INSTALLATION
(1) Install fan module on radiator.
(2) Install radiator.
(3) Tighten receiver/dryer lower bolt.
(4) Install radiator attaching bolts.
(5) Install lower and upper radiator hoses.
(6) Connect fan module.
(7) Install air cleaner housing and intake hose.
(8) Install radiator closure panel crossmember.
(9) Install power steering reservoir attaching bolts.
(10) Refill cooling system. Refer to Refilling cooling
system in this section for procedure.
(11) Connect battery.
WATER PUMP BELT Ð 2.5L VM DIESEL
REMOVAL
(1) Remove generator/power steering belt. Refer to
procedure in this section.
(2) Raise vehicle on hoist.
(3) Remove right side splash shield (Fig. 22).
(4) Loosen belt tensioner bracket bolts (Fig. 23).(5) Loosen adjuster lock nut.
(6) Loosen adjusting bolt, and remove belt.
INSTALLATION
(1) Install water pump belt.
(2) Turn adjusting bolt clockwise to tighten belt.
(3) Tighten lock nut.
(4) Tighten belt tensioner bracket bolts
(5) Lower vehicle.
(6) Install generator/power steering belt. Refer to
procedure in this section.
GENERATOR/POWER STEERING BELT Ð 2.5L VM
DIESEL
REMOVAL
(1) Loosen generator pivot bolt (Fig. 24).
(2) Loosen adjusting bracket bolt.
(3) Loosen adjusting nut.
(4) Remove generator/power steering belt.
INSTALLATION
(1) Install generator/power steering belt.
(2) Tighten adjusting nut.
(3) Tighten adjusting bracket bolt.
(4) Tighten generator pivot bolt.
CLEANING AND INSPECTION
WATER PUMP
Replace the water pump if it has any of the follow-
ing defects.
(1) Damage or cracks on the pump body.
Fig. 21 Radiator Closure Panel Crossmember
Fig. 22 Right Side Splash Shield
Fig. 23 Water Pump Belt Removal Ð 2.5L VM Diesel
7 - 10 COOLING SYSTEMNS/GS
REMOVAL AND INSTALLATION (Continued)
(2) Coolant leaks; if the seal is leaking, this will be
evident by traces of thick deposits of greenish-brown
dried glycol running down the pump body and com-
ponents below. A thin black stain below pump weep
hole is considered normal operation.
(3) Impeller rubs inside of the cylinder block 2.0L
engine. Impeller rubs inside of the water pump hous-
ing 2.5L VM diesel engine.
(4) Excessively loose or rough turning bearing.
NOTE: It is normal for the water pump to weep a
small amount of coolant from the weep hole (black
stain on water pump body). Do not replace the
water pump if this condition exists. Replace the
water pump if a heavy deposit or a steady flow of
green/brown engine coolant is evident on water
pump body from the weep hole (shaft seal failure).
Be sure to perform a thorough analysis before
replacing water pump.
ADJUSTMENTS
BELT TENSION GAUGE METHOD
Use belt tensioning Special Tool Kit C-4162 for:
CAUTION: The Burroughs gauge for the Poly-V
belt is not to be used on the V-belt. These gauges
are not interchangeable.
²For conventional V-belts affix the Burroughs
gauge (Special Tool C-4162) to the belt. Adjust the
belt tension for New or Used belt as prescribed in the
Belt Tension Chart. For a Poly-V belt affix the Poly-V
Burroughs gauge to the belt and then apply specified
tension to the belt as prescribed in the Belt Tension
Chart
Adjust the belt tension for aNeworUsedbelt as
prescribed in the Belt Tension Chart.
BELT TENSION CHART
Fig. 24 Generator/Power Steering Removal ± 2.5L
VM Diesel
ACCESSORY DRIVE
BELTGAUGE
2.0L GASOLINE ENGINE
GENERATOR AND AIR
CONDITIONINGNEW 667644 N (150
610 LBS).
USED 556 N (125 LBS.)
POWER STEERING NEW 578644 N (130
610 LBS).
USED 489 N (110 LBS).
2.5L VM DIESEL
WATER PUMP NEW N/A LBS.
USED N/A LBS.
GENERATOR /AIR
CONDITIONING/
POWER STEERINGNEW 667644 N (150
610 LBS).
USED 556 N (125 LBS).
NS/GSCOOLING SYSTEM 7 - 11
CLEANING AND INSPECTION (Continued)
SPECIFICATIONS
COOLING SYSTEM CAPACITY
TORQUE CHART
SPECIAL TOOLS
COOLING
2.0L Gasoline *10.6 liters (11 qts.)
2.5L VM Diesel *10.0 liters (10.6 qts.)
*Includes Heater and Coolant recovery/pressure Tank.
COMPONENT 2.0L
GASOLINE2.5L VM
Thermostat
Cover Bolts105 in-lbs 10.8 N´m (96 in.
lbs.)
Water Pump
Mounting Bolts12 N´m (105 in.
lbs.)22.6 N´m (204
in. lbs.)
Water Pump
Pulley BoltsN/A 27.5 N´m (240
in. lbs.)
Upper Radiator
Mounting
Bracket Bolts12 N´m (105 in.
lbs.)12 N´m (105 in.
lbs.)
Turbocharger
Oil Supply LineN/A 24.5 N´m (215
in. lbs.)
Turbocharger
Oil Return LineN/A 10.8 N´m (96 in.
lbs.)
Water Pump
Housing NutsN/A 9.5 N´m (84 in.
lbs.)
Water Manifold
BoltsN/A 11.2 N´m (96 in.
lbs.)
Coolant Bottle
Bolts2.0 N´m (18 in.
lbs.)10.8 N´m (96 in.
lbs.)
Belt Tension Gauge C-4162
7 - 12 COOLING SYSTEMNS/GS
use. Refer to Causes of Battery Discharging in this
Group for more information.
NOTE: CLEAR COLOR = Replace Battery
WARNING: DO NOT CHARGE, ASSIST BOOST,
LOAD TEST, OR ADD WATER TO THE BATTERY
WHEN CLEAR COLOR DOT IS VISIBLE. PERSONAL
INJURY MAY OCCUR.
A clear color dot shows electrolyte level in battery
is below the test indicator (Fig. 1). Water cannot be
added to a maintenance free battery. The battery
must be replaced. A low electrolyte level may be
caused by an over charging condition. Refer to Gen-
erator Test Procedures on Vehicle.
CAUSES OF BATTERY DISCHARGING
It is normal to have a small 5 to 25 milliamperes
continuous electrical draw from the battery. This
draw will take place with the ignition in the OFF
position, and the courtesy, dome, storage compart-
ments, and engine compartment lights OFF. The con-
tinuous draw is due to various electronic features or
accessories that require electrical current with the
ignition OFF to function properly. When a vehicle is
not used over an extended period of approximately 20
days the IOD fuse should be pulled. The fuse is
located in the power distribution center. Disconnec-
tion of this fuse will reduce the level of battery dis-
charge. Refer to Battery Diagnosis and Testing table
and to the proper procedures.
ABNORMAL BATTERY DISCHARGING
²Corroded battery posts, cables or terminals.
²Loose or worn generator drive belt.
²Electrical loads that exceed the output of the
charging system due to equipment or accessories
installed after delivery.
²Slow driving speeds in heavy traffic conditions
or prolonged idling with high-amperage electrical
systems in use.²Defective electrical circuit or component causing
excess Ignition Off Draw (IOD). Refer to Battery
Ignition Off Draw (IOD).
²Defective charging system.
²Defective battery.
BATTERY IGNITION OFF DRAW (IOD)
High current draw on the battery with the ignition
OFF will discharge a battery. After a dead battery is
serviced the vehicle Ignition Off Draw (IOD) should
be checked. Determine if a high current draw condi-
tion exists first check the vehicle with a test lamp.
(1) Verify that all electrical accessories are OFF.
²Remove key from ignition switch
²Turn off all lights
²Liftgate and glove box door is closed
²Sun visor vanity lights are OFF
²All doors are closed
²Allow the Illuminated Entry System to time out
in approximately 30 seconds, if equipped.
²During Transmission Control Module (TCM)
power down there will be 500 milliamperes present
for 20 minutes. Afterwards less than 1.0 milliampere.
(2) Disconnect battery negative cable (Fig. 4).
CAUTION: Always disconnect the meter before
opening a door.
(3) Using an multimeter, that has least a milliam-
pere range of 200 mA. Set meter to the highest mA
range. Install meter between the battery negative
cable and battery negative post (Fig. 5). Carefully
remove the test lamp without disconnecting the
meter. After all modules time-out the total vehicle
IOD should be less than 25 milliamperes. If ignition
off draw is more than 25 milliamperes go to Step 4.
(4) Each time the test lamp or milliampere meter
is disconnected and connected, all electronic timer
functions will be activated for approximately one
minute. The Body Control Module (BCM) ignition off
draw can reach 90 milliamperes.
(5) Remove the PDC fuses:
²Interior lamps
²Brake lamp
²IOD
(6) If there is any reading, with fuses removed
there is a short circuit in the wiring. Refer to Group
8W, wiring diagrams. If reading is less than 25 mA
go to Step 8.
(7) Install all fuses. After installing fuse, the cur-
rent can reach 90 mA. After time-out the reading
should not exceed 25 mA. If OK go to. If not, discon-
nect:
²Radio
²Body Control Module
²Remote Keyless Entry Module
Fig. 3 Test Indicator
NSBATTERY 8A - 3
DIAGNOSIS AND TESTING (Continued)
hydrometer reading. Always correct the specific grav-
ity for temperature variation. Test the specific grav-
ity of the electrolyte in each battery cell. Refer to the
information with the Hydrometer.
Example 1:
²Hydrometer reading: 1.260
²Electrolyte temperature: -7ÉC (20ÉF)
²Subtract specific gravity: -0.019
²Correction specific gravity: 1.241
Example 2:
²Hydrometer reading: 1.225
²Electrolyte temperature: -38ÉC (100ÉF)
²Add specific gravity: +0.013
²Correction specific gravity: 1.238
A fully charged relatively new battery has a spe-
cific gravity reading of 1.285 plus 0.015 or minus
0.010.
If the specific gravity of all cells is above 1.235, but
variation between cells is more than 50 points
(0.050), it is an indication that the battery is unser-
viceable.
If the specific gravity of one or more cells is less
than 1.235, recharge the battery at a rate of approx-
imately 5 amperes. Continue charging until three
consecutive specific gravity tests, taken at one-hour
intervals, are constant.
If the cell specific gravity variation is more than 50
points (0.050) at the end of the charge period, replace
the battery.When the specific gravity of all cells is above 1.235
and variation between cells is less than 50 points
(0.050), the battery may be tested under heavy load.
DIAGNOSIS AND TESTING
BATTERY DISCHARGING
CAUSE OF BATTERY DISCHARGING
It is normal to have a small 5 to 25 milliamperes
continuous electrical draw from the battery. This
draw will take place with the ignition in the OFF
position, and the courtesy, dome, storage compart-
ments, and engine compartment lights OFF. The con-
tinuous draw is due to various electronic features or
accessories that require electrical current with the
ignition OFF to function properly. When a vehicle is
not used over an extended period of approximately 20
days the IOD fuse should be disconnected. The fuse
is located in the power distribution center. Disconnec-
tion of this fuse will reduce the level of battery dis-
charge. Refer to Battery Diagnosis and Testing Chart
and to the proper procedures.
ABNORMAL BATTERY DISCHARGING
²Corroded battery posts, cables or terminals.
²Loose or worn generator drive belt.
²Electrical loads that exceed the output of the
charging system due to equipment or accessories
installed after delivery.
²Slow driving speeds in heavy traffic conditions
or prolonged idling with high-amperage electrical
systems in use.
²Defective electrical circuit or component causing
excess Ignition Off Draw (IOD). Refer to Battery
Ignition Off Draw (IOD).
²Defective charging system.
²Defective battery.
BATTERY IGNITION OFF DRAW
High current draw on the battery with the ignition
OFF will discharge a battery. After a dead battery is
serviced the vehicle Ignition Off Draw (IOD) should
be checked. Determine if a high current draw condi-
tion exists first check the vehicle with a test lamp.
(1) Verify that all electrical accessories are OFF.
²Remove key from ignition switch
²Turn off all lights
²Liftgate and glove box door is closed
²Sun visor vanity lights are OFF
²All doors are closed
²Allow the Illuminated Entry System to time out
in approximately 30 seconds, if equipped.
(2) Disconnect battery negative cable (Fig. 4).
Fig. 3 Battery Hydrometer
NS/GSBATTERY 8A - 3
DESCRIPTION AND OPERATION (Continued)
CHARGING SYSTEM
CONTENTS
page page
GENERAL INFORMATION
OVERVIEW............................. 1
DESCRIPTION AND OPERATION
BATTERY TEMPERATURE SENSOR.......... 2
CHARGING SYSTEM OPERATION........... 1
ELECTRONIC VOLTAGE REGULATOR......... 2
GENERATOR............................ 2
DIAGNOSIS AND TESTING
CHARGING SYSTEM RESISTANCE TESTS..... 4
CHARGING SYSTEM...................... 2CURRENT OUTPUT TEST.................. 4
ON-BOARD DIAGNOSTIC SYSTEM TEST...... 7
REMOVAL AND INSTALLATION
GENERATORÐ2.4L ENGINE................ 9
GENERATORÐ3.0L ENGINE................ 9
GENERATORÐ3.3/3.8 L ENGINE........... 10
SPECIFICATIONS
GENERATOR........................... 11
TORQUE.............................. 11
GENERAL INFORMATION
OVERVIEW
The battery, starting, and charging systems oper-
ate with one another, and must be tested as a com-
plete system. In order for the vehicle to start and
charge properly, all of the components involved in
these systems must perform within specifications.
Group 8A covers the battery, Group 8B covers the
starting system, and Group 8C covers the charging
system. Refer to Group 8W - Wiring Diagrams for
complete circuit descriptions and diagrams. We have
separated these systems to make it easier to locate
the information you are seeking within this Service
Manual. However, when attempting to diagnose any
of these systems, it is important that you keep their
interdependency in mind.
The diagnostic procedures used in these groups
include the most basic conventional diagnostic meth-
ods to the more sophisticated On-Board Diagnostics
(OBD) built into the Powertrain Control Module
(PCM). Use of an induction ammeter, volt/ohmmeter,
battery charger, carbon pile rheostat (load tester),
and 12-volt test lamp may be required.
All OBD-sensed systems are monitored by the
PCM. Each monitored circuit is assigned a Diagnos-
tic Trouble Code (DTC). The PCM will store a DTC in
electronic memory for any failure it detects. See the
On-Board Diagnostics Test in Group 8C - Charging
System for more information.
DESCRIPTION AND OPERATION
CHARGING SYSTEM OPERATION
The charging system consists of:
²Generator
²Electronic Voltage Regulator (EVR) circuitry
within the Powertrain Control Module (PCM)
²Ignition switch (refer to Group 8D, Ignition Sys-
tem for information)
²Battery (refer to Group 8A, Battery for informa-
tion)
²Temperature is measured by a sensor in the
PCM circuitry
²Wiring harness and connections (refer to Group
8W, Wiring for information)
The charging system is turned on and off with the
ignition switch. When the ignition switch is turned to
the ON position, battery voltage is applied to the
generator rotor through one of the two field termi-
nals to produce a magnetic field. The generator is
driven by the engine through a serpentine belt and
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.
All vehicles are equipped with On-Board Diagnos-
tics (OBD). All OBD-sensed systems, including the
EVR (field control) circuitry, are monitored by the
PCM. Each monitored circuit is assigned a Diagnos-
tic Trouble Code (DTC). The PCM will store a DTC in
electronic memory for any failure it detects. See On-
Board Diagnostic System Test in this group for more
information.
NSCHARGING SYSTEM 8C - 1
GENERATOR
The generator is belt-driven by the engine. It is
serviced only as a complete assembly. If the genera-
tor fails for any reason, the entire assembly must be
replaced.
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 vehicle electrical system
through the generator, battery, and ground terminals.
Noise emitting from the generator may be caused
by:
²Worn, loose or defective bearings
²Loose or defective drive pulley
²Incorrect, worn, damaged or misadjusted drive
belt
²Loose mounting bolts
²Misaligned drive pulley
²Defective stator or diode
BATTERY TEMPERATURE SENSOR
The temperature sensor, in the PCM, is used to
determine the battery temperature. This temperature
data, along with data from monitored line voltage, is
used by the PCM to vary the battery charging rate.
System voltage will be higher at colder temperatures
and is gradually reduced at warmer temperatures.
ELECTRONIC VOLTAGE REGULATOR
The Electronic Voltage Regulator (EVR) is not a
separate component. It is actually a voltage regulat-
ing circuit located within the Powertrain Control
Module (PCM). The EVR is not serviced separately. If
replacement is necessary, the PCM must be replaced.
Operation:The amount of DC current produced
by the generator is controlled by EVR circuitry con-
tained within the PCM. This circuitry is connected in
series with the generators second rotor field terminal
and its ground.
Voltage is regulated by cycling the ground path to
control the strength of the rotor magnetic field. The
EVR circuitry monitors system line voltage and bat-
tery temperature (refer to Battery Temperature Sen-
sor for more information). It then compensates and
regulates generator current output accordingly. Also
refer to Charging System Operation for additional
information.
DIAGNOSIS AND TESTING
CHARGING SYSTEM
When the ignition switch is turned to the ON posi-
tion, battery potential will register on the voltmeter.
During engine cranking a lower voltage will appear
on the meter. With the engine running, a voltage
reading higher than the first reading (ignition in ON)
should register.
The following are possible symptoms of a charging
system fault:
²The voltmeter does not operate 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. See Ignition-Off Draw Test
in Group 8A, Battery for more information.
The following procedures may be used to correct a
problem diagnosed as a charging system fault.
INSPECTION
(1) 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.
(2) Inspect all fuses in the fuseblock module and
Power Distribution Center (PDC) for tightness in
receptacles. They should be properly installed and
tight. Repair or replace as required.
(3) Inspect the electrolyte level in the battery.
Replace battery if electrolyte level is low.
(4) Inspect generator mounting bolts for tightness.
Replace or tighten bolts if required. Refer to the Gen-
erator Removal/Installation section of this group for
torque specifications.
(5) Inspect generator drive belt condition and ten-
sion. Tighten or replace belt as required. Refer to
Belt Tension Specifications in Group 7, Cooling Sys-
tem.
(6) Inspect automatic belt tensioner (if equipped).
Refer to Group 7, Cooling System for information.
(7) Inspect connections at generator field, battery
output, and ground terminals. Also check ground con-
nection at engine. They should all be clean and tight.
Repair as required.
8C - 2 CHARGING SYSTEMNS
DESCRIPTION AND OPERATION (Continued)
CHARGING SYSTEM RESISTANCE TESTS
These tests will show the amount of voltage drop
across the generator output wire from the generator
output (B+) terminal to the battery positive post.
They will also show the amount of voltage drop from
the ground (-) terminal on the generator or case
ground (Fig. 1) to the battery negative post.
A voltmeter with a 0±18 volt DC scale should be
used for these tests. By repositioning the voltmeter
test leads, the point of high resistance (voltage drop)
can easily be found.
PREPARATION
(1) Before starting test, make sure battery is in
good condition and is fully-charged. See Group 8A,
Battery for more information.
(2) Check condition of battery cables at battery.
Clean if necessary.
(3) Start the engine and allow it to reach normal
operating temperature.
(4) Shut engine off.
(5) Connect an engine tachometer.
(6) Fully engage the parking brake.
TEST
(1) Start engine.
(2) Place heater blower in high position.
(3) Turn on headlamps and place in high-beam
position.
(4) Turn rear window defogger on.
(5) Bring engine speed up to 2400 rpm and hold.
(6) Testing (+ positive) circuitry:
(a) Touch the negative lead of voltmeter directly
to battery positivePOST(Fig. 2).
(b) Touch the positive lead of voltmeter to the
B+ output terminal stud on the generator (not the
terminal mounting nut). Voltage should be no
higher than 0.6 volts. If voltage is higher than 0.6
volts, touch test lead to terminal mounting stud
nut and then to the wiring connector. If voltage is
now below 0.6 volts, look for dirty, loose or poor
connection at this point. Also check condition of the
generator output wire-to-battery bullet connector.
Refer to Group 8, Wiring for connector location. A
voltage drop test may be performed at each (-
ground) connection in this circuit to locate the
excessive resistance.
(7) Testing (- ground) circuitry:
(a) Touch the positive lead of voltmeter directly
to battery negativePOST.
(b) Touch the negative lead of voltmeter to the
generator case. Voltage should be no higher than
0.3 volts. If voltage is higher than 0.3 volts, touch
test lead to generator case and then to the engine
block. If voltage is now below 0.3 volts, look for
dirty, loose or poor connection at this point. A volt-
age drop test may be performed at each connectionin this circuit to locate the excessive resistance.
This test can also be performed between the gener-
ator case and the engine. If test voltage is higher
than 0.3 volts, check for corrosion at generator
mounting points or loose generator mounting.
CURRENT OUTPUT TEST
The current output test will determine if the
charging system can deliver its minimum test cur-
rent (amperage) output. Refer to the Specifications
section at the end of this group for minimum test
current (amperage) requirements.
The first part of this test will determine the com-
bined amperage output of both the generator and the
Electronic Voltage Regulator (EVR) circuitry.
PREPARATION
(1) Determine if any Diagnostic Trouble Codes
(DTC) exist. To determine a DTC, refer to On-Board
Diagnostics in this group. For repair, refer to the
appropriate Powertrain Diagnostic Procedures man-
ual.
(2) Before starting test, make sure battery is in
good condition and is fully-charged. See Group 8A,
Battery for more information.
(3) Check condition of battery cables at battery.
Clean if necessary.
(4) Perform the Voltage Drop Test. This will
ensure clean and tight generator/battery electrical
connections.
(5) Be sure the generator drive belt is properly
tensioned. Refer to Group 7, Cooling System for
information.
(6) A volt/amp tester equipped with both a battery
load control (carbon pile rheostat) and an inductive-
type pickup clamp (ammeter probe) will be used for
this test. Refer to operating instructions supplied
with tester. When using a tester equipped with an
inductive-type clamp, removal of wiring at the gener-
ator will not be necessary.
(7) Start the engine and allow it to reach operating
temperature.
(8) Shut engine off.
(9) Turn off all electrical accessories and all vehicle
lighting.
(10) Connect the volt/amp tester leads to the bat-
tery. Be sure the carbon pile rheostat control is in the
OPEN or OFF position before connecting leads. See
Load Test in Group 8A, Battery for more information.
Also refer to the operating instructions supplied with
test equipment.
(11) Connect the inductive clamp (ammeter probe).
Refer to the operating instructions supplied with test
equipment.
(12) If volt/amp tester is not equipped with an
engine tachometer, connect a separate tachometer to
the engine.
8C - 4 CHARGING SYSTEMNS
DIAGNOSIS AND TESTING (Continued)