DODGE TOWN AND COUNTRY 2003 Service Manual

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:
²Battery Capacity- A completely discharged
heavy-duty battery requires twice the charging time
of a small capacity battery.
²Temperature- 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).
²Charger 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.
²State-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
8F - 12 BATTERY SYSTEMRS
BATTERY (Continued)
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CONVENTIONAL BATTERY CHARGING TIME TABLE
Charging
Amperage5 Amps10
Amps20 Amps
Open Circuit
VoltageHours 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 orgreater, 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:
²Electrical items left on.
²Faulty or improperly adjusted switches.
²Faulty or shorted electronic modules and compo-
nents.
²An internally shorted generator.
²Intermittent 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
RSBATTERY SYSTEM8F-13
BATTERY (Continued)
ProCarManuals.com

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 wateruntil the electrolyte
is above the hooks inside the battery cells (Fig. 11).
Fig. 10 BATTERY CELL CAP REMOVAL/
INSTALLATION - LOW-MAINTENANCE BATTERY
ONLY
1 - BATTERY CELL CAP
2 - BATTERY CASE
8F - 14 BATTERY SYSTEMRS
BATTERY (Continued)
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REMOVAL - BATTERY
WARNING: A SUITABLE PAIR OF HEAVY DUTY
RUBBER GLOVES AND SAFETY GLASSES SHOULD
BE WORN WHEN REMOVING OR SERVICING A
BATTERY.
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 Downsin 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.
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
RSBATTERY SYSTEM8F-15
BATTERY (Continued)
ProCarManuals.com

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.
(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 toWiring Diagramsin 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 toWiring Diagramsin theindex 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
8F - 16 BATTERY SYSTEMRS
BATTERY HOLDDOWN (Continued)
ProCarManuals.com

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
test, be certain that the following procedures are
accomplished:
²The battery is fully-charged and load tested.
Refer to Standard Procedures for the proper battery
charging and load test procedures.
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 the engine from starting, remove the
Automatic Shut Down (ASD) relay. The ASD relay is
located in the Intelligent Power Module (IPM), in the
engine compartment. See the fuse and relay layout
label affixed to the underside of the IPM cover for
ASD relay identification and location.
(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. 13). 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.
(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. 14). Rotate and hold the ignition
switch in the Start position. Observe the voltmeter. If
voltage is detected, correct the poor connection
between the battery positive cable terminal clamp
and the battery positive terminal post.
(3) Connect the voltmeter to measure between the
battery positive cable terminal clamp and the starter
solenoid B(+) terminal stud (Fig. 15). 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.(4) Connect the voltmeter to measure between the
battery negative cable terminal clamp and a good
clean ground on the engine block (Fig. 16). 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.
Fig. 13 Testing Battery Negative Connection
Resistance
1 - VOLTMETER
2 - BATTERY
Fig. 14 Testing Battery Positive Connection
Resistance
1 - VOLTMETER
2 - BATTERY
RSBATTERY SYSTEM8F-17
BATTERY CABLES (Continued)
ProCarManuals.com

REMOVAL
The battery cables on this model may include por-
tions of wiring circuits for the generator and other
components on the vehicle. If battery cable replace-
ment is required, it will be necessary to extract the
cables out of the engine wire harness assembly. Use
care not to damage the other wires and circuits
which are also packaged into the engine wire harness
assembly.
(1) Turn the ignition switch to the Off position. Be
certain that all electrical accessories are turned off.
(2) Disconnect and isolate the negative battery
cable terminal.
(3) Remove the battery thermowrap (if equipped)
from the battery tray.
(4) Remove the tape from the engine wire harness
assembly, to access the desired battery cable.(5) One at a time, trace and disconnect the battery
cable retaining fasteners and routing clips until the
desired cable is free from the vehicle.
(6) Feed the battery cable out of the vehicle.
INSTALLATION
(1) Position the battery cable in the vehicle.
(2) One at a time, trace and install the battery
cable retaining fasteners and routing clips until the
desired cable is properly installed in the engine wire
harness assembly.
(3) Install the tape on the engine wire harness
assembly.
(4) Install the battery thermowrap (if equipped) on
the battery tray.
(5) Connect the negative battery cable terminal.
BATTERY TRAY
DESCRIPTION
The battery is mounted in a molded plastic battery
tray and support unit located in the left front corner
of the engine compartment. The battery tray and
support unit is secured with two nuts, one is located
directly under the battery and the other is located on
the right side of the tray which also serves as a cool-
ant bottle neck retaining bolt. An additional bolt is
located directly under the battery.
Fig. 15 Testing Battery Positive Cable Resistance
1 - BATTERY
2 - VOLTMETER
3 - STARTER MOTOR
Fig. 16 Testing Ground Circuit Resistance
1 - VOLTMETER
2 - BATTERY
3 - ENGINE GROUND
Fig. 17 RS BATTERY TRAY
1 - ENGINE VACUUM RESERVOIR
2 - BATTERY TRAY ASSEMBLY
3 - DRAINAGE HOSE
8F - 18 BATTERY SYSTEMRS
BATTERY CABLES (Continued)
ProCarManuals.com

The battery tray and support unit also includes a
engine vacuum reservoir, located in the rear of the
unit (Fig. 17). And a drainage hose, located in the
front of the unit (Fig. 17).
OPERATION
The battery tray provides a secure mounting loca-
tion and supports the battery. The battery tray also
provides the anchor point for the battery holddown
hardware. The battery tray and the battery hold-
down hardware combine to secure and stabilize the
battery in the engine compartment, which prevents
battery movement during vehicle operation. Unre-
strained battery movement during vehicle operation
could result in damage to the vehicle, the battery, or
both.
The battery tray used on this model also includes a
engine vacuum reservoir and drainage hose. The vac-
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
RSBATTERY SYSTEM8F-19
BATTERY TRAY (Continued)
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CHARGING
TABLE OF CONTENTS
page page
CHARGING
DESCRIPTION - CHARGING SYSTEM.......20
OPERATION - CHARGING SYSTEM.........20
DIAGNOSIS AND TESTING - ON-BOARD
DIAGNOSTIC SYSTEM.................21
SPECIFICATIONS
GENERATOR........................22
TORQUE............................22
SPECIFICATIONS - BATTERY
TEMPERATURE SENSOR...............22
SPECIAL TOOLS.......................23
BATTERY TEMPERATURE SENSOR
DESCRIPTION.........................23
OPERATION...........................23
REMOVAL.............................23
GENERATOR
DESCRIPTION.........................23OPERATION...........................23
REMOVAL
REMOVAL - 2.4L......................23
REMOVAL - 3.3/3.8L...................24
INSTALLATION
INSTALLATION - 2.4L..................24
INSTALLATION - 3.3/3.8L................24
GENERATOR DECOUPLER PULLEY
DESCRIPTION.........................25
OPERATION...........................25
DIAGNOSIS AND TESTING - GENERATOR
DECOUPLER PULLEY..................25
REMOVAL.............................26
INSTALLATION.........................26
VOLTAGE REGULATOR
DESCRIPTION.........................27
OPERATION...........................27
CHARGING
DESCRIPTION - CHARGING SYSTEM
The charging system consists of:
²Generator
²Decoupler Pulley (If equipped)
²Electronic Voltage Regulator (EVR) circuitry
within the Powertrain Control Module (PCM)
²Ignition switch (refer to the Ignition System sec-
tion for information)
²Battery (refer to the Battery section for informa-
tion)
²Ambient Air Temperature (If equipped)
²Inlet Air Temperature (calculated battery tem-
perature)(If equipped)
²Voltmeter (refer to the Instrument Cluster sec-
tion for information if equipped)
²Wiring harness and connections (refer to the
Wiring section for information)
²Accessory drive belt (refer to the Cooling section
for more information)
²Battery Temperature sensor (if equipped)
OPERATION - CHARGING SYSTEM
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. The ASD
relay is energized when the PCM grounds the ASD
control circuit. (SBEC vehicles) This voltage is con-
nected through the PCM or IPM (intelligent powermodule) (if equipped) and supplied to one of the gen-
erator field terminals (Gen. Source +) at the back of
the generator.
The generator is driven by the engine through a
serpentine belt and pulley or decoupler pulley
arrangement.
The amount of DC current produced by the gener-
ator is controlled by the EVR (field control) circuitry
contained within the PCM. This circuitry is con-
nected in series with the second rotor field terminal
and ground.
(SBEC vehicles) An Inlet air temperature sensor is
used to calculate the temperature near the battery.
This temperature data, along with data from moni-
tored line voltage (battery voltage sense circuit), is
used by the PCM to vary the battery charging rate.
This is done by cycling the ground path to control the
strength of the rotor magnetic field. The PCM then
compensates and regulates generator current output
accordingly to maintain system voltage at the tar-
geted system voltage based on battery temperature.
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 and
illuminate the (MIL) lamp. Refer to On-Board Diag-
nostics in the Electronic Control Modules(Refer to 8 -
ELECTRICAL/ELECTRONIC CONTROL MOD-
8F - 20 CHARGINGRS
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ULES/POWERTRAIN CONTROL MODULE -
DESCRIPTION) section for more DTC information.
The Check Gauges Lamp (if equipped) or Battery
Lamp monitors:charging system voltage,engine
coolant temperature and engine oil pressure. If an
extreme condition is indicated, the lamp will be illu-
minated. 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 information.
(If equipped with inlet air temperature sensor) The
PCM uses the inlet air temperature sensor to control
the charge system voltage. This temperature, 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 gradu-
ally 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. 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.
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 DRBIIIt
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 DTCto 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 DRBIIItScan Tool must be used to erase a
DTC.
The following procedures may be used to diagnose
the charging system if:
²the check gauges lamp or battery lamp 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
²a faulty or improperly adjusted switch that
allows a lamp to stay on. Refer to Ignition-Off Draw
Test (Refer to 8 - ELECTRICAL/BATTERY SYSTEM/
BATTERY - STANDARD PROCEDURE)
²loose 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 DRBIIItscan tool.
Perform the following inspections before attaching
the scan tool.
(1) Inspect the battery condition. Refer to the Bat-
tery section (Refer to 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.
RSCHARGING8F-21
CHARGING (Continued)
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