fuse DODGE RAM 2003 Service Repair Manual

TRANSMISSION SOLENOID/TRS ASSEMBLY (3.7L/4.7L/5.7L) - BLACK 23 WAY
CAV CIRCUIT FUNCTION
1 L10 18BR/LG FUSED IGNITION SWITCH OUTPUT (RUN)
2 T120 18LG LR SOLENOID CONTROL
3 T24 18BR/YL TRS T41 SENSE
4 T41 18BK/WT (5.7L) TRS T41 SENSE
4 T24 20BR/YL (4.7L) TRS T41 SENSE
5 T42 18VT/WT TRS T42 SENSE
6 L1 18VT/BK BACK-UP LAMP FEED
7 T60 18BR OVERDRIVE SOLENOID CONTROL
8 T3 18VT TRS T3 SENSE
9 T1 18LG/BK TRS T1 SENSE
10 T16 16RD TRANSMISSION CONTROL RELAY OUTPUT
11 T48 18DB 4C PRESSURE SWITCH SENSE
12 T118 18YL/DB PRESSURE CONTROL SOLENOID CONTROL
13 T4 18PK/OR TRS T2 SENSE
14 T50 18DG LOW/REVERSE PRESSURE SWITCH SENSE
15 T147 18LB 2C PRESSURE SWITCH SENSE
16 T9 18OR/BK OVERDRIVE PRESSURE SWITCH SENSE
17 T59 18PK UNDERDRIVE SOLENOID CONTROL
18 T29 18GY UNDERDRIVE PRESSURE SWITCH SENSE
19 T159 18DG/WT 4C SOLENOID CONTROL
20 T119 18WT/DB 2C SOLENOID CONTROL
21 T140 18VT/LG PRESSURE CONTROL SOLENOID CONTROL
22 T13 18DB/BK (5.7L) SPEED SENSOR GROUND
22 K4 18BK/LB (4.7L) SENSOR GROUND
23 T54 18VT TRANSMISSION TEMPERATURE SENSOR SIGNAL
UNDERHOOD LAMP - BLACK 2 WAY
CAV CIRCUIT FUNCTION
1 Z235 20LB/BK GROUND
2 M1 18PK FUSED B(+)
VACUUM PUMP (DIESEL)-4WAY
CAV CIRCUIT FUNCTION
1- -
2 Y135 18LG/BK FUSED IGNITION SWITCH OUTPUT (RUN-START)
3- -
4 Z11 18BK/WT GROUND
8W - 80 - 106 8W-80 CONNECTOR PIN-OUTSDR

VEHICLE SPEED SENSOR (DIESEL)-3WAY
CAV CIRCUIT FUNCTION
1 K6 18VT/WT 5 VOLT SUPPLY
2 K167 18BR/TL ACCELERATOR PEDAL POSITION SENSOR GROUND
NO. 1
3 G17 18WT/TN SPEEDOMETER SIGNAL
VISTRONIC FAN DRIVE (DIESEL)-6WAY
CAV CIRCUIT FUNCTION
1 Y1 18LG PARK LOCKOUT SOLENOID CONTROL
2 K4 18BK/LB SENSOR GROUND
3 Y5 18OR FAN SPEED
4- -
5 Y3 18WT SENSOR SUPPLY
6 F15 20DB FUSED IGNTION SWITCH OUTPUT (RUN)
WASHER FLUID LEVEL SWITCH - BLACK 2 WAY
CAV CIRCUIT FUNCTION
1 Y137 20VT/LB EXCEPT 8.0L/DIESEL SENSOR GROUND
2 G29 20BK/TN WASHER FLUID SWITCH SENSE
2 Y137 20VT/LB 8.0L/DIESEL SENSOR GROUND
WASHER PUMP MOTOR-FRONT - BLACK 2 WAY
CAV CIRCUIT FUNCTION
1 Z216 20BK/VT GROUND
2 V10 20BR WASHER PUMP MOTOR CONTROL
WATER IN FUEL SENSOR (DIESEL)-2WAY
CAV CIRCUIT FUNCTION
1 K104 18RD/WT SENSOR GROUND
2 G20 18VT/YL IGNITION SWITCH SENSE
DR8W-80 CONNECTOR PIN-OUTS 8W - 80 - 107

8W-97 POWER DISTRIBUTION
TABLE OF CONTENTS
page page
POWER DISTRIBUTION
DESCRIPTION..........................1
OPERATION............................1
SPECIAL TOOLS
POWER DISTRIBUTION SYSTEMS.........2
CIGAR LIGHTER OUTLET
DESCRIPTION..........................2
OPERATION............................2
DIAGNOSIS AND TESTING - CIGAR LIGHTER
OUTLET.............................2
INTEGRATED POWER MODULE
DESCRIPTION..........................3
OPERATION............................3
REMOVAL.............................3
INSTALLATION..........................4
FRONT CONTROL MODULE
DESCRIPTION..........................4
OPERATION............................5
DIAGNOSIS AND TESTING - FRONT
CONTROL MODULE....................5
REMOVAL.............................5
INSTALLATION..........................5
IOD FUSE
DESCRIPTION..........................6OPERATION............................6
REMOVAL.............................6
INSTALLATION..........................7
POWER OUTLET
DESCRIPTION..........................7
OPERATION............................7
DIAGNOSIS AND TESTING - POWER OUTLET . 7
REMOVAL.............................7
INSTALLATION..........................7
RELAY
DESCRIPTION..........................8
OPERATION............................8
DIAGNOSIS AND TESTING - RELAY.........8
REMOVAL.............................9
INSTALLATION..........................9
MICRO RELAY
DESCRIPTION..........................9
OPERATION............................9
DIAGNOSIS AND TESTING - MICRO-RELAY . . . 9
REMOVAL.............................10
INSTALLATION.........................10
POWER DISTRIBUTION
DESCRIPTION
This group covers the various standard and
optional power distribution components used on this
model. The power distribution system for this vehicle
consists of the following components:
²Integrated Power Module (IPM)
²Front Control Module (FCM)
²Power Distribution Center (PDC)
²Power Outlets
²Cigar Lighter Outlets
²Relays
Refer to Wiring Diagrams for complete circuit sche-
matics.
The power distribution system also incorporates
various types of circuit control and protection fea-
tures, including:
²Automatic resetting circuit breakers
²Blade-type fuses
²Cartridge fuses
²RelaysFollowing are general descriptions of the major
components in the power distribution system. See the
owner's manual in the vehicle glove box for more
information on the features and use of all of the
power distribution system components.
OPERATION
The power distribution system for this vehicle is
designed to provide safe, reliable, and centralized dis-
tribution points for the electrical current required to
operate all of the many standard and optional facto-
ry-installed electrical and electronic powertrain,
chassis, safety, security, comfort and convenience sys-
tems. At the same time, the power distribution sys-
tem was designed to provide ready access to these
electrical distribution points for the vehicle techni-
cian to use when conducting diagnosis and repair of
faulty circuits. The power distribution system can
also prove useful for the sourcing of additional elec-
trical circuits that may be required to provide the
electrical current needed to operate many accessories
that the vehicle owner may choose to have installed
in the aftermarket.
DR8W-97 POWER DISTRIBUTION 8W - 97 - 1

SPECIAL TOOLS
POWER DISTRIBUTION SYSTEMS
CIGAR LIGHTER OUTLET
DESCRIPTION
On models equipped a cigar lighter outlet is
installed to the left of the center stack area in the
lower instrument panel. The cigar lighter outlet is
secured by a snap fit within the bezel.
The cigar lighter outlet, plastic cap and the knob
and heating element unit are available for service
replacement. These components cannot be repaired
and, if faulty or damaged, they must be replaced.
OPERATION
The cigar lighter consists of two major components:
a knob and heating element unit, and the cigar
lighter base or outlet shell. The receptacle shell is
connected to ground, and an insulated contact in the
bottom of the shell is connected to battery current.
The cigar lighter receives battery voltage from a fuse
in the junction block when the ignition switch is in
the Accessory or Run positions.
The cigar lighter knob and heating element are
encased within a spring-loaded housing, which also
features a sliding protective heat shield. When the
knob and heating element are inserted in the outlet
shell, the heating element resistor coil is grounded
through its housing to the outlet shell. If the cigar
lighter knob is pushed inward, the heat shield slides
up toward the knob exposing the heating element,
and the heating element extends from the housing
toward the insulated contact in the bottom of the
outlet shell.
Two small spring-clip retainers are located on
either side of the insulated contact inside the bottom
of the outlet shell. These clips engage and hold the
heating element against the insulated contact longenough for the resistor coil to heat up. When the
heating element is engaged with the contact, battery
current can flow through the resistor coil to ground,
causing the resistor coil to heat.
When the resistor coil becomes sufficiently heated,
excess heat radiates from the heating element caus-
ing the spring-clips to expand. Once the spring-clips
expand far enough to release the heating element,
the spring-loaded housing forces the knob and heat-
ing element to pop back outward to their relaxed
position. When the cigar lighter knob and element
are pulled out of the outlet shell, the protective heat
shield slides downward on the housing so that the
heating element is recessed and shielded around its
circumference for safety.
DIAGNOSIS AND TESTING - CIGAR LIGHTER
OUTLET
For complete circuit diagrams, refer toWiring
Diagrams.
(1) Check the fused B(+) fuse in the integrated
power module. If OK, go to Step 2. If not OK, repair
the shorted circuit or component as required and
replace the faulty fuse.
(2) Turn the ignition switch to the Run position.
Check for battery voltage at the fused B(+) fuse in
the integrated power module. If OK, go to Step 3. If
not OK, repair the open or short as required.
(3) Remove the cigar lighter knob and element
from the cigar lighter outlet shell. Check for continu-
ity between the inside circumference of the cigar
lighter outlet shell and a good ground. there should
be continuity. If OK, go to Step 4. If not OK, go to
Step 5.
(4) Turn the ignition switch to the Run position.
Check for battery voltage at the insulated contact
located at the back of the cigar lighter outlet shell. If
OK, replace the faulty cigar lighter knob and ele-
ment. If not OK, go to Step 5.
(5) Turn the ignition switch to the Off position.
Disconnect and isolate the battery negative cable.
Check for continuity between the ground circuit cav-
ity of the cigar lighter 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. Turn the
ignition switch to the Accessory or Run positions.
Check for battery voltage at the fused B(+) circuit
cavity of the cigar lighter wire harness connector. If
OK, replace the faulty cigar lighter outlet. If not OK,
repair the open fused B(+) circuit to the integrated
power module fuse as required.Terminal Pick Kit 6680
8W - 97 - 2 8W-97 POWER DISTRIBUTIONDR
POWER DISTRIBUTION (Continued)

INTEGRATED POWER MODULE
DESCRIPTION
The Integrated Power Module (IPM) (Fig. 1) is a
combination of the Power Distribution Center (PDC)
and the Front Control Module (FCM). The IPM is
located in the engine compartment, next to the bat-
tery on this model. The power distribution center
mates directly with the Front Control Module (FCM)
to form the Integrated Power Module Fuse and Relay
Center. The power distribution center (PDC) is a
printed circuit board based module that contains
fuses and relays, while the front control module con-
tains the electronics controlling the integrated power
module and other functions. This integrated power
module connects directly to the battery positive via a
stud located on top of the unit. The ground connec-
tion is via electrical connectors. The integrated power
module provides the primary means of voltage distri-
bution and protection for the entire vehicle.
The molded plastic integrated power module hous-
ing includes a base and cover. The integrated power
module cover is easily opened or removed for service
access by unscrewing the cover retaining nut and has
a fuse and relay layout map integral to the inside
surface of the cover. This integrated power module
housing base and cover are secured in place via bolts
to the left front fender support assembly.
Replaceable components of the integrated power
module assembly are broken down into the followingcomponents: the Power Distribution Center (PDC),
the integrated power module cover, the Front Control
Module (FCM) and the Integrated Power Module
Assembly which includes the power distribution cen-
ter, the cover and FCM.Refer to the Front Con-
trol Module in the Electronic Control Module
sectionof this service manual for information on the
front control module.
OPERATION
All of the current from the battery and the gener-
ator output enters the integrated power module via a
stud on the top of the module. The integrated power
module cover is removed to access the fuses or relays.
Internal connections of all of the power distribution
center circuits is accomplished by a combination of
bus bars and a printed circuit board. Refer to the
Wiring section of the service manual for complete
integrated power module circuit schematics.
REMOVAL
(1) Disconnect the negative and positive battery
cables.
(2) Unsnap cover and remove the B+ terminal nut
from the integrated power module B+ terminal.
Remove the B+ cable from the integrated power mod-
ule.
(3) Disconnect the gray connector from the inte-
grated power module.
Fig. 1 DR INTEGRATED POWER MODULE
1 - POWER DISTRIBUTION CENTER HOUSING
2 - FRONT CONTROL MODULE ELECTRICAL CONNECTOR
Fig. 2 DR INTEGRATED POWER MODULE
1 - COVER RETAINING BOLT
2 - INTEGRATED POWER MODULE RETAINING BOLT
3 - RETAINING SCREW
4 - INTEGRATED POWER MODULE COVER
DR8W-97 POWER DISTRIBUTION 8W - 97 - 3

IOD FUSE
DESCRIPTION
All vehicles are equipped with an Ignition-Off
Draw (IOD) fuse that is disconnected within the Inte-
grated Power Module when the vehicle is shipped
from the factory. Dealer personnel are to reconnect
the IOD fuse in the Integrated Power Module as part
of the preparation procedures performed just prior to
new vehicle delivery.
A laser printed fuse layout map is integral to the
Integrated Power Module cover to ensure proper fuse
identification. The IOD fuse is a 20 ampere mini
blade-type fuse, located in fuse cavity # 51 (Fig. 6).
The fuse is secured within a black molded plastic
fuse holder and puller unit that serves both as a tool
for disconnecting and reconnecting the fuse in its
Integrated Power Module cavity, and as a fuse holder
that conveniently stores the fuse in the same Inte-
grated Power Module cavity after it has been discon-
nected.
CIRCUITS INCLUDED WITH IOD FUSE
²Cluster (CCN)
²Diagnostic Connector
²Map Lamps
²Glove Box Lamp
²Courtesy Lamps
²Radio
²Underhood Lamp
OPERATION
The term ignition-off draw identifies a normal con-
dition where power is being drained from the battery
with the ignition switch in the Off position. The IOD
fuse feeds the memory and sleep mode functions for
some of the electronic modules in the vehicle as well
as various other accessories that require battery cur-
rent when the ignition switch is in the Off position.
The only reason the IOD fuse is disconnected is to
reduce the normal IOD of the vehicle electrical sys-
tem during new vehicle transportation and pre-deliv-
ery storage to reduce battery depletion, while still
allowing vehicle operation so that the vehicle can be
loaded, unloaded and moved as needed by both vehi-
cle transportation company and dealer personnel.
The IOD fuse is disconnected from Integrated
Power Module fuse cavity # 51 when the vehicle is
shipped from the assembly plant. Dealer personnel
must reconnect the IOD fuse when the vehicle is
being prepared for delivery in order to restore full
electrical system operation. Once the vehicle is pre-
pared for delivery, the IOD function of this fuse
becomes transparent and the fuse that has been
assigned the IOD designation becomes only another
Fused B(+) circuit fuse.
The IOD fuse can be used by the vehicle owner as
a convenient means of reducing battery depletion
when a vehicle is to be stored for periods not to
exceed about thirty days. However, it must be
remembered that disconnecting the IOD fuse will not
eliminate IOD, but only reduce this normal condition.
If a vehicle will be stored for more than about thirty
days, the battery negative cable should be discon-
nected to eliminate normal IOD; and, the battery
should be tested and recharged at regular intervals
during the vehicle storage period to prevent the bat-
tery from becoming discharged or damaged.
REMOVAL
The Ignition-Off Draw (IOD) fuse is disconnected
from Integrated Power Module fuse cavity # 51 when
the vehicle is shipped from the assembly plant.
Dealer personnel must reconnect the IOD fuse when
the vehicle is being prepared for delivery in order to
restore full electrical system operation.
(1) Turn the ignition switch to the Off position.
(2) Remove the Integrated Power Module cover.
(3) Grasp the outer tabs of the IOD fuse holder
unit in fuse cavity # 51 between the thumb and fore-
finger and pull the unit firmly upward.
(4) Install the Integrated Power Module cover.
Fig. 6 IOD FUSE LOCATION
1 - IOD FUSE
8W - 97 - 6 8W-97 POWER DISTRIBUTIONDR

INSTALLATION
(1) Turn the ignition switch to the Off position.
(2) Remove the Integrated Power Module cover.
(3) To install the IOD fuse, use a thumb to press
the IOD fuse holder unit in fuse cavity # 51 firmly
into the Integrated Power Module.
(4) Install the Integrated Power Module cover.
POWER OUTLET
DESCRIPTION
Two power outlets are utilized on this model. One
in the instrument panel center lower bezel and the
other in the center console. The power outlet bases
are secured by a snap fit within the instrument
panel or trim 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 out-
let 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 integrated power module 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 AND TESTING - POWER OUTLET
For complete circuit diagrams, refer toWiring
Diagrams.
(1) Check the fused B(+) fuse in the integrated
power module. 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 integrated power module. 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 for
continuity 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 integrated power
module 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.
(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 panel (Fig. 7).
(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.
(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) Reconnect the instrument panel wire harness
connector to the cigar lighter or power outlet recep-
tacle base connector receptacle.
(2) Install the cigar lighter or power outlet mount
into the instrument panel.
(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.
DR8W-97 POWER DISTRIBUTION 8W - 97 - 7
IOD FUSE (Continued)

(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.
RELAY
DESCRIPTION
A relay (Fig. 8) is an electromechanical device that
switches fused battery current to a electrical compo-
nent when the ignition switch is turned to the Acces-
sory or Run positions, or when controlled by a
electronic module. The relays are located in the inte-
grated power module.
The relay is a International Standards Organiza-
tion (ISO) relay. Relays conforming to the ISO speci-
fications have common physical dimensions, current
capacities, terminal patterns, and terminal functions.
A relay cannot be repaired or adjusted and, if
faulty or damaged, it must be replaced.
OPERATION
The ISO relay consists of an electromagnetic coil, a
resistor and three (two fixed and one movable) elec-
trical contacts. The movable (common feed) relay con-
tact is held against one of the fixed contacts
(normally closed) by spring pressure. When the elec-
tromagnetic coil is energized, it draws the movable
contact away from the normally closed fixed contact,
and holds it against the other (normally open) fixed
contact.
When the electromagnetic coil is de-energized,
spring pressure returns the movable contact to the
normally closed position. The resistor is connected in
parallel with the electromagnetic coil in the relay,
and helps to dissipate voltage spikes that are pro-
duced when the coil is de-energized.
DIAGNOSIS AND TESTING - RELAY
The relays are located in the integrated power
module. For complete circuit diagrams, refer toWir-
ing Diagrams.
(1) Remove the relay from its mounting location.
(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 60.7 - 80.3 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, perform the Relay Circuit Test that
follows. If not OK, replace the faulty relay.
Fig. 7 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
Fig. 8 ISO Relay
30 COMMON FEED
85 COIL GROUND
86 COIL BATTERY
87 NORMALLY OPEN
87A NORMALLY CLOSED
8W - 97 - 8 8W-97 POWER DISTRIBUTIONDR
POWER OUTLET (Continued)

DIAGNOSIS & TESTING - RELAY CIRCUIT TEST
(1) The relay common feed terminal cavity (30) of
the integrated power module is connected to battery
voltage and should be hot at all times. Check for bat-
tery voltage at the fused B(+) circuit cavity in the
integrated power module receptacle for the relay. If
OK, go to Step 2. If not OK, repair the fused B(+) cir-
cuit to the integrated power module fuse as required.
(2) The relay normally closed terminal (87A) is
connected to terminal 30 in the de-energized position,
but is not used for this application. Go to Step 3.
(3) The relay normally open terminal (87) is con-
nected to the common feed terminal (30) in the ener-
gized position. This terminal supplies battery voltage
to the fused B(+) fuse in the integrated power module
that feeds the accessory when the relay is energized
by the ignition switch. There should be continuity
between the integrated power module cavity for relay
terminal 87 and the fused B(+) fuse in the integrated
power module at all times. If OK, go to Step 4. If not
OK, repair the open fused B(+) circuit to the inte-
grated power module fuse as required.
(4) The coil ground terminal (85) is connected to
the electromagnet in the relay. It receives battery
feed to energize the relay when the ignition switch is
in the Accessory or Run positions. Turn the ignition
switch to the On position. Check for battery voltage
at the fused ignition switch output (acc/run) circuit
cavity for relay terminal 85 in the integrated power
module receptacle for the relay. If OK, go to Step 5. If
not OK, repair the open fused ignition switch output
(acc/run) circuit to the ignition switch as required.
(5) The coil battery terminal (86) is connected to
the electromagnet in the relay. The integrated power
module cavity for this terminal should have continu-
ity to ground at all times. If not OK, repair the open
ground circuit to ground as required.
REMOVAL
(1) Disconnect and isolate the negative battery
cable.
(2) Remove the relay by grasping it firmly and
pulling it straight out from its receptacle. A slight
back and fourth rocking motion may help the
removal process.
INSTALLATION
(1) Position the relay to the proper receptacle.
(2) Align the relay terminals with the terminal
cavities in the receptacle.
(3) Push firmly and evenly on the top of the relay
until the terminals are fully seated in the terminal
cavities in the receptacle.
(4) Connect the negative battery cable.
MICRO RELAY
DESCRIPTION
A micro-relay is a conventional International Stan-
dards Organization (ISO) micro relay (Fig. 9). Relays
conforming to the ISO specifications have common
physical dimensions, current capacities, terminal pat-
terns, and terminal functions. The relay is contained
within a small, rectangular, molded plastic housing
and is connected to all of the required inputs and
outputs by five integral male spade-type terminals
that extend from the bottom of the relay base.
Relays cannot be adjusted or repaired and, if faulty
or damaged, the unit must be replaced.
OPERATION
A micro-relay is an electromechanical switch that
uses a low current input from one source to control a
high current output to another device. The movable
common feed contact point is held against the fixed
normally closed contact point by spring pressure.
When the relay coil is energized, an electromagnetic
field is produced by the coil windings. This electro-
magnetic field draws the movable relay contact point
away from the fixed normally closed contact point,
and holds it against the fixed normally open contact
point. When the relay coil is de-energized, spring
pressure returns the movable contact point back
against the fixed normally closed contact point. A
resistor is connected in parallel with the relay coil in
the relay, and helps to dissipate voltage spikes and
electromagnetic interference that can be generated as
the electromagnetic field of the relay coil collapses.
DIAGNOSIS AND TESTING - MICRO-RELAY
(1) Remove the relay from its mounting location.
(2) A relay in the de-energized position should
have continuity between terminals 87A and 30, and
Fig. 9 DR ISO Micro Relay
30 - COMMON FEED
85 - COIL GROUND
86 - COIL BATTERY
87 - NORMALLY OPEN
87A - NORMALLY CLOSED
DR8W-97 POWER DISTRIBUTION 8W - 97 - 9
RELAY (Continued)

EXCESSIVE BLACK SMOKE
POSSIBLE CAUSE CORRECTION
Manifold Air Pressure (Boost) Sensor or sensor circuit
malfunctioning.A DTC should have been set. Refer to Powertrain
Diagnostic Procedures Information.
Raw fuel in intake manifold. Fuel injectors leaking on engine shutdown. Do Fuel
Injector Test (Refer to 14 - FUEL SYSTEM/FUEL
INJECTION/FUEL INJECTOR - DIAGNOSIS AND
TESTING).
Turbocharger air intake restriction. Remove restriction.
Turbocharger damaged. (Refer to 11 - EXHAUST SYSTEM/TURBOCHARGER
SYSTEM/TURBOCHARGER - INSPECTION).
Turbocharger has excess build up on compressor
wheel and/or diffuser vanes.(Refer to 11 - EXHAUST SYSTEM/TURBOCHARGER
SYSTEM/TURBOCHARGER - CLEANING).
Turbocharger wheel clearance out of specification. (Refer to 11 - EXHAUST SYSTEM/TURBOCHARGER
SYSTEM/TURBOCHARGER - INSPECTION).
EXCESSIVE WHITE SMOKE
POSSIBLE CAUSE CORRECTION
Air in fuel supply: Possible leak in fuel supply side
(between transfer pump and fuel tank module).(Refer to 14 - FUEL SYSTEM/FUEL DELIVERY/FUEL
TRANSFER PUMP - DIAGNOSIS AND TESTING).
Coolant leaking into combustion chamber. Do pressure test of cooling system (Refer to 7 -
COOLING - DIAGNOSIS AND TESTING).
Diagnostic Trouble Codes (DTC's) active or multiple,
intermittent DTC's.Refer to Powertrain Diagnostic Procedures Information.
In very cold ambient temperatures, engine block heater
is malfunctioning (if equipped).(Refer to 7 - COOLING/ENGINE/ENGINE BLOCK
HEATER - REMOVAL).
Engine coolant temperature sensor malfunctioning. A DTC should have been set. Refer to Powertrain
Diagnostic Procedures Information. Also check
thermostat operation (Refer to 7 - COOLING/ENGINE/
ENGINE COOLANT THERMOSTAT - DIAGNOSIS AND
TESTING).
Engine Control Module (ECM) not calibrated or has
incorrect calibration.A DTC should have been set. Refer to Powertrain
Diagnostic Procedures Information.
Fuel filter plugged. Refer to Powertrain Diagnostic Manual for fuel system
testing.
Fuel grade not correct or fuel quality is poor. Temporarily change fuel brands and note condition.
Change brand if necessary.
Fuel heater element or fuel heater temperature sensor
malfunctioning. This will cause wax type build-up in fuel
filter.Refer to Fuel Heater Testing (Refer to 14 - FUEL
SYSTEM/FUEL DELIVERY/FUEL HEATER -
DIAGNOSIS AND TESTING).
Fuel injector malfunctioning. A DTC should have been set. Perform9Cylinder cutout
Test9using DRB scan tool to isolate individual
cylinders. Also refer to Powertrain Diagnostic
Procedures Information and, (Refer to 14 - FUEL
SYSTEM/FUEL INJECTION/FUEL INJECTOR -
DIAGNOSIS AND TESTING).
Fuel injector hold-downs loose. Torque to specifications.
9 - 286 ENGINE 5.9L DIESELDR
ENGINE 5.9L DIESEL (Continued)