battery DODGE RAM 2002 Service Owners Manual

BATTERY HOLDDOWN
DESCRIPTION
The battery hold down hardware (Fig. 17) includes
two bolts, two U-nuts and a hold down strap. The
battery hold down bracket consists of a formed steel
rod with a stamped steel angle bracket welded to
each end. The hold down bracket assembly is then
plastic-coated for corrosion protection. Models
equipped with the optional diesel engine have a sec-
ond battery installed in a second battery tray on the
right side of the engine compartment. The hold down
hardware for the right side battery is mirror image of
the hold down hardware used for the left side bat-
tery.
When installing a battery into the battery tray, be
certain that the hold down hardware is properly
installed and that the fasteners are tightened to the
proper specifications. Improper hold down fastener
tightness, whether too loose or too tight, can result in
damage to the battery, the vehicle or both.
OPERATION
The battery holddown secures the battery in the
battery tray. This holddown is designed to prevent
battery movement during the most extreme vehicle
operation conditions. Periodic removal and lubrica-tion of the battery holddown hardware is recom-
mended to prevent hardware seizure at a later date.
CAUTION: Never operate a vehicle without a battery
holddown device properly installed. Damage to the
vehicle, components and battery could result.
REMOVAL
All of the battery hold down hardware except for
the outboard U-nut can be serviced without removal
of the battery or the battery tray. The battery tray
must be removed from the vehicle to service the out-
board U-nut. If the outboard U-nut requires service
replacement, refer toBattery Trayin the index of
this service manual for the location of the proper bat-
tery tray removal and installation procedures.
(1) Turn the ignition switch to the Off position. Be
certain that all electrical accessories are turned off.
(2) Loosen the battery negative cable terminal
clamp pinch-bolt hex nut.
(3) Disconnect the battery negative cable terminal
clamp from the battery negative terminal post. If
necessary, use a battery terminal puller to remove
the terminal clamp from the battery post.
(4) Remove the two battery hold down bolts from
the battery hold down strap (Fig. 18).
Fig. 17 Battery Hold Downs - Typical
1 - BATTERY TRAY
2 - U-NUT (2)
3 - BATTERY
4 - BOLT (2)
5 - HOLD DOWN STRAP
Fig. 18 Left Battery Hold Downs Remove/Install -
Typical for Right Battery
1 - BATTERY TRAY
2 - U-NUT (2)
3 - BATTERY
4 - BOLT (2)
5 - HOLD DOWN STRAP
BR/BEBATTERY SYSTEM 8F - 17

(5) Remove the battery hold down strap from the
top of the battery case.
INSTALLATION
(1) Clean and inspect the battery hold down hard-
ware (Refer to 8 - ELECTRICAL/BATTERY SYSTEM
- CLEANING).
(2) Position the battery hold down strap across the
top of the battery case.
(3) Install and tighten the two battery hold down
bolts through the holes on each end of the hold down
strap and into the U-nuts on each side of the battery
tray. Tighten the bolts to 4 N´m (35 in. lbs.).
(4) Reconnect the battery negative cable terminal
clamp to the battery negative terminal post. Tighten
the terminal clamp pinch-bolt hex nut to 4 N´m (35
in. lbs.).
BATTERY CABLE
DESCRIPTION
The battery cables (Fig. 19) are large gauge,
stranded copper wires sheathed within a heavy plas-
tic or synthetic rubber insulating jacket. The wire
used in the battery cables combines excellent flexibil-
ity and reliability with high electrical current carry-
ing capacity. Refer toWiring Diagramsfor the
location of the proper battery cable wire gauge infor-
mation.The battery cables cannot be repaired and, if dam-
aged or faulty they must be replaced. Both the bat-
tery positive and negative cables are available for
service replacement only as a unit with the battery
positive cable wire harness or the battery negative
cable wire harness, which may include portions of
the wiring circuits for the generator and other com-
ponents on some models.
GASOLINE ENGINE BATTERY CABLES
Gasoline engine models feature a stamped brass
clamping type female battery terminal crimped onto
one end of the battery cable wire and then solder-
dipped. A square headed pinch-bolt and hex nut are
installed at the open end of the female battery termi-
nal clamp. The battery positive cable also includes a
red molded rubber protective cover for the female
battery terminal clamp. Large eyelet type terminals
are crimped onto the opposite end of the battery
cable wire and then solder-dipped. The battery posi-
tive cable wires have a red insulating jacket to pro-
vide visual identification and feature a larger female
battery terminal clamp to allow connection to the
larger battery positive terminal post. The battery
negative cable wires have a black insulating jacket
and a smaller female battery terminal clamp.
DIESEL ENGINE BATTERY CABLES
Diesel engine models feature a clamping type
female battery terminal made of soft lead die cast
onto one end of the battery cable wire. A square
headed pinch-bolt and hex nut are installed at the
open end of the female battery terminal clamp. The
pinch-bolt on the left side battery positive cable
female terminal clamp also has a stud extending
from the head of the bolt. Large eyelet type terminals
are crimped onto the opposite end of the battery
cable wire and then solder-dipped. The battery posi-
tive cable wires have a red insulating jacket to pro-
vide visual identification and feature a larger female
battery terminal clamp to allow connection to the
larger battery positive terminal post. The battery
negative cable wires have a black insulating jacket
and a smaller female battery terminal clamp.
OPERATION
The battery cables connect the battery terminal
posts to the vehicle electrical system. These cables
also provide a return path for electrical current gen-
erated by the charging system for restoring the volt-
age potential of the battery. The female battery
terminal clamps on the ends of the battery cable
wires provide a strong and reliable connection of the
battery cable to the battery terminal posts. The ter-
minal pinch bolts allow the female terminal clamps
to be tightened around the male terminal posts on
Fig. 19 Battery Cables - Typical
1 - EYELET
2 - NUT
3 - POWER DISTRIBUTION CENTER
4 - POSITIVE CABLE
5 - SCREW
6 - NEGATIVE CABLE
7 - EYELET
8 - CLIP
8F - 18 BATTERY SYSTEMBR/BE
BATTERY HOLDDOWN (Continued)

the top of the battery. The eyelet terminals secured
to the ends of the battery cable wires opposite the
female battery terminal clamps provide secure and
reliable connection of the battery to the vehicle elec-
trical system.
GASOLINE ENGINE
The battery positive cable terminal clamp is
crimped onto the ends of two wires. One wire has an
eyelet terminal that connects the battery positive
cable to the B(+) terminal stud of the Power Distri-
bution Center (PDC), and the other wire has an eye-
let terminal that connects the battery positive cable
to the B(+) terminal stud of the engine starter motor
solenoid. The battery negative cable terminal clamp
is also crimped onto the ends of two wires. One wire
has an eyelet terminal that connects the battery neg-
ative cable to the vehicle powertrain through a stud
on the front of the left engine cylinder head. The
other wire has an eyelet terminal that connects the
battery negative cable to the vehicle body through a
ground screw on the left front fender inner shield,
just ahead of the battery. An additional ground wire
with two eyelet terminals is used to provide ground
to the vehicle frame. One eyelet terminal of this
ground wire is installed under the head of the bat-
tery negative cable terminal clamp pinch-bolt, and
the other eyelet terminal is secured with a ground
screw to the outer surface of the left frame rail,
below the battery.
DIESEL ENGINE
The left battery positive cable terminal clamp is
die cast onto the ends of two wires. One wire has an
eyelet terminal that connects the left battery positive
cable to the B(+) terminal stud of the Power Distri-
bution Center (PDC), and the other wire has an eye-
let terminal that connects the left battery positive
cable to the B(+) terminal stud of the engine starter
motor solenoid. The right battery positive cable ter-
minal clamp is die cast onto the end of a single wire.
The eyelet terminal on the other end of the right bat-
tery positive cable is connected to the stud on the
pinch-bolt of the left battery positive cable terminal
clamp. This stud also provides a connection point for
the eyelet terminals from the fuel heater relay and
intake air heater relay jumper harness take outs. All
of these eyelet terminals are secured to the left bat-
tery positive cable terminal clamp pinch-bolt stud
with a single hex nut.The left battery negative cable terminal clamp is
die cast onto the ends of two wires. One wire has an
eyelet terminal that connects the left battery nega-
tive cable to the vehicle powertrain through a ground
screw on the left side of the engine block, below the
power steering and vacuum pumps. The other wire
has an eyelet terminal that connects the left battery
negative cable to the vehicle body through a ground
screw on the left front fender inner shield, just ahead
of the left battery. An additional ground wire with
two eyelet terminals is used to provide ground to the
vehicle frame. One eyelet terminal of this ground
wire is installed under the nut of the left battery
negative cable terminal clamp pinch-bolt, and the
other eyelet terminal is secured with a ground screw
to the outer surface of the left frame rail, below the
left battery. The right battery negative cable terminal
is also die cast onto the ends of two wires. One wire
has an eyelet terminal that connects the right bat-
tery negative cable to the vehicle powertrain through
a ground screw on the right side of the engine block,
just forward of the right engine mount. The other
wire has an eyelet terminal that connects the right
battery negative cable to the vehicle body through a
ground screw on the right front fender inner shield,
just behind the right battery.
DIAGNOSIS AND TESTING - BATTERY CABLES
A voltage drop test will determine if there is exces-
sive resistance in the battery cable terminal connec-
tions or the battery cables. If excessive resistance is
found in the battery cable connections, the connec-
tion point should be disassembled, cleaned of all cor-
rosion or foreign material, then reassembled.
Following reassembly, check the voltage drop for the
battery cable connection and the battery cable again
to confirm repair.
When performing the voltage drop test, it is impor-
tant to remember that the voltage drop is giving an
indication of the resistance between the two points at
which the voltmeter probes are attached.EXAM-
PLE:When testing the resistance of the battery pos-
itive cable, touch the voltmeter leads to the battery
positive cable terminal clamp and to the battery pos-
itive cable eyelet terminal at the starter solenoid
B(+) terminal stud. If you probe the battery positive
terminal post and the battery positive cable eyelet
terminal at the starter solenoid B(+) terminal stud,
you are reading the combined voltage drop in the
battery positive cable terminal clamp-to-terminal
post connection and the battery positive cable.
BR/BEBATTERY SYSTEM 8F - 19
BATTERY CABLE (Continued)

VOLTAGE DROP TEST
WARNING: MODELS EQUIPPED WITH THE DIESEL
ENGINE OPTION ALSO HAVE AN AUTOMATIC
SHUTDOWN (ASD) RELAY LOCATED IN THE
POWER DISTRIBUTION CENTER (PDC), IN THE
ENGINE COMPARTMENT. HOWEVER, REMOVAL OF
THE ASD RELAY MAY NOT PREVENT THE DIESEL
ENGINE FROM STARTING. BE CERTAIN TO ALSO
DISCONNECT THE FUEL SHUTDOWN SOLENOID
WIRE HARNESS CONNECTOR ON MODELS WITH A
DIESEL ENGINE. FAILURE TO DO SO MAY RESULT
IN PERSONAL INJURY.
The following operation will require a voltmeter
accurate to 1/10 (0.10) volt. Before performing this
test, be certain that the following procedures are
accomplished:
²The battery is fully-charged and load tested
(Refer to 8 - ELECTRICAL/BATTERY SYSTEM/BAT-
TERY - STANDARD PROCEDURE).
²Fully engage the parking brake.
²If the vehicle is equipped with an automatic
transmission, place the gearshift selector lever in the
Park position. If the vehicle is equipped with a man-
ual transmission, place the gearshift selector lever in
the Neutral position and block the clutch pedal in the
fully depressed position.
²Verify that all lamps and accessories are turned
off.
²To prevent a gasoline engine from starting,
remove the Automatic ShutDown (ASD) relay. The
ASD relay is located in the Power Distribution Cen-
ter (PDC), in the engine compartment. See the fuse
and relay layout label affixed to the underside of the
PDC cover for ASD relay identification and location.
To prevent a diesel engine from starting, disconnect
the fuel shutdown solenoid wire harness connector
(Fig. 20).
(1) Connect the positive lead of the voltmeter to
the battery negative terminal post. Connect the neg-
ative lead of the voltmeter to the battery negative
cable terminal clamp (Fig. 21). Rotate and hold the
ignition switch in the Start position. Observe the
voltmeter. If voltage is detected, correct the poor con-
nection between the battery negative cable terminal
clamp and the battery negative terminal post.
NOTE: If the vehicle is equipped with a dual battery
system, Step 1 must be performed twice, once for
each battery.
(2) Connect the positive lead of the voltmeter to
the battery positive terminal post. Connect the nega-
tive lead of the voltmeter to the battery positive cable
terminal clamp (Fig. 22). Rotate and hold the ignition
switch in the Start position. Observe the voltmeter. Ifvoltage is detected, correct the poor connection
between the battery positive cable terminal clamp
and the battery positive terminal post.
Fig. 20 Fuel Shutdown Solenoid Connector - Diesel
Engine
1 - AIR TEMPERATURE SENSOR
2 - SENSOR ELECTRICAL CONNECTOR
3 - SOLENOID ELECTRICAL CONNECTOR
4 - FUEL SHUTDOWN SOLENOID
5 - INTAKE MANIFOLD (UPPER HALF)
Fig. 21 Test Battery Negative Connection
Resistance - Typical
1 - VOLTMETER
2 - BATTERY
8F - 20 BATTERY SYSTEMBR/BE
BATTERY CABLE (Continued)

NOTE: If the vehicle is equipped with a dual battery
system, Step 2 must be performed twice, once for
each battery.
(3) Connect the voltmeter to measure between the
battery positive cable terminal clamp and the starter
solenoid B(+) terminal stud (Fig. 23). Rotate and hold
the ignition switch in the Start position. Observe the
voltmeter. If the reading is above 0.2 volt, clean and
tighten the battery positive cable eyelet terminal con-
nection at the starter solenoid B(+) terminal stud.
Repeat the test. If the reading is still above 0.2 volt,
replace the faulty battery positive cable.
NOTE: If the vehicle is equipped with a dual battery
system, Step 3 must be performed on the driver
side battery only.
(4) Connect the voltmeter to measure between the
battery negative cable terminal clamp and a good
clean ground on the engine block (Fig. 24). Rotate
and hold the ignition switch in the Start position.
Observe the voltmeter. If the reading is above 0.2
volt, clean and tighten the battery negative cable
eyelet terminal connection to the engine block.
Repeat the test. If the reading is still above 0.2 volt,
replace the faulty battery negative cable.
NOTE: If the vehicle is equipped with a dual battery
system, Step 4 must be performed twice, once for
each battery.
REMOVAL
POSITIVE CABLE REMOVAL - GASOLINE
ENGINE
Both the battery negative cable and the battery
positive cable are serviced in the battery wire har-
ness. If either battery cable is damaged or faulty, the
battery wire harness assembly must be replaced.
(1) Remove the positive battery cable from the bat-
tery.
(2) Remove the cover from the PDC.
(3) Remove the positive battery cable from the
PDC.
Fig. 22 Test Battery Positive Connection Resistance
- Typical
1 - VOLTMETER
2 - BATTERY
Fig. 23 Test Battery Positive Cable Resistance -
Typical
1 - BATTERY
2 - VOLTMETER
3 - STARTER MOTOR
Fig. 24 Test Ground Circuit
1 - VOLTMETER
2 - BATTERY
3 - ENGINE GROUND
BR/BEBATTERY SYSTEM 8F - 21
BATTERY CABLE (Continued)

(4) Disconnect the starter motor signal wire har-
ness connector, located on the PDC housing.
(5) Disengage wire harness assembly pushpin
retainers.
(6) From under the vehicle, disengage wire har-
ness assembly pushpin retainers.
(7) Remove the positive battery cable from the
starter motor B+ terminal stud.
(8) Remove the starter motor trigger wire from the
starter motor.
(9) Remove the positive cable wire harness assem-
bly from the vehicle.
NEGATIVE CABLE REMOVAL - GASOLINE
ENGINE
Both the battery negative cable and the battery
positive cable are serviced in the battery wire har-
ness. If either battery cable is damaged or faulty, the
battery wire harness unit must be replaced.
(1) Turn the ignition switch to the Off position. Be
certain that all electrical accessories are turned off.
(2) Loosen the battery negative cable terminal
clamp pinch-bolt hex nut.
(3) Disconnect the battery negative cable terminal
clamp from the battery negative terminal post. If
necessary, use a battery terminal puller to remove
the terminal clamp from the battery post.
(4) Remove the negative cable jumper from the left
side of the radiator closure panel.
(5) Remove the negative cable jumper from the left
side of the frame assembly.
(6) Remove the PDC cover and remove the gener-
ator output wire from the PDC.
(7) Following the wire, remove the pushpin retain-
ers holding the wire assembly in place.
(8) Remove the negative cable eyelet from the
power steering pump pivot bolt.
(9) Remove the generator output wire from the
generator.
(10) Remove the negative battery cable assembly,
by fishing out from under the compressor mounting
bracket, if equipped.
INSTALLATION
POSITIVE CABLE INSTALLATION - GASOLINE
ENGINE
(1) Position the battery wire harness into the
engine compartment.
(2) Install the positive battery cable on the battery.
(3) Install the positive battery cable on the PDC.
(4) Install the cover on the PDC.
(5) Connect the starter motor signal wire harness
connector, located on the PDC housing.(6) Install wire harness assembly pushpin retain-
ers in their original position.
(7) From under the vehicle, install wire harness
assembly pushpin retainers.
(8) Install and tighten the nut that secures the
battery positive cable eyelet terminal to the B(+) ter-
minal stud on the starter solenoid. Tighten the nut to
10 N´m (90 in. lbs.).
(9) Connect the starter motor trigger wire on the
starter motor.
(10) Reconnect the battery positive cable terminal
clamp to the battery positive terminal post. Tighten
the terminal clamp pinch-bolt hex nut to 4 N´m (35
in. lbs.).
(11) Apply a thin coating of petroleum jelly or
chassis grease to the exposed surfaces of the battery
cable terminal clamps and the battery terminal
posts.
NEGATIVE CABLE INSTALLATION - GASOLINE
ENGINE
(1) Position the battery wire harness into the
engine compartment and under the compressor
mounting bracket, if equipped.
(2) Install and tighten the nut that secures the
battery negative cable ground eyelet terminal to the
stud on the power steering pump pivot bolt.
(3) Install the generator output cable eyelet termi-
nal onto the generator output terminal stud.
(4) Install and tighten the nut that secures the
generator output cable eyelet terminal to the genera-
tor output terminal stud. Tighten the nut to 8.4 N´m
(75 in. lbs.).
(5) Position the cover for the generator output ter-
minal stud housing onto the back of the generator
and snap it into place.
(6) Secure wire assembly in place with pushpin
retainers in there original positions.
(7) Install and tighten the screw that secures the
battery negative cable eyelet terminal to the radiator
closure panel, near the battery. Tighten the screw to
40 in. lbs.
(8) Install and tighten the screw that secures the
battery negative cable eyelet terminal to the left
front side of the frame assembly. Tighten the screw
to 80 in. lbs.
(9) Install and tighten the nut that secures the
battery positive cable eyelet terminal and the gener-
ator output cable eyelet terminal to the PDC B(+)
terminal stud. Tighten the nut to 80 in. lbs.
(10) Reconnect the battery negative cable terminal
clamp to the battery negative terminal post. Tighten
the terminal clamp pinch-bolt hex nut to 35 in. lbs.
(11)
Apply a thin coating of petroleum jelly or chas-
sis grease to the exposed surfaces of the battery cable
terminal clamps and the battery terminal posts.
8F - 22 BATTERY SYSTEMBR/BE
BATTERY CABLE (Continued)

BATTERY TRAY
DESCRIPTION
The battery is mounted in a molded plastic tray
(Fig. 25) with an integral support located in the left
front corner of the engine compartment. A U-nut held
in a molded formation on each side of the battery
tray provides anchor points for the battery hold down
bolts. The battery tray is secured on the outboard
side to the inner fender shield by two hex screws
with washers, and from underneath the integral bat-
tery tray support is secured to the left front wheel-
house inner panel by two stud plates. Each stud
plate has two studs and is secured by two nuts with
washers. The stud plate that secures the front of the
battery tray support to the wheelhouse inner panel is
installed through the wheelhouse panel from the top.
The stud plate that secures the rear of the battery
tray support to the wheelhouse inner panel is
installed through the wheelhouse panel from the bot-
tom.
A hole in the bottom of the battery tray is fitted
with a battery temperature sensor (Refer to 8 -
ELECTRICAL/CHARGING/BATTERY TEMPERA-
TURE SENSOR - DESCRIPTION). Models that are
equipped with an optional vehicle speed control sys-tem have the speed control servo secured to the inte-
gral battery tray support.
Models that are equipped with the diesel engine
option have a second battery tray located in the right
front corner of the engine compartment. This second
battery tray and its mounting are mirror image of
the standard equipment left battery tray. However,
the right battery tray and support have no provisions
for a battery temperature sensor or a speed control
servo mounting bracket.
OPERATION
The battery tray provides a secure mounting loca-
tion and supports the battery. On some vehicles, the
battery tray also provides the anchor point/s for the
battery holddown hardware. The battery tray and
the battery holddown hardware combine to secure
and stabilize the battery in the engine compartment,
which prevents battery movement during vehicle
operation. Unrestrained battery movement during
vehicle operation could result in damage to the vehi-
cle, the battery, or both.
REMOVAL
(1) Remove the battery from the battery tray
(Refer to 8 - ELECTRICAL/BATTERY SYSTEM/BAT-
TERY - REMOVAL).
(2) If the left battery tray is being removed,
remove the battery temperature sensor from the left
battery tray (Refer to 8 - ELECTRICAL/CHARGING/
BATTERY TEMPERATURE SENSOR - REMOVAL).
(3) Remove the two screws with washers that
secure the outboard side of the battery tray to the
inner fender shield (Fig. 26).
(4) From the engine compartment, remove the two
nuts with washers that secure the rear of the battery
tray support to the two studs that extend through
the top of the front wheelhouse inner panel.
(5) From inside the front fender wheelhouse,
remove the two nuts with washers that secure the
front of the battery tray support to the two studs
that extend through the underside of the front wheel-
house inner panel.
(6) From inside the front fender wheelhouse,
remove the stud plate that secures the rear of the
battery tray support from the underside of the front
wheelhouse inner panel.
(7) From the engine compartment, remove the bat-
tery tray and the stud plate that secures the front of
the battery tray support from the front wheelhouse
inner panel as a unit.
(8) If the vehicle is equipped with the optional
vehicle speed control package, the speed control servo
must be removed from the left battery tray support
to complete battery tray removal.
Fig. 25 Battery Tray - Typical
1 - STUD PLATE (2)
2 - NUT AND WASHER (4)
3 - FRONT WHEELHOUSE INNER PANEL
4 - SPEED CONTROL SERVO
5 - TRAY
6 - SCREW AND WASHER (2)
7 - BATTERY TREMPERATURE SENSOR
8 - U-NUT (2)
9 - FENDER INNER SHIELD
BR/BEBATTERY SYSTEM 8F - 23

INSTALLATION
(1) Clean and inspect the battery tray (Refer to 8 -
ELECTRICAL/BATTERY SYSTEM - CLEANING).
(2) If the vehicle is equipped with the optional
vehicle speed control package, the speed control servo
must be installed onto the left battery tray support
to complete battery tray installation.(3) Install the stud plate onto the front of the bat-
tery tray support.
(4) From the engine compartment, position the
battery tray and the stud plate that secures the front
of the battery tray support onto the front wheelhouse
inner panel as a unit.
(5) From inside the front fender wheelhouse,
loosely install the two nuts with washers that secure
the front of the battery tray support to the two studs
that extend through the underside of the front wheel-
house inner panel.
(6) From inside the front fender wheelhouse, posi-
tion the stud plate that secures the rear of the bat-
tery tray support onto the underside of the front
wheelhouse inner panel.
(7) From the engine compartment, loosely install
the two nuts with washers that secure the rear of the
battery tray support to the two studs that extend
through the top of the front wheelhouse inner panel.
(8) Install and tighten the two screws with wash-
ers that secure the outboard side of the battery tray
to the inner fender shield. Tighten the screws to 15.8
N´m (140 in. lbs.).
(9) Final tighten the four nuts with washers that
secure the battery tray support to the stud plates on
the front wheelhouse inner panel. Tighten the nuts
to 15.8 N´m (140 in. lbs.).
(10) If the left battery tray is being installed,
install the battery temperature sensor onto the left
battery tray (Refer to 8 - ELECTRICAL/CHARGING/
BATTERY TEMPERATURE SENSOR - INSTALLA-
TION).
(11) Install the battery onto the battery tray (Refer
to 8 - ELECTRICAL/BATTERY SYSTEM/BATTERY -
INSTALLATION).
Fig. 26 Left Battery Tray Remove/Install - Typical for
Right Battery Tray
1 - STUD PLATE (2)
2 - NUT AND WASHER (4)
3 - FRONT WHEELHOUSE INNER PANEL
4 - SPEED CONTROL SERVO
5 - TRAY
6 - SCREW AND WASHER (2)
7 - BATTERY TREMPERATURE SENSOR
8 - U-NUT (2)
9 - FENDER INNER SHIELD
8F - 24 BATTERY SYSTEMBR/BE
BATTERY TRAY (Continued)

CHARGING
TABLE OF CONTENTS
page page
CHARGING
DESCRIPTION.........................25
OPERATION...........................25
DIAGNOSIS AND TESTING - CHARGING
SYSTEM............................25
SPECIFICATIONS
GENERATOR RATINGS.................26
SPECIFICATIONS - TORQUE -
GENERATOR/CHARGING SYSTEM........27
BATTERY TEMPERATURE SENSOR
DESCRIPTION.........................27OPERATION...........................27
REMOVAL.............................27
INSTALLATION.........................28
GENERATOR
DESCRIPTION.........................28
OPERATION...........................28
REMOVAL.............................28
INSTALLATION.........................30
VOLTAGE REGULATOR
DESCRIPTION.........................30
OPERATION...........................30
CHARGING
DESCRIPTION
The charging system consists of:
²Generator
²Electronic Voltage Regulator (EVR) circuitry
within the Powertrain Control Module (PCM)
²Ignition switch
²Battery (refer to 8, Battery for information)
²Battery temperature sensor
²Check Gauges Lamp (if equipped)
²Voltmeter (refer to 8, Instrument Panel and
Gauges for information)
²Wiring harness and connections (refer to 8, Wir-
ing Diagrams for information)
OPERATION
The charging system is turned on and off with the
ignition switch. The system is on when the engine is
running and the ASD relay is energized. When the
ASD relay is on, voltage is supplied to the ASD relay
sense circuit at the PCM. This voltage is connected
through the PCM and supplied to one of the genera-
tor field terminals (Gen. Source +) at the back of the
generator.
The amount of direct current produced by the gen-
erator is controlled by the EVR (field control) cir-
cuitry contained within the PCM. This circuitry is
connected in series with the second rotor field termi-
nal and ground.
A battery temperature sensor, located in the bat-
tery tray housing, is used to sense battery tempera-
ture. This temperature data, along with data from
monitored line voltage, is used by the PCM to vary
the battery charging rate. This is done by cycling theground path to control the strength of the rotor mag-
netic field. The PCM then compensates and regulates
generator current output accordingly.
All vehicles are equipped with On-Board Diagnos-
tics (OBD). All OBD-sensed systems, including EVR
(field control) circuitry, are monitored by the PCM.
Each monitored circuit is assigned a Diagnostic Trou-
ble Code (DTC). The PCM will store a DTC in elec-
tronic memory for certain failures it detects. Refer to
On-Board Diagnostics in 25, Emission Control Sys-
tem for more DTC information and a list of codes.
The Check Gauges Lamp (if equipped) monitors:
charging system voltage,engine coolant tempera-
ture and engine oil pressure. If an extreme condition
is indicated, the lamp will be illuminated. This is
done as reminder to check the three gauges. The sig-
nal to activate the lamp is sent via the CCD bus cir-
cuits. The lamp is located on the instrument panel.
Refer to 8, Instrument Panel and Gauges for addi-
tional information.
DIAGNOSIS AND TESTING - CHARGING
SYSTEM
The following procedures may be used to diagnose
the charging system if:
²the check gauges lamp (if equipped) is illumi-
nated with the engine running
²the voltmeter (if equipped) does not register
properly
²an undercharged or overcharged battery condi-
tion occurs.
Remember that an undercharged battery is often
caused by:
²accessories being left on with the engine not
running
BR/BECHARGING 8F - 25

²a faulty or improperly adjusted switch that
allows a lamp to stay on. Refer to Ignition-Off Draw
Test in 8, Battery for more information.
INSPECTION
The Powertrain Control Module (PCM) monitors
critical input and output circuits of the charging sys-
tem, making sure they are operational. A Diagnostic
Trouble Code (DTC) is assigned to each input and
output circuit monitored by the On-Board Diagnostic
(OBD) system. Some charging system circuits are
checked continuously, and some are checked only
under certain conditions.
Refer to Diagnostic Trouble Codes in; Powertrain
Control Module; Electronic Control Modules for more
DTC information. This will include a complete list of
DTC's including DTC's for the charging system.
To perform a complete test of the charging system,
refer to the appropriate Powertrain Diagnostic Proce-
dures service manual and the DRBtscan tool. Per-
form the following inspections before attaching the
scan tool.
(1) Inspect the battery condition. Refer to 8, Bat-
tery for procedures.(2) Inspect condition of battery cable terminals,
battery posts, connections at engine block, starter
solenoid and relay. They should be clean and tight.
Repair as required.
(3) Inspect all fuses in both the fuseblock and
Power Distribution Center (PDC) for tightness in
receptacles. They should be properly installed and
tight. Repair or replace as required.
(4) Inspect generator mounting bolts for tightness.
Replace or tighten bolts if required. Refer to the Gen-
erator Removal/Installation section of this group for
torque specifications.
(5) Inspect generator drive belt condition and ten-
sion. Tighten or replace belt as required. Refer to
Belt Tension Specifications in 7, Cooling System.
(6) Inspect automatic belt tensioner (if equipped).
Refer to 7, Cooling System for information.
(7) Inspect generator electrical connections at gen-
erator field, battery output, and ground terminal (if
equipped). Also check generator ground wire connec-
tion at engine (if equipped). They should all be clean
and tight. Repair as required.
SPECIFICATIONS
GENERATOR RATINGS
TYPE PART NUMBER RATED SAE AMPS ENGINESMINIMUM TEST
AMPS
DENSO 56028920AB 1365.9L
GAS100
DENSO 56029913AA 1175.9L
GAS90
BOSCH 56028237AB 1175.9L
GAS90
BOSCH 56028238AB 1365.9L
GAS100
DENSO 56027221AD 1365.9L
DIESEL120
BOSCH 56028239AB 1365.9L
DIESEL120
BOSCH 56028560AA 136 8.0L 100
DENSO 560289200AC 136 8.0L 100
8F - 26 CHARGINGBR/BE
CHARGING (Continued)