2004 CHRYSLER VOYAGER engine

service, the composition of this battery reduces gas-
sing and water loss at normal charge rates. However
these batteries may require additional distilled water
after years of service.
Maintenance-free batteriesare standard facto-
ry-installed equipment on all domestic versions of
this model. Male post type terminals made of a soft
lead material protrude from the top of the molded
plastic battery case (Fig. 6)to provide the means for
connecting the battery to the vehicle electrical sys-
tem. The battery positive terminal post is visibly
larger in diameter than the negative terminal post,
for easy identification. The lettersPOSandNEGare
also molded into the top of the battery case adjacent
to their respective positive and negative terminal
posts for additional identification confirmation.
This battery is designed to provide a safe, efficient
and reliable means of storing electrical energy in a
chemical form. This means of energy storage allows
the battery to produce the electrical energy required
to operate the engine starting system, as well as to
operate many of the other vehicle accessory systems
for limited durations while the engine and/or the
charging system are not operating. The battery is
made up of six individual cells that are connected in
series. Each cell contains positively charged plate
groups that are connected with lead straps to the
positive terminal post, and negatively charged plate
groups that are connected with lead straps to thenegative terminal post. Each plate consists of a stiff
mesh framework or grid coated with lead dioxide
(positive plate) or sponge lead (negative plate). Insu-
lators or plate separators made of a non-conductive
material are inserted between the positive and nega-
tive plates to prevent them from contacting or short-
ing against one another. These dissimilar metal
plates are submerged in a sulfuric acid and water
solution called an electrolyte.
Some factory-installed batteries have a built-in test
indicator (hydrometer). The color visible in the sight
glass of the indicator will reveal the battery condi-
tion. For more information on the use of the built-in
test indicator, refer toStandard Procedures. The
chemical composition of the metal coated plates
within the low-maintenance battery used in export
models reduces battery gassing and water loss at
normal charge and discharge rates. Therefore, the
battery should not require additional water in nor-
mal service. If the electrolyte level in this battery
does become low, distilled water must be added. How-
ever, rapid loss of electrolyte can be caused by an
overcharging condition. Be certain to diagnose the
charging system after replenishing the water in the
battery for a low electrolyte condition and before
returning the vehicle to service. Refer toCharging
Systemfor additional information.
The battery Group Size number, the Cold Cranking
Amperage (CCA) rating, and the Reserve Capacity
(RC) rating or Ampere-Hours (AH) rating can be
Fig. 5 BATTERY CELL CAP REMOVAL/
INSTALLATION - LOW-MAINTANANCE GASOLINE
ENGINE BATTERY - EXPORT
1 - BATTERY CELL CAP
2 - BATTERY CASE
Fig. 6 Maintenance-Free Battery - Domestic
1 - POSITIVE POST
2 - VENT
3 - CELL CAP
4 - VENT
5 - CELL CAP
6 - VENT
7 - NEGATIVE POST
8 - INDICATOR EYE (if equipped)
9 - ELECTROLYTE LEVEL
10 - PLATE GROUPS
11 - MAINTENANCE-FREE BATTERY
8F - 8 BATTERY SYSTEMRS
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:
²Micro 420 battery tester indicates battery is OK.
²Open-circuit voltage of the battery is 12.65 volts
or above.
²Battery 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
8F - 10 BATTERY SYSTEMRS
BATTERY (Continued)

SPIRAL-PLATE BATTERY CHARGE RATE TABLE
Voltage Minutes
14.4 volts maximum up to 10 minutes
13.0 to 14 volts up to 20 minutes
12.9 volts or less up to 30 minutes
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 eight
amperes will require a shorter charging 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 Battery Charging Time Table gives an indica-
tion of the time required to charge a typical battery
at room temperature based upon the battery state-of-
charge and the charger capacity.
SPIRAL-PLATE BATTERY CHARGING TIME
TABLE
Charging
Amperage5 Amps 8 Amps
Open Circuit
VoltageHours Charging @ 21É C
(70É F)
12.25 to 12.49 6 hours 3 hours
12.00 to 12.24 10 hours 5 hours
10.00 to 11.99 14 hours 7 hours
Below 10.00 18 hours 9 hours
STANDARD PROCEDURE - CONVENTIONAL
BATTERY CHARGING
Vehicles equipped with a diesel engine utilize a
unique spiral plate battery. This battery has a maxi-
mum charging voltage that must be used in order to
restore the battery to its full potential, failure to usethe 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:
²Micro 420 battery tester indicates battery is OK.
²Open-circuit voltage of the battery is 12.65 volts
or above.
²Battery passes Load Test multiple times.
WARNING: IF THE BATTERY SHOWS SIGNS OF
FREEZING, LEAKING, 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.
WARNING: IF THE BATTERY IS EQUIPPED WITH
REMOVABLE CELL CAPS, BE CERTAIN THAT EACH
OF THE CELL CAPS IS IN PLACE AND TIGHT
BEFORE THE BATTERY IS RETURNED TO SER-
VICE. PERSONAL INJURY AND/OR VEHICLE DAM-
AGE MAY RESULT FROM LOOSE OR MISSING
CELL CAPS.
CAUTION: Always disconnect and isolate the bat-
tery negative cable before charging a battery. Do
not exceed sixteen volts while charging a battery.
Damage to the vehicle electrical system compo-
nents may result.
CAUTION: Battery electrolyte will bubble inside the
battery case during normal battery charging. Elec-
trolyte boiling or being discharged from the battery
vents indicates a battery overcharging condition.
Immediately reduce the charging rate or turn off the
charger to evaluate the battery condition. Damage
to the battery may result from overcharging.
RSBATTERY SYSTEM8F-11
BATTERY (Continued)

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)

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)

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)

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)

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