service CHRYSLER VOYAGER 2004 Service Manual

found on the original equipment battery label. Be
certain that a replacement battery has the correct
Group Size number, as well as CCA, and RC or AH
ratings that equal or exceed the original equipment
specification for the vehicle being serviced. Refer to
Battery Specificationsin this group for the loca-
tion of the proper factory-installed battery specifica-
tions.
OPERATION
The battery is designed to store electrical energy in
a chemical form. When an electrical load is applied to
the terminals of the battery, an electrochemical reac-
tion occurs. This reaction causes the battery to dis-
charge electrical current from its terminals. As the
battery discharges, a gradual chemical change takes
place within each cell. The sulfuric acid in the elec-
trolyte combines with the plate materials, causing
both plates to slowly change to lead sulfate. At the
same time, oxygen from the positive plate material
combines with hydrogen from the sulfuric acid, caus-
ing the electrolyte to become mainly water. The
chemical changes within the battery are caused by
the movement of excess or free electrons between the
positive and negative plate groups. This movement of
electrons produces a flow of electrical current
through the load device attached to the battery ter-
minals. As the plate materials become more similar chem-
ically, and the electrolyte becomes less acid, the volt-
age potential of each cell is reduced. However, by
charging the battery with a voltage higher than that
of the battery itself, the battery discharging process
is reversed. Charging the battery gradually changes
the sulfated lead plates back into sponge lead and
lead dioxide, and the water back into sulfuric acid.
This action restores the difference in the electron
charges deposited on the plates, and the voltage
potential of the battery cells. For a battery to remain
useful, it must be able to produce high-amperage cur-
rent over an extended period. A battery must also be
able to accept a charge, so that its voltage potential
may be restored. The battery is vented to release excess hydrogen
gas that is created when the battery is being charged
or discharged. However, even with these vents,
hydrogen gas can collect in or around the battery. If
hydrogen gas is exposed to flame or sparks, it may
ignite. If the electrolyte level is low, the battery may
arc internally and explode. If the battery is equipped
with removable cell caps, add distilled water when-
ever the electrolyte level is below the top of the
plates. If the battery cell caps cannot be removed, the
battery must be replaced if the electrolyte level
becomes low.
DIAGNOSIS AND TESTING - BATTERY
The battery must be completely charged and the
terminals should be properly cleaned and inspected
before diagnostic procedures are performed. Refer to
Battery System Cleaning for the proper cleaning pro-
cedures, and Battery System Inspection for the
proper battery inspection procedures. Refer to Stan-
dard Procedures for the proper battery charging pro-
cedures.
MICRO 420 BATTERY TESTER
The Micro 420 automotive battery tester is
designed to help the dealership technicians diagnose
the cause of a defective battery. Follow the instruc-
tion manual supplied with the tester to properly
diagnose a vehicle. If the instruction manual is not
available refer to the standard procedure in this sec-
tion, which includes the directions for using the
Micro 420 battery tester.
WARNING: IF THE BATTERY SHOWS SIGNS OF
FREEZING, LEAKING OR LOOSE POSTS, DO NOT
TEST, ASSIST-BOOST, OR CHARGE. THE BATTERY
MAY ARC INTERNALLY AND EXPLODE. PERSONAL
INJURY AND/OR VEHICLE DAMAGE MAY RESULT.
WARNING: EXPLOSIVE HYDROGEN GAS FORMS IN
AND AROUND THE BATTERY. DO NOT SMOKE,
USE FLAME, OR CREATE SPARKS NEAR THE BAT-
TERY. PERSONAL INJURY AND/OR VEHICLE DAM-
AGE MAY RESULT.
WARNING: THE BATTERY CONTAINS SULFURIC
ACID, WHICH IS POISONOUS AND CAUSTIC. AVOID
CONTACT WITH THE SKIN, EYES, OR CLOTHING.
IN THE EVENT OF CONTACT, FLUSH WITH WATER
AND CALL A PHYSICIAN IMMEDIATELY. KEEP OUT
OF THE REACH OF CHILDREN.
A battery that will not accept a charge is faulty,
and must be replaced. Further testing is not
required. A fully-charged battery must be tested to
determine its cranking capacity. A battery that is ful-
ly-charged, but does not pass the Micro 420 or load
test, is faulty and must be replaced.
NOTE: Completely discharged batteries may take
several hours to accept a charge. Refer to Standard
Procedures for the proper battery charging proce-
dures.
RS BATTERY SYSTEM8Fs-9
BATTERY (Continued)

STANDARD PROCEDURE
STANDARD PROCEDURE - SPIRAL PLATE
BATTERY CHARGING
Vehicles equipped with a diesel engine utilize a
unique spiral plate battery. This battery has a maxi-
mum charging voltage that must not be exceeded in
order to restore the battery to its full potential, fail-
ure to use the following spiral plate battery charging
procedure could result in damage to the battery or
personal injury. Battery charging is the means by which the bat-
tery can be restored to its full voltage potential. A
battery is fully-charged when: ² Micro 420 battery tester indicates battery is OK.
² Open-circuit voltage of the battery is 12.65 volts
or above. ² Battery passes Load Test multiple times.
WARNING: IF THE BATTERY SHOWS SIGNS OF
FREEZING, LEAKING, LOOSE POSTS OR LOW
ELECTROLYTE LEVEL, DO NOT TEST, ASSIST-
BOOST, OR CHARGE. THE BATTERY MAY ARC
INTERNALLY AND EXPLODE. PERSONAL INJURY
AND/OR VEHICLE DAMAGE MAY RESULT.
CAUTION: Always disconnect and isolate the bat-
tery negative cable before charging a battery.
Charge the battery directly at the battery terminals.
Do not exceed 14.4 volts while charging a battery.
CAUTION: The battery should not be hot to the
touch. If the battery feels hot to the touch, turn off
the charger and let the battery cool before continu-
ing the charging operation. Damage to the battery
may result. After the battery has been charged to 12.6 volts or
greater, perform a load test to determine the battery
cranking capacity. Refer to Battery Diagnosis and
Testing for the proper battery test procedures. If the
battery will endure a load test, return the battery to
service. If the battery will not pass a load test, it is
faulty and must be replaced. Clean and inspect the battery hold downs, tray,
terminals, posts, and top before completing battery
service. Refer to Battery System Cleaning for the
proper battery system cleaning procedures, and Bat-
tery System Inspection for the proper battery system
inspection procedures.
CHARGING A COMPLETELY DISCHARGED
BATTERY ± SPIRAL PLATE BATTERY
The following procedure should be used to recharge
a completely discharged battery. Unless this proce- dure is properly followed, a good battery may be
needlessly replaced.
(1) Measure the voltage at the battery posts with a
voltmeter, accurate to 1/10 (0.10) volt (Fig. 7). Refer
to Battery Removal and Installation for access
instructions. If the reading is below ten volts, the
battery charging current will be low. It could take
several hours before the battery accepts a current
greater than a few milliamperes. Such low current
may not be detectable on the ammeters built into
many battery chargers.
(2) Disconnect and isolate the battery negative
cable. Connect the battery charger leads. Some bat-
tery chargers are equipped with polarity-sensing cir-
cuitry. This circuitry protects the battery charger and
the battery from being damaged if they are improp-
erly connected. If the battery state-of-charge is too
low for the polarity-sensing circuitry to detect, the
battery charger will not operate. This makes it
appear that the battery will not accept charging cur-
rent. See the instructions provided by the manufac-
turer of the battery charger for details on how to
bypass the polarity-sensing circuitry. (3) Battery chargers vary in the amount of voltage
and current they provide. The amount of time
required for a battery to accept measurable charging
current at various voltages is shown in the Charge
Rate Table. If the charging current is still not mea-
surable at the end of the charging time, the battery
is faulty and must be replaced. If the charging cur-
rent is measurable during the charging time, the bat-
tery may be good and the charging should be
completed in the normal manner.
Fig. 7 Voltmeter - Typical
8Fs - 10 BATTERY SYSTEMRS
BATTERY (Continued)

CAUTION: The battery should not be hot to the
touch. If the battery feels hot to the touch, turn off
the charger and let the battery cool before continu-
ing the charging operation. Damage to the battery
may result.After the battery has been charged to an open-cir-
cuit voltage reading of 12.4 volts or greater, retest
the battery with the Micro 420 tester or perform a
load test to determine the battery cranking capacity.
Refer to Standard Procedures for the proper battery
load test procedures. If the battery will pass a load
test, return the battery to service. If the battery will
not pass a load test, it is faulty and must be
replaced. Clean and inspect the battery hold downs, tray,
terminals, posts, and top before completing battery
service. Refer to Battery System Cleaning for the
proper battery system cleaning procedures, and Bat-
tery System Inspection for the proper battery system
inspection procedures.
CHARGING A COMPLETELY DISCHARGED
CONVENTIONAL BATTERY
The following procedure should be used to recharge
a completely discharged battery. Unless this proce-
dure is properly followed, a good battery may be
needlessly replaced. (1) Measure the voltage at the battery posts with a
voltmeter, accurate to 1/10 (0.10) volt (Fig. 8). If the
reading is below ten volts, the battery charging cur-
rent will be low. It could take some time before the
battery accepts a current greater than a few milliam-
peres. Such low current may not be detectable on the
ammeters built into many battery chargers.
(2) Disconnect and isolate the battery negative
cable. Connect the battery charger leads. Some bat-
tery chargers are equipped with polarity-sensing cir-
cuitry. This circuitry protects the battery charger and
the battery from being damaged if they are improp- erly connected. If the battery state-of-charge is too
low for the polarity-sensing circuitry to detect, the
battery charger will not operate. This makes it
appear that the battery will not accept charging cur-
rent. See the instructions provided by the manufac-
turer of the battery charger for details on how to
bypass the polarity-sensing circuitry.
(3) Battery chargers vary in the amount of voltage
and current they provide. The amount of time
required for a battery to accept measurable charging
current at various voltages is shown in the Charge
Rate Table. If the charging current is still not mea-
surable at the end of the charging time, the battery
is faulty and must be replaced. If the charging cur-
rent is measurable during the charging time, the bat-
tery may be good and the charging should be
completed in the normal manner.
CONVENTIONAL BATTERY CHARGE RATE TABLE
Voltage Minutes
16.0 volts maximum up to 10 min. 14.0 to 15.9 volts up to 20 min.13.9 volts or less up to 30 min.
CHARGING TIME REQUIRED
The time required to charge a battery will vary,
depending upon the following factors: ² Battery Capacity - A completely discharged
heavy-duty battery requires twice the charging time
of a small capacity battery. ² Temperature - A longer time will be needed to
charge a battery at -18É C (0É F) than at 27É C (80É
F). When a fast battery charger is connected to a cold
battery, the current accepted by the battery will be
very low at first. As the battery warms, it will accept
a higher charging current rate (amperage). ² Charger Capacity - A battery charger that
supplies only five amperes will require a longer
charging time. A battery charger that supplies
twenty amperes or more will require a shorter charg-
ing time. ² State-Of-Charge - A completely discharged bat-
tery requires more charging time than a partially
discharged battery. Electrolyte is nearly pure water
in a completely discharged battery. At first, the
charging current (amperage) will be low. As the bat-
tery charges, the specific gravity of the electrolyte
will gradually rise. The Conventional Battery Charging Time Table
gives an indication of the time required to charge a
typical battery at room temperature based upon the
battery state-of-charge and the charger capacity.
Fig. 8 Voltmeter - Typical
8Fs - 12 BATTERY SYSTEMRS
BATTERY (Continued)

CONVENTIONAL BATTERY CHARGING TIME TABLECharging
Amperage 5 Amps10
Amps 20 Amps
Open Circuit Voltage Hours Charging @ 21É C (70É
F)
12.25 to 12.49 6 hours 3 hours 1.5 hours
12.00 to 12.24 10 hours 5 hours 2.5 hours
10.00 to 11.99 14 hours 7 hours 3.5 hours
Below 10.00 18 hours 9 hours 4.5 hours
STANDARD PROCEDURE - OPEN-CIRCUIT
VOLTAGE TEST
A battery open-circuit voltage (no load) test will
show the approximate state-of-charge of a battery.
This test can be used if no other battery tester is
available. Before proceeding with this test, completely charge
the battery. Refer to Standard Procedures for the
proper battery charging procedures. (1) Before measuring the open-circuit voltage, the
surface charge must be removed from the battery.
Turn on the headlamps for fifteen seconds, then
allow up to five minutes for the battery voltage to
stabilize. (2) Disconnect and isolate both battery cables, neg-
ative cable first. (3) Using a voltmeter connected to the battery
posts (see the instructions provided by the manufac-
turer of the voltmeter), measure the open-circuit volt-
age (Fig. 9).
See the Open-Circuit Voltage Table. This voltage
reading will indicate the battery state-of-charge, but
will not reveal its cranking capacity. If a battery has
an open-circuit voltage reading of 12.4 volts or greater, it may be load tested to reveal its cranking
capacity. Refer to Standard Procedures for the proper
battery load test procedures.
OPEN CIRCUIT VOLTAGE TABLE
Open Circuit Voltage Charge Percentage 11.7 volts or less 0% 12.0 volts 25%
12.2 volts 50%
12.45 volts 75%
12.65 volts or more 100%
STANDARD PROCEDURE - IGNITION-OFF
DRAW TEST
The term Ignition-Off Draw (IOD) identifies a nor-
mal condition where power is being drained from the
battery with the ignition switch in the Off position. A
normal vehicle electrical system will draw from fif-
teen to twenty-five milliamperes (0.015 to 0.025
ampere) with the ignition switch in the Off position,
and all non-ignition controlled circuits in proper
working order. Up to twenty-five milliamperes are
needed to enable the memory functions for the Pow-
ertrain Control Module (PCM), digital clock, electron-
ically tuned radio, and other modules which may
vary with the vehicle equipment. A vehicle that has not been operated for approxi-
mately twenty-one days, may discharge the battery
to an inadequate level. When a vehicle will not be
used for twenty-one days or more (stored), remove
the IOD fuse from the Integrated Power Module
(IPM). This will reduce battery discharging. Excessive IOD can be caused by:
² Electrical items left on.
² Faulty or improperly adjusted switches.
² Faulty or shorted electronic modules and compo-
nents. ² An internally shorted generator.
² Intermittent shorts in the wiring.
If the IOD is over twenty-five milliamperes, the
problem must be found and corrected before replac-
ing a battery. In most cases, the battery can be
charged and returned to service after the excessive
IOD condition has been corrected. (1) Verify that all electrical accessories are off.
Turn off all lamps, remove the ignition key, and close
all doors. If the vehicle is equipped with an illumi-
nated entry system or an electronically tuned radio,
allow the electronic timer function of these systems
to automatically shut off (time out). This may take
up to twenty minutes. (2) Disconnect the battery negative cable.
(3) Set an electronic digital multi-meter to its
highest amperage scale. Connect the multi-meter
Fig. 9 Testing Open-Circuit Voltage - Typical
RS BATTERY SYSTEM8Fs-13
BATTERY (Continued)

between the disconnected battery negative cable ter-
minal clamp and the battery negative terminal post.
Make sure that the doors remain closed so that the
illuminated entry system is not activated. The multi-
meter amperage reading may remain high for up to
three minutes, or may not give any reading at all
while set in the highest amperage scale, depending
upon the electrical equipment in the vehicle. The
multi-meter leads must be securely clamped to the
battery negative cable terminal clamp and the bat-
tery negative terminal post. If continuity between the
battery negative terminal post and the negative cable
terminal clamp is lost during any part of the IOD
test, the electronic timer function will be activated
and all of the tests will have to be repeated.(4) After about three minutes, the high-amperage
IOD reading on the multi-meter should become very
low or nonexistent, depending upon the electrical
equipment in the vehicle. If the amperage reading
remains high, remove and replace each fuse or circuit
breaker in the Integrated Power Module (IPM), one
at a time until the amperage reading becomes very
low, or nonexistent. Refer to the appropriate wiring
information in this service manual for complete Inte-
grated Power Module fuse, circuit breaker, and cir-
cuit identification. This will isolate each circuit and
identify the circuit that is the source of the high-am-
perage IOD. If the amperage reading remains high
after removing and replacing each fuse and circuit
breaker, disconnect the wire harness from the gener-
ator. If the amperage reading now becomes very low
or nonexistent, refer to Charging System for the
proper charging system diagnosis and testing proce-
dures. After the high-amperage IOD has been cor-
rected, switch the multi-meter to progressively lower
amperage scales and, if necessary, repeat the fuse
and circuit breaker remove-and-replace process to
identify and correct all sources of excessive IOD. It is
now safe to select the lowest milliampere scale of the
multi-meter to check the low-amperage IOD.
CAUTION: Do not open any doors, or turn on any
electrical accessories with the lowest milliampere
scale selected, or the multi-meter may be damaged.
(5) Allow twenty minutes for the IOD to stabilize
and observe the multi-meter reading. The low-amper-
age IOD should not exceed twenty-five milliamperes
(0.025 ampere). If the current draw exceeds twenty-
five milliamperes, isolate each circuit using the fuse
and circuit breaker remove-and-replace process in
Step 4. The multi-meter reading will drop to within
the acceptable limit when the source of the excessive
current draw is disconnected. Repair this circuit as
required; whether a wiring short, incorrect switch
adjustment, or a component failure is at fault.STANDARD PROCEDURE - CHECKING BATTERY
ELECTROLYTE LEVEL
The following procedure can be used to check the
electrolyte level in a low-maintenance lead-acid bat-
tery. (1) Unscrew and remove the battery cell caps with
a flat-bladed screw driver (Fig. 10).
WARNING: NEVER PUT YOUR FACE NEAR A GAS-
SING, HOT OR SWELLED BATTERY. SERIOUS PER-
SONAL INJURY MAY RESULT.
(2) Wearing safety glasses, look through the bat-
tery cell cap holes to determine the level of the elec-
trolyte in the battery. The electrolyte should be above
the hooks inside the battery cells (Fig. 11). (3) Add only distilled water until the electrolyte
is above the hooks inside the battery cells (Fig. 11).
REMOVAL - BATTERY
WARNING: A SUITABLE PAIR OF HEAVY DUTY
RUBBER GLOVES AND SAFETY GLASSES SHOULD
BE WORN WHEN REMOVING OR SERVICING A
BATTERY.
Fig. 10 BATTERY CELL CAP REMOVAL/
INSTALLATION - LOW-MAINTENANCE BATTERY ONLY
1 - BATTERY CELL CAP
2 - BATTERY CASE
8Fs - 14 BATTERY SYSTEMRS
BATTERY (Continued)

WARNING: REMOVE METALLIC JEWELRY TO
AVOID INJURY BY ACCIDENTAL ARCING OF BAT-
TERY CURRENT.(1) Verify that the ignition switch and all accesso-
ries are OFF. (2) Disconnect the battery cables from the battery
posts, negative first (Fig. 12). (3) Remove the battery hold down retaining nut.
(4) Remove the battery hold down bracket.
(5) Remove the battery from the vehicle.
INSTALLATION
(1) Position the battery in the battery tray.
(2) Install the battery hold down bracket and
retaining nut. Torque the nut to 20 N´m (180 in. lbs.). (3) Connect the battery cables to the battery posts,
positive cable first. Torque terminal fasteners to 5
N´m (40 in. lbs.).
BATTERY HOLDDOWN
DESCRIPTION
The battery hold down hardware consists of a
molded plastic lip that is integral to the outboard
edge of the battery tray and support unit, a molded
steel hold down bracket and a single hex nut with a
coned washer. 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. Refer to
Battery Hold Downs in this section of this service
manual for the location of the proper battery hold
down installation procedures, including the proper
hold down fastener tightness specifications.
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.
NOTE: 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 can be ser-
viced without removal of the battery or the battery
tray and support unit. (1) Turn the ignition switch to the Off position. Be
certain that all electrical accessories are turned off.
Fig. 11 HOOK INSIDE BATTERY CELLS - LOW- MAINTENANCE BATTERY ONLY
1 - TOP OF BATTERY
2 - HOOK INSIDE BATTERY CELLS
Fig. 12 BATTERY POSITION & ORIENTATION
1 - BATTERY THERMOWRAP (IF EQUIPPED)
2 - INTEGRATED POWER MODULE
3 - FRONT CONTROL MODULE
RS BATTERY SYSTEM8Fs-15
BATTERY (Continued)

(2) Remove the nut with washer that secures the
battery hold down bracket to the battery tray and
support unit. (3) Remove the battery hold down bracket from
the battery tray and support unit.
INSTALLATION
(1) Install the battery hold down bracket in the
battery tray and support unit. (2) Install the nut with washer that secures the
battery hold down bracket to the battery tray and
support unit. Torque to 20 N´m (180 in. lbs.).
BATTERY CABLES
DESCRIPTION
The battery cables are large gauge, stranded cop-
per wires sheathed within a heavy plastic or syn-
thetic rubber insulating jacket. The wire used in the
battery cables combines excellent flexibility and reli-
ability with high electrical current carrying capacity.
Refer to Wiring Diagrams in the index of this ser-
vice manual for the location of the proper battery
cable wire gauge information. A clamping type female battery terminal made of
stamped metal is attached to 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. Large eyelet type terminals are
crimped onto the opposite end of the battery cable
wire and then solder-dipped. The battery positive
cable wires have a red insulating jacket to provide
visual identification and feature a larger female bat-
tery 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. 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
wire harness, which may include portions of the wir-
ing circuits for the generator and other components
on some models. Refer to Wiring Diagramsin the
index of this service manual for the location of more
information on the various wiring circuits included in
the battery wire harness for the vehicle being ser-
viced.
OPERATION
The battery cables connect the battery terminal
posts to the vehicle electrical system. These cables
also provide a path back to the battery for electrical
current generated by the charging system for restor-
ing the voltage 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 terminal pinch bolts allow the female terminal
clamps to be tightened around the male terminal
posts on the top of the battery. The eyelet terminals
secured to the opposite ends of the battery cable
wires from the female battery terminal clamps pro-
vide secure and reliable connection of the battery
cables to the vehicle electrical system.
The battery positive cable terminal clamp is
attached to the ends of two wires. One wire has an
eyelet terminal that connects the battery positive
cable to the B(+) terminal stud of the Integrated
Power Module (IPM), 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 attached to 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 left side of the engine cylinder block. 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,
near the battery.
DIAGNOSIS AND TESTING - BATTERY CABLE
A voltage drop test will determine if there is exces-
sive resistance in the battery cable terminal connec-
tions or the battery cable. 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.
VOLTAGE DROP TEST
The following operation will require a voltmeter
accurate to 1/10 (0.10) volt. Before performing this
8Fs - 16 BATTERY SYSTEMRS
BATTERY HOLDDOWN (Continued)

uum reservoir provides a storage container for engine
vacuum. Refer to the engine section of the service
manual for more engine vacuum information. The
drainage hose provides means for any liquid that
might collect in the bottom of the battery tray to
drain under the vehicle.
REMOVAL
(1) Disconnect and isolate the negative battery
cable. (2) Remove the battery from the vehicle. Refer to
the procedure in this section. (3) Remove the battery tray retaining fasteners
(Fig. 18).
(4) Pull battery tray up far enough to disconnect
the engine vacuum harness hose from the battery
tray mounted, vacuum reservoir. (5) Remove the battery tray from the vehicle.
INSTALLATION
(1) Position the battery tray in the vehicle.
(2) Connect the engine vacuum harness hose on
the battery tray mounted vacuum reservoir. (3) Position drainage hose and install the battery
tray retaining fasteners (Fig. 18). (4) Install the battery in the vehicle. Refer to the
procedure in this section. (5) Connect the negative battery cable.
THERMOWRAP
DESCRIPTION
A one-piece slip-on thermowrap unit shields the
battery case from engine compartment heat. The
thermowrap slips over the battery case and due to its
one piece design, the battery cables must be removed
in order to install or remove the thermowrap.
OPERATION
The thermowrap protects the battery from engine
compartment temperature extremes. The tempera-
ture of the battery can affect battery life. The air
trapped in the padded material of the thermowrap
creates a dead air space, which helps to insulate the
sides of the battery case from the air temperature
found in the surrounding engine compartment.
REMOVAL
(1) Disconnect and isolate the negative battery
cable. (2) Disconnect the positive battery cable.
(3) Lift the battery thermowrap straight up to
remove from the battery.
INSTALLATION
(1) Position the thermowrap on the battery.
(2) Connect the negative and positive battery
cables.
Fig. 18 BATTERY TRAY POSITION & ORIENTATION
1 - BATTERY TRAY RETAINING FASTENERS
RS BATTERY SYSTEM8Fs-19
BATTERY TRAY (Continued)

ULES/POWERTRAIN CONTROL MODULE -
DESCRIPTION) section for more DTC information.The Charging system ªBatteryº light indicates
problems with the charging system (voltage too high/
low, generator failure, etc.). If an extreme condition is
indicated, the lamp will be illuminated. The signal to
activate the lamp is sent via the PCI bus circuits.
The lamp is located on the instrument panel. Refer
to the Instrument Cluster section for additional infor-
mation. The PCM uses the ambient air temperature sensor
to control the charge system voltage. This tempera-
ture, along with data from monitored line voltage, is
used by the PCM to vary the battery charging rate.
The system voltage is higher at cold temperatures
and is gradually reduced as the calculated battery
temperature increases. The ambient temperature sensor is used to control
the battery voltage based upon ambient temperature
(approximation of battery temperature). The PCM
maintains the optimal output of the generator by
monitoring battery voltage and controlling it to a
range of 13.5 - 14.7 volts based on battery tempera-
ture.
DIAGNOSIS AND TESTING - ON-BOARD
DIAGNOSTIC SYSTEM
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 OBD system. Some
circuits are checked continuously and some are
checked only under certain conditions. If the OBD system senses that a monitored circuit
is bad, it will put a DTC into electronic memory. The
DTC will stay in electronic memory as long as the
circuit continues to be bad. The PCM is programmed
to clear the memory after 40 good trip if the problem
does not occur again.
DIAGNOSTIC TROUBLE CODES
A DTC description can be read using the DRBIII t
scan tool. Refer to the appropriate Powertrain Diag-
nostic Procedures manual for information. A DTC does not identify which component in a cir-
cuit is bad. Thus, a DTC should be treated as a
symptom, not as the cause for the problem. In some
cases, because of the design of the diagnostic test
procedure, a DTC can be the reason for another DTC
to be set. Therefore, it is important that the test pro-
cedures be followed in sequence, to understand what
caused a DTC to be set. ERASING DIAGNOSTIC TROUBLE CODES
The DRBIII tScan Tool must be used to erase a
DTC. The following procedures may be used to diagnose
the charging system if: ² the check gauges lamp or battery lamp is illumi-
nated with the engine running ² the voltmeter (if equipped) does not register
properly ² an undercharged or overcharged battery condi-
tion occurs. Remember that an undercharged battery is often
caused by: ² accessories being left on with the engine not
running ² a faulty or improperly adjusted switch that
allows a lamp to stay on. Refer to Ignition-Off Draw
Test (Refer t o 8 - ELECTRICAL/BATTERY SYSTEM/
BATTERY - STANDARD PROCEDURE) ² loose generator belt.
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 DRBIII tscan tool.
Perform the following inspections before attaching
the scan tool. (1) Inspect the battery condition. Refer to the Bat-
tery section (Refer t o 8 - ELECTRICAL/BATTERY
SYSTEM - DIAGNOSIS AND TESTING) for proce-
dures. (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) or IPM (if
equipped) 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
RS CHARGING8Fs-21
CHARGING (Continued)

SPECIAL TOOLS
BATTERY TEMPERATURE
SENSOR
DESCRIPTION
(NGC Vehicles) The PCM incorporates a Battery
Temperature Sensor (BTS) on its circuit board.
OPERATION
The PCM uses the temperature of the battery area
to control the charge system voltage. This tempera-
ture, along with data from monitored line voltage, is
used by the PCM to vary the battery charging rate.
The system voltage is higher at cold temperatures
and is gradually reduced as temperature around the
battery increases. For vehicles with 1.6L engine, there is no physical
battery temp sensor in place to detect battery temp.
Rather, an algorithm buit in PCM is employed to pre-
dict battery temp using inlet air temp, vehicle speed,
and coolant temp, among other signals. The PCM
maintains the optimal output of the generator by
monitoring battery voltage and controlling it to a
range of 13.5 - 14.7 volts based on battery tempera-
ture. The system target voltage is 13.5 ± 14.7 volts.
However the actual voltage go below this during
heavy electrical loads and generator speeds. Also the
actual voltage can be lower than the target voltage
between the battery and the battery voltage sense
circuit, approximately 0.2 Ð 0.3 volts. The battery temperature sensor is also used for
OBD II diagnostics. Certain faults and OBD II mon-
itors are either enabled or disabled depending upon
the battery temperature sensor input (example: dis-
able purge and EGR, enable LDP). Most OBD II
monitors are disabled below 20ÉF.
REMOVAL
The battery temperature sensor is not serviced sep-
arately. If replacement is necessary, the PCM must
be replaced.
GENERATOR
DESCRIPTION
The generator is belt-driven by the engine. The
generator produces DC voltage at the B+ terminal. If
the generator is failed, the generator assembly sub-
components (generator and decoupler pulley) must be
inspected for individual failure and replaced accord-
ingly.
OPERATION
As the energized rotor begins to rotate within the
generator, the spinning magnetic field induces a cur-
rent into the windings of the stator coil. Once the
generator begins producing sufficient current, it also
provides the current needed to energize the rotor. The Y type stator winding connections deliver the
induced AC current to 3 positive and 3 negative
diodes for rectification. From the diodes, rectified DC
current is delivered to the vehicles electrical system
through the generator, battery, and ground terminals. Excessive or abnormal noise emitting from the gen-
erator may be caused by: ² Worn, loose or defective bearings
² Loose or defective drive pulley (2.4L) or decou-
pler (3.3/3.8L) ² Incorrect, worn, damaged or misadjusted drive
belt ² Loose mounting bolts
² Misaligned drive pulley
² Defective stator or diode
² Damaged internal fins
REMOVAL
REMOVAL - 2.4L
(1) Release hood latch and open hood.
(2) Disconnect battery negative cable.
(3) Disconnect the Inlet Air Temperature sensor.
(4) Remove the Air Box, refer to the Engine/Air
Cleaner for more information. (5) Remove the EVAP Purge solenoid from its
bracket and reposition. (6) Disconnect the push-in field wire connector
from back of generator. (7) Remove nut holding B+ wire terminal to back
of generator. (8) Separate B+ terminal from generator.
GENERATOR DECOUPLER 8433
RS CHARGING8Fs-23
CHARGING (Continued)