Dodge Durango (DN). Manual — part 267

STARTING SYSTEMS

TABLE OF CONTENTS

page

page

DESCRIPTION AND OPERATION

STARTING SYSTEM . . . . . . . . . . . . . . . . . . . . . . . 1
STARTER MOTOR. . . . . . . . . . . . . . . . . . . . . . . . . 2
STARTER RELAY . . . . . . . . . . . . . . . . . . . . . . . . . 3

DIAGNOSIS AND TESTING

STARTING SYSTEM . . . . . . . . . . . . . . . . . . . . . . . 3
STARTER MOTOR. . . . . . . . . . . . . . . . . . . . . . . . . 7

STARTER RELAY . . . . . . . . . . . . . . . . . . . . . . . . . 8

REMOVAL AND INSTALLATION

STARTER MOTOR. . . . . . . . . . . . . . . . . . . . . . . . . 9
STARTER RELAY . . . . . . . . . . . . . . . . . . . . . . . . 11

SPECIFICATIONS

STARTING SYSTEM . . . . . . . . . . . . . . . . . . . . . . 12

DESCRIPTION AND OPERATION

STARTING SYSTEM

DESCRIPTION

An electrically operated engine starting system is

standard factory-installed equipment on this model.
The starting system is designed to provide the vehi-
cle operator with a convenient, efficient and reliable
means of cranking and starting the internal combus-
tion engine used to power the vehicle and all of its
accessory systems from within the safe and secure
confines of the passenger compartment. See the own-
er’s manual in the vehicle glove box for more infor-
mation and instructions on the recommended use
and operation of the factory-installed starting sys-
tem.

The starting system consists of the following com-

ponents:

• Battery

• Starter relay

• Starter motor (including an integral starter sole-

noid)

• Ignition switch

• Park/neutral position switch

• Wire harnesses and connections (including the

battery cables).

This group provides complete service information

for the starter motor and the starter relay. Complete
service information for the other starting system
components can be located as follows:

• Refer to Battery in the proper section of Group

8A - Battery for complete service information for the
battery.

• Refer to Ignition Switch and Key Lock Cyl-

inder in the proper section of Group 8D - Ignition
System for complete service information for the igni-
tion switch.

• Refer to Park/Neutral Position Switch in the

proper section of Group 21 - Transmission for com-
plete service information for the park/neutral posi-
tion switch.

• Refer to the proper section of Group 8W - Wir-

ing Diagrams for complete service information and
circuit diagrams for the starting system wiring com-
ponents.

Group 8A covers the Battery, Group 8B covers the

Starting Systems, and Group 8C covers the Charging
System. We have separated these systems to make it
easier to locate the information you are seeking
within this Service Manual. However, when attempt-
ing to diagnose any of these systems, it is important
that you keep their interdependency in mind.

The battery, starting, and charging systems in the

vehicle operate with one another, and must be tested
as a complete system. In order for the vehicle to start
and charge properly, all of the components that are
used in these systems must perform within specifica-
tions.

The diagnostic procedures used in each of these

groups include the most basic conventional diagnostic
methods, to the more sophisticated On-Board Diag-
nostics (OBD) built into the Powertrain Control Mod-
ule (PCM). Use of an induction-type milliampere
ammeter, volt/ohmmeter, battery charger, carbon pile
rheostat (load tester), and 12-volt test lamp may be
required.

All OBD-sensed systems are monitored by the

PCM. Each monitored circuit is assigned a Diagnos-
tic Trouble Code (DTC). The PCM will store a DTC in
electronic memory for any failure it detects. Refer to
On-Board Diagnostic Test For Charging System
in the Diagnosis and Testing section of Group 8C -
Charging System for more information.

DN

STARTING SYSTEMS

8B - 1

OPERATION

The starting system components form two separate

circuits. A high-amperage feed circuit that feeds the
starter motor between 150 and 350 amperes, and a
low-amperage control circuit that operates on less
than 20 amperes. The high-amperage feed circuit
components include the battery, the battery cables,
the contact disc portion of the starter solenoid, and
the starter motor. The low-amperage control circuit
components include the ignition switch, the park/
neutral position switch, the starter relay, the electro-
magnetic windings of the starter solenoid, and the
connecting wire harness components.

Battery voltage is supplied through the low-amper-

age control circuit to the coil battery terminal of the
starter relay when the ignition switch is turned to
the momentary Start position. The park/neutral posi-
tion switch is installed in series between the starter
relay coil ground terminal and ground. This normally
open switch prevents starter motor operation unless
the automatic transmission gear selector is in the
Neutral or Park positions.

When the starter relay coil is energized, the nor-

mally open relay contacts close. The relay contacts
connect the relay common feed terminal to the relay
normally open terminal. The closed relay contacts
energize the starter solenoid coil windings.

The energized solenoid pull-in coil pulls in the sole-

noid plunger. The solenoid plunger pulls the shift
lever in the starter motor. This engages the starter
overrunning clutch and pinion gear with the starter
ring gear on the automatic transmission torque con-
verter or torque converter drive plate.

As the solenoid plunger reaches the end of its

travel, the solenoid contact disc completes the high-
amperage starter feed circuit and energizes the sole-
noid plunger hold-in coil. Current now flows between
the solenoid battery terminal and the starter motor,
energizing the starter.

Once the engine starts, the overrunning clutch pro-

tects the starter motor from damage by allowing the
starter pinion gear to spin faster than the pinion
shaft. When the driver releases the ignition switch to
the On position, the starter relay coil is de-energized.
This causes the relay contacts to open. When the
relay contacts open, the starter solenoid plunger
hold-in coil is de-energized.

When the solenoid plunger hold-in coil is de-ener-

gized, the solenoid plunger return spring returns the
plunger to its relaxed position. This causes the con-
tact disc to open the starter feed circuit, and the shift
lever to disengage the overrunning clutch and pinion
gear from the starter ring gear.

Following are general descriptions of the major

components in the starting system.

STARTER MOTOR

DESCRIPTION

The starter motors used for the 4.7L engines are

not interchangeable with the starter motors used for
the other available engines for this model. The
starter motors used for all 5.2L and 5.9L engines
available in this model are interchangeable.

The 4.7L engine starter motor is mounted with two

screws to the automatic transmission torque con-
verter housing on the left side of the engine. The
starter motors for all of the remaining engines are
mounted with one screw, a stud and a nut to the
automatic transmission torque converter housing and
are also located on the left side of the engine.

Each of these starter motors incorporates several

of the same features to create a reliable, efficient,
compact, lightweight and powerful unit. The electric
motors of both starters have four brushes contacting
the motor commutator. These starter motors use four
electromagnetic field coils wound around four pole
shoes. The starter motors are rated at 1.4 kilowatts
(about 1.9 horsepower) output at 12 volts.

These starter motors are serviced only as a unit

with their starter solenoids, and cannot be repaired.
If either component is faulty or damaged, the entire
starter motor and starter solenoid unit must be
replaced.

OPERATION

These starter motors are equipped with a gear

reduction (intermediate transmission) system. The
gear reduction system consists of a gear that is inte-
gral to the output end of the electric motor armature
shaft that is in continual engagement with a larger
gear that is splined to the input end of the starter
pinion gear shaft. This feature makes it possible to
reduce the dimensions of the starter. At the same
time, it allows higher armature rotational speed and
delivers increased torque through the starter pinion
gear to the starter ring gear.

The starter motors for all engines are activated by

an integral heavy duty starter solenoid switch
mounted to the overrunning clutch housing. This
electromechanical switch connects and disconnects
the feed of battery voltage to the starter motor and
actuates a shift fork that engages and disengages the
starter pinion gear with the starter ring gear.

These starter motors use an overrunning clutch

and starter pinion gear unit to engage and drive a
starter ring gear that is integral to the torque con-
verter or torque converter drive plate mounted on the
rear crankshaft flange.

8B - 2

STARTING SYSTEMS

DN

DESCRIPTION AND OPERATION (Continued)

STARTER RELAY

DESCRIPTION

The starter relay is an electromechanical device

that switches battery current to the pull-in coil of the
starter solenoid when the ignition switch is turned to
the Start position. The starter relay is located in the
Power Distribution Center (PDC), in the engine com-
partment. See the fuse and relay layout label affixed
to the inside surface of the PDC cover for starter
relay identification and location.

The starter relay is a International Standards

Organization (ISO) micro-relay. Relays conforming to
the ISO specifications have common physical dimen-
sions, current capacities, terminal patterns, and ter-
minal

functions.

The

ISO

micro-relay

terminal

functions are the same as a conventional ISO relay.
However, the ISO micro-relay terminal pattern (or
footprint) is different, the current capacity is lower,
and the physical dimensions are smaller than those
of the conventional ISO relay.

The starter 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 or diode, and three (two fixed and one mov-
able) electrical contacts. The movable (common feed)
relay contact 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 or diode is con-

nected in parallel with the electromagnetic coil in the
relay, and helps to dissipate voltage spikes that are
produced when the coil is de-energized.

DIAGNOSIS AND TESTING

STARTING SYSTEM

DIAGNOSIS

The battery, starting, and charging systems oper-

ate with one another, and must be tested as a com-
plete system. In order for the vehicle to start and
charge properly, all of the components involved in
these systems must perform within specifications.

Group 8A covers the Battery, Group 8B covers the

Starting Systems, and Group 8C covers the Charging
System. We have separated these systems to make it
easier to locate the information you are seeking
within this Service Manual. However, when attempt-
ing to diagnose any of these systems, it is important
that you keep their interdependency in mind.

The diagnostic procedures used in these groups

include the most basic conventional diagnostic meth-
ods, to the more sophisticated On-Board Diagnostics
(OBD) built into the Powertrain Control Module
(PCM). Use of an induction-type milliampere amme-
ter, volt/ohmmeter, battery charger, carbon pile rheo-
stat (load tester), and 12-volt test lamp may be
required.

All OBD-sensed systems are monitored by the

PCM. Each monitored circuit is assigned a Diagnos-
tic Trouble Code (DTC). The PCM will store a DTC in
electronic memory for any failure it detects. Refer to
On-Board Diagnostic Test For Charging System
in the Diagnosis and Testing section of Group 8C -
Charging System for more information.

DN

STARTING SYSTEMS

8B - 3

DESCRIPTION AND OPERATION (Continued)

Starting System Diagnosis

CONDITION

POSSIBLE CAUSE

CORRECTION

STARTER FAILS TO
OPERATE.

1. Battery discharged or
faulty.
2. Starting circuit wiring
faulty.
3. Starter relay faulty.
4. Ignition switch faulty.
5. Park/Neutral position
switch faulty or
misadjusted.
6. Starter solenoid faulty.
7. Starter motor faulty.

1. Refer to Battery in the Diagnosis and Testing section of
Group 8A - Battery. Charge or replace the battery, if
required.
2. Refer to Starting System in Group 8W - Wiring
Diagrams. Test and repair the starter feed and/or control
circuits, if required.
3. Refer to Starter Relay in the Diagnosis and Testing
section of this group. Replace the starter relay, if
required.
4. Refer to Ignition Switch and Key Lock Cylinder in the
Diagnosis and Testing section of Group 8D - Ignition
System. Replace the ignition switch, if required.
5. Refer to Park/Neutral Position Switch in the Diagnosis
and Testing section of Group 21 - Transmission. Replace
the park/neutral position switch, if required.
6. Refer to Starter Motor in the Diagnosis and Testing
section of this group. Replace the starter motor assembly,
if required.
7. If all other starting system components and circuits test
OK, replace the starter motor assembly.

STARTER ENGAGES,
FAILS TO TURN
ENGINE.

1. Battery discharged or
faulty.
2. Starting circuit wiring
faulty.
3. Starter motor faulty.
4. Engine seized.

1. Refer to Battery in the Diagnosis and Testing section of
Group 8A - Battery. Charge or replace the battery, if
required.
2. Refer to Starting System in Group 8W - Wiring
Diagrams. Test and repair the starter feed and/or control
circuits, if required.
3. If all other starting system components and circuits test
OK, replace the starter motor assembly.
4. Refer to Engine Diagnosis in the Diagnosis and Testing
section of Group 9 - Engine.

STARTER ENGAGES,
SPINS OUT BEFORE
ENGINE STARTS.

1. Starter ring gear faulty.
2. Starter motor faulty.

1. Refer to Starter Motor in the Removal and Installation
section of this group. Remove the starter motor to inspect
the starter ring gear. Replace the starter ring gear, if
required.
2. If all other starting system components and circuits test
OK, replace the starter motor assembly.

STARTER DOES NOT
DISENGAGE.

1. Starter motor
improperly installed.
2. Starter relay faulty.
3. Ignition switch faulty.
4. Starter motor faulty.

1. Refer to Starter Motor in the Removal and Installation
section of this group. Tighten the starter mounting
hardware to the correct tightness specifications.
2. Refer to Starter Relay in the Diagnosis and Testing
section of this group. Replace the starter relay, if
required.
3. Refer to Ignition Switch and Key Lock Cylinder in the
Diagnosis and Testing section of Group 8D - Ignition
System. Replace the ignition switch, if required.
4. If all other starting system components and circuits test
OK, replace the starter motor assembly.

8B - 4

STARTING SYSTEMS

DN

DIAGNOSIS AND TESTING (Continued)