
optional speed control system is turned On. The
cruise indicator function of the VFD is automatically
enabled or disabled by the EMIC circuitry based
upon whether the vehicle is equipped with the speed
control option. An odometer/trip odometer switch on
the EMIC circuit board is used to control several of
the display modes. This switch is actuated manually
by depressing the odometer/trip odometer switch
knob that extends through the lower edge of the clus-
ter lens, just right of center. Actuating this switch
momentarily with the ignition switch in the On posi-
tion will toggle the VFD between the odometer and
trip odometer modes. The word ªTRIPº will also
appear in blue-green text when the VFD trip odome-
ter mode is active. Depressing the switch button for
about two seconds while the VFD is in the trip odom-
eter mode will reset the trip odometer value to zero.
Holding this switch depressed while turning the igni-
tion switch from the Off position to the On position
will activate the EMIC self-diagnostic actuator test.
The EMIC will automatically flash the odometer or
trip odometer information on and off if there is a loss
of CCD data bus communication. The VFD will also
display various information used in several diagnos-
tic procedures. Refer to the appropriate diagnostic
information for additional details on this VFD func-
tion.
The VFD is diagnosed using the EMIC self-diag-
nostic actuator test. (Refer to 8 - ELECTRICAL/IN-
STRUMENT CLUSTER - DIAGNOSIS AND
TESTING). Proper testing of the CCD data bus and
the data bus message inputs to the EMIC that con-
8J - 4 INSTRUMENT CLUSTERBR/BE
INSTRUMENT CLUSTER (Continued)