BATTERY OPEN CIRCUIT VOLTAGE TEST
An open circuit voltage no load test shows the
state of charge of a battery and whether it is ready
for a load test at 50 percent of the battery's cold
crank rating. Refer to Battery Load Test. If a battery
has open circuit voltage reading of 12.4 volts or
greater, and will not pass the load test, replace the
battery because it is defective. To test open circuit
voltage, perform the following operation.
(1) Remove both battery cables, negative cable
first. Battery top, cables and posts should be clean. If
green dot is not visible in indicator, charge the bat-
tery. Refer to Battery Charging Procedures.
(2) Connect a Volt/Ammeter/Load tester to the bat-
tery posts (Fig. 6). Rotate the load control knob of the
Carbon pile rheostat to apply a 300 amp load. Apply
this load for 15 seconds to remove the surface charge
from the battery, and return the control knob to off
(Fig. 7).
(3) Allow the battery to stabilize for 2 minutes,
and then verify the open circuit voltage (Fig. 9).
(4) This voltage reading will approximate the state
of charge of the battery. It will not reveal battery
cranking capacity. Refer to Battery Open Circuit
Voltage table.
SERVICE PROCEDURES
BATTERY CHARGING
WARNING: DO NOT CHARGE A BATTERY THAT
HAS EXCESSIVELY LOW ELECTROLYTE LEVEL.
BATTERY MAY SPARK INTERNALLY AND
EXPLODE. EXPLOSIVE GASES FORM OVER THE
BATTERY. DO NOT SMOKE, USE FLAME, OR CRE-
ATE SPARKS NEAR BATTERY. DO NOT ASSIST
BOOST OR CHARGE A FROZEN BATTERY. BAT-
TERY CASING MAY FRACTURE. BATTERY ACID IS
POISON, AND MAY CAUSE SEVERE BURNS. BAT-
TERIES CONTAIN SULFURIC ACID. AVOID CON-
TACT WITH SKIN, EYES, OR CLOTHING. IN THE
EVENT OF CONTACT, FLUSH WITH WATER AND
CALL PHYSICIAN IMMEDIATELY. KEEP OUT OF
REACH OF CHILDREN.
CAUTION: Disconnect the battery NEGATIVE cable
first. (Fig. 4) before charging battery to avoid dam-
age to electrical systems. Do not exceed 16.0 volts
while charging battery. Refer to the instructions
supplied with charging equipment
NOTE: The battery cannot be refilled with water, it
must be replaced.
A battery is considered fully charged when it will
meet all the following requirements.
²It has an open circuit voltage charge of at least
12.4 volts.
²It passes the 15 second load test, refer to the
Load Test Temperature chart.
²The built in test indicator dot is GREEN (Fig.
1).
Battery electrolyte will bubble inside of battery
case while being charged properly. If the electrolyte
boils violently, or is discharged from the vent holes
while charging, immediately reduce charging rate or
turn off charger. Evaluate battery condition. Battery
damage may occur if charging is excessive.
Some battery chargers are equipped with polarity
sensing devices to protect the charger or battery from
being damaged if improperly connected. If the bat-
tery state of charge is too low for the polarity sensor
to detect, the sensor must be bypassed for charger to
operate. Refer to operating instructions provided
with battery charger being used.
CAUTION: Charge battery until test indicator
appears green. Do not overcharge.
It may be necessary to jiggle the battery or vehicle
to bring the green dot in the test indicator into view.
Fig. 9 Testing Open Circuit Voltage
BATTERY OPEN CIRCUIT VOLTAGE
Open Circuit VoltsCharge Per-
centage
11.7 volts or less 0%
12.0 volts 25%
12.2 volts 50%
12.4 volts 75%
12.6 volts or more 100%
8A - 6 BATTERYNS
DIAGNOSIS AND TESTING (Continued)
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)
3.0L ENGINE
INDEX
page page
DESCRIPTION AND OPERATION
CAMSHAFT POSITION SENSOR............ 23
FIRING ORDERÐ3.0L.................... 23
MANIFOLD ABSOLUTE PRESSURE (MAP)
SENSOR............................. 23
REMOVAL AND INSTALLATION
CRANKSHAFT POSITION SENSOR.......... 25
ENGINE COOLANT TEMPERATURE SENSORÐ
3.0L................................. 25
IGNITION COILÐ3.OL.................... 24
MANIFOLD ABSOLUTE PRESSURE (MAP)
SENSORÐ3.0L........................ 24SPARK PLUG SERVICE................... 24
THROTTLE POSITION SENSOR............ 25
DISASSEMBLY AND ASSEMBLY
DISTRIBUTORÐ3.0L..................... 26
CLEANING AND INSPECTION
DISTRIBUTOR CAP...................... 26
DISTRIBUTOR ROTORÐ3.0L............... 27
SPECIFICATIONS
SPARK PLUG CABLE RESISTANCEÐ3.0L..... 27
SPARK PLUG........................... 27
TORQUE.............................. 27
DESCRIPTION AND OPERATION
FIRING ORDERÐ3.0L
MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR
The MAP sensor reacts to absolute pressure in the
intake manifold and provides an input voltage to the
Powertrain Control Module (PCM). As engine load
changes, manifold pressure varies. The changes in
engine load cause the MAP sensors resistance to
change. The change in MAP sensor resistance results
in a different input voltage to the PCM.
The input voltage level supplies the PCM with
information relating to ambient barometric pressure
during engine start-up (cranking) and engine load
while its operating. Based on MAP sensor voltage
and inputs from other sensors, the PCM adjusts
spark advance and the air-fuel mixture.
CAMSHAFT POSITION SENSOR
The PCM determines fuel injection synchronization
and cylinder identification from inputs provided by
the camshaft position sensor and crankshaft position
sensor. From the two inputs, the PCM determines
crankshaft position.
The 3.0L engine is equipped with a camshaft
driven mechanical distributor, containing a shaft
driven distributor rotor. The distributor is also
equipped with an internal camshaft position (fuel
sync) sensor (Fig. 1). This sensor provides fuel injec-
tion synchronization and cylinder identification to
the PCM.
The camshaft position sensor contains a hall effect
device callled a sync signal generator. This sync sig-
nal generator detects a rotating pulse ring (shutter)
on the distributor shaft. The pulse ring rotates 180
through the sync signal generator. Its signal is used
in conjunction with the crankshaft position sensor to
differentiate between fuel injection and spark events.
It is also used to synchronize the fuel injectors with
their respective cylinders.
When the leading edge of the shutter enters the
sync signal generator, the interruption of magnetic
field causes the voltage to switch high. This causes a
sync signal of approximately 5 volts.
When the trailing edge of the shutter leaves the
sync signal generator, the change of magnetic field
causes the sync signal voltage to switch low to 0
volts.
Since the shutter rotates at half crankshaft speed,
it may take 1 engine revolution during cranking for
the PCM to determine the position of piston number
6.
SPARK PLUG WIRE ROUTINGÐ3.0L ENGINE
NSIGNITION SYSTEM 8D - 23
MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR
REMOVAL
(1) Disconnect electrical connector from MAP sen-
sor.
(2) Remove 2 screws holding sensor to intake man-
ifold (Fig. 9).
(3) Remove sensor from manifold.
INSTALLATION
Reverse the above procedure for installation.
ENGINE COOLANT TEMPERATURE SENSOR
The Engine Coolant Temperature (ECT) sensor is
located below the ignition coil (Fig. 10).
REMOVAL
(1) Drain cooling system until coolant level is
below sensor. Refer to Group 7, Cooling System.
(2) Remove electrical connector from coil (Fig. 11).
(3) Remove coil mounting screws.
(4) Rotate coil away from engine coolant tempera-
ture sensor.
(5) Disconnect electrical connector from engine
coolant temperature sensor.
(6) Remove sensor from engine.
INSTALLATION
(1) Tighten the sensor to 7 N´m (60 in. lbs.) torque.
(2) Connect electrical connector to sensor.
(3) Fill cooling system. Refer to Group 7, Cooling
System.
(4) Install coil. Tighten coil mounting screws to 12
N´m (105 in. lbs.) torque.
(5) Connect electrical connector to coil.
THROTTLE POSITION SENSOR
Refer to Group 14, Fuel Injection Section, for
Removal/Installation.
KNOCK SENSORÐ3.3/3.8L
The knock sensor threads into the side of the cyl-
inder block in front of the starter (Fig. 12).
Fig. 8 Camshaft Position Sensor and Spacer
Fig. 9 Manifold Absolute Pressure Sensor
Fig. 10 Engine Coolant Temperature Sensor
Fig. 11 Ignition Coil Removal
8D - 32 IGNITION SYSTEMNS
REMOVAL AND INSTALLATION (Continued)
LAMPS
CONTENTS
page page
BULB APPLICATION..................... 17
HEADLAMP ALIGNMENT.................. 5
LAMP BULB SERVICE.................... 8LAMP DIAGNOSIS....................... 1
LAMP SERVICE........................ 13
LAMP DIAGNOSIS
INDEX
page page
GENERAL INFORMATION
HEADLAMP LEVELING MOTOR............. 2
INTRODUCTION........................ 1SAFETY PRECAUTIONS.................. 1
DIAGNOSIS AND TESTING
DIAGNOSTIC PROCEDURES.............. 2
GENERAL INFORMATION
INTRODUCTION
GS vehicles use lighting on the interior and exte-
rior of the vehicle for illuminating and indicating
purposes. Lighting circuits are protected by fuses.
Lighting circuits require an overload protected power
source, on/off device, lamps and body ground to oper-
ate properly. Plastic lamps require a wire in the har-
ness to supply body ground to the lamp socket.
Replace sockets and bulbs that are corroded.
Some of the interior and exterior lighting functions
are governed by the body controller. The headlamp,
dome, and the door ajar switches provide signals to
the body controller. The body controller in turn acti-
vates relay(s) in order to provide either a ground or
feed line to the appropriate lamp(s).
Wire connectors can make intermittent contact or
become corroded. Before coupling wire connectors,
inspect the terminals inside the connector. Male ter-
minals should not be bent or disengaged from the
insulator. Female terminals should not be sprung
open or disengaged from the insulator. Bent and
sprung terminals can be repaired using needle nose
pliers and pick tool. Corroded terminals appear
chalky or green. Corroded terminals should be
replaced to avoid recurrence of the problem symp-
toms.Begin electrical system failure diagnosis by testing
related fuses in the fuse block and power distribution
center. Verify that bulbs are in good condition and
test continuity of the circuit ground. Refer to Group
8W, Wiring Diagrams, for component location and cir-
cuit information.
SAFETY PRECAUTIONS
WARNING: EYE PROTECTION SHOULD BE USED
WHEN SERVICING GLASS COMPONENTS. PER-
SONAL INJURY CAN RESULT.
CAUTION: Do not touch the glass of halogen bulbs
with fingers or other possibly oily surface, reduced
bulb life will result.
Do not use bulbs with higher candle power than
indicated in the Bulb Application table at the end of
this group. Damage to lamp and/or Daytime Run-
ning Lamp Module can result.
Do not use fuses, circuit breakers or relays hav-
ing greater amperage value than indicated on the
fuse panel or in the Owners Manual.
When it is necessary to remove components to ser-
vice another, it should not be necessary to apply
excessive force or bend a component to remove it.
Before damaging a trim component, verify hidden
fasteners or captured edges are not holding the com-
ponent in place.
NS/GSLAMPS 8L - 1
BULB APPLICATION
INDEX
page page
GENERAL INFORMATION
INTRODUCTION....................... 17
CLEANING AND INSPECTION
HEADLAMP CLEANING.................. 17SPECIFICATIONS
EXTERIOR LAMP BULBS................. 17
INTERIOR LAMP BULBS................. 17
GENERAL INFORMATION
INTRODUCTION
The following Bulb Application Tables list the lamp
title on the left side of the column and trade number
or part number on the right.
CAUTION: Do not use bulbs that have a higher
candle power than the bulb listed in the Bulb Appli-
cation Table. Damage to lamp can result.
Do not touch halogen bulbs with fingers or other
possibly oily surfaces. Bulb life will be reduced.
If a halogen bulb is contaminated with oil, clean
bulb with denatured alcohol or ammonia based sol-
vent.
CLEANING AND INSPECTION
HEADLAMP CLEANING
This vehicle is equipped with plastic headlights
that are lighter and less susceptible to stone break-
age than glass headlights.
This plastic is not as scratch resistant as glass and
therefore a different lens cleaning procedures must
be followed.
To minimize the possibility of scratching the lenses
and reducing light output, avoid wiping with a dry
cloth. To remove road dirt, wash with a mild soap
solution followed by rinsing with water.
Do not use abrasive cleaning components, solvents,
steel wool or other aggressive material to clean the
lenses.
SPECIFICATIONS
EXTERIOR LAMP BULBS
LAMP BULB
Back-up.............................P21W
CHMSL (Non-Solar Tint)................P21W
CHMSL (Solar Tint)....................R10WLAMP BULB
Fog Lamp..............................H3
Headlamp..............................H4
License Plate..........................C5W
Front Turn Signal....................PY21W
Citylight..............................T4W
Front Side Repeater.....................T4W
Tail, Stop...........................P21/5W
Rear Turn Signal......................P21W
Rear Fog Lamp........................P21W
INTERIOR LAMP BULBS
LAMP BULB
ABS ................................PC194
AirBag .............................PC194
Alarm Set (Security/Immobilzer)..........PC194
Brake Warning.......................PC194
Center/Rear Reading Lamps...............578
Center/Rear Dome Lamps.................579
Cruise Indicator.......................PC194
Door Ajar Indicator....................PC194
Engine Compartment Lamps...............579
Engine Temp Indicator.................PC194
Front Door Courtesy......................567
Glove Box Lamp.........................194
Glow Plug Indicator (Diesel Engine Only) . . . PC194
High Beam Indicator...................PC194
Instrument Cluster....................PC194
IP/Ash Tray (Left Hand Drive Only).........161
Liftgate Flood Lamps.....................567
Liftgate Ajar Indicator...................PC74
Low Coolant Level (Diesel Engine Only).....PC74
Low Fuel Indicator....................PC194
Low Volts Warning.....................PC74
Low Washer Fluid......................PC74
Oil Pressure Indicator..................PC194
O/H Console Reading Lamps...............579
Seat Belt Indicator (Except Diesel).........PC74
Service Engine Soon...................PC194
Turn Signal..........................PC194
Visor Vanity Lamp...................6501966
NS/GSLAMPS 8L - 17
instrument cluster for 6 seconds after the instrument
cluster receives the message from the Body Control
Module. The seat belt lamp is therefore illuminated
for 6 seconds whenever the ignition switch is moved
to run/start position.
(1) While ignition is off, the seat belt lamp will not
be illuminated.
(2) The ignition power feed status will be updated
every 250 milliseconds or on change.
(3) This lamp will be checked by the instrument
cluster for 6 seconds with every run/start cycle of the
ignition switch.
TURN SIGNAL ON CHIME
The turn signal on chime will warn the driver that
the turn signals have been left on. When the body
control module receives a turn signal input for 6.4
km (4.0 miles), vehicle speed is greater than 24 km/h
(15 mph), the chime will sound continuously until the
turn signal is turned OFF. If vehicle speed drops
below 24 km/h (15 mph) prior to the warning being
activated, the accumulated distance traveled will be
reset. The turn signal chime is not activated when
the emergency flashers are turned on. This feature
can also be disabled in EEPROM. Chime rate: 50
chimes per minute.
For the turn signal warning system to operate:
²Must have input from either the right or left
turn signal lamps. Creates a voltage change between
0 and battery voltage.
²The vehicle speed sensor sends a message to the
Powertrain Control Module that vehicle has exceeded
24 km/h (15 mph) for 6.4 km (4.0 miles).
²When the above two conditions are met, the
chime will sound. The chime will stop when no fur-
ther voltage change is detected.²If hazard warning signals are pulsing, no chime
will sound.
²If speed drops below 24 km/h (15 mph) before
the warning is issued, the warning will not be issued
and the distance counter will be reset.
²If turn signal lamps are not working properly,
the chime will not sound.
²When using the scan tool, refer to the proper
Body Diagnostic Manual for the procedure.
WARNING LAMP ANNOUNCEMENT CHIME
The warning lamp announcement chime will warn
the driver to scan the instrument cluster to observe
which warning lamp is illuminated. Whenever the
volts, low fuel, low washer/coolant level, door ajar or
gate ajar lamps are first illuminated, the chime will
sound one tone. The door/liftgate ajar warning lamp
announcement chime sounds only if the vehicle speed
is above 2 m.p.h.
Two seconds after ignition switch is turned ON or
until the seat belt warning chime ends, all warning
announcement chimes will be consolidated into one
warning announcement. This will occur 2 seconds
after the seat belt warning chime ends. If a warning
announcement should occur while another warning
chime in progress (turn signal, low oil pressure or
high speed warnings), no additional chimes will
sound after the chime in progress ends. All associ-
ated lamps will be illuminated, and the active chime
will be the warning announcement.
NSCHIME WARNING/REMINDER SYSTEM 8U - 3
DIAGNOSIS AND TESTING (Continued)
SEAT BELT CHIME
The seat belt chime will sound for 4 to 8 seconds,
when the ignition is turned on and the driver's seat
belt is not buckled (seat belt switch is closed to
ground). This is a reminder to the driver to buckle
the seat belt. The seat belt lamp is controlled by the
mechanical instrument cluster. The cluster will also
illuminate the seat belt warning lamp for 6 seconds.
Buckling the driver's seat belt before the time out
has expired will cause the chime to stop immediately.
Chime rate: 38 to 62 chimes per minute.
To test the seat belt warning system, the ignition
switch must be in the OFF position for 1 minute
before starting the test. Turn the ignition switch to
the on position with the driver's seat belt not buck-
led. The seat belt warning lamp should light and the
chime should sound 4 to 8 seconds.
SEAT BELT LAMP
The seat belt lamp in the instrument cluster sig-
nals the vehicle passengers to fasten their seat belts.
The seat belt lamp is illuminated directly by the
instrument cluster for 6 seconds after the instrument
cluster receives the message from the Body Control
Module. The seat belt lamp is therefore illuminated
for 6 seconds whenever the ignition switch is moved
to run/start position.
(1) While ignition is off, the seat belt lamp will not
be illuminated.
(2) The ignition power feed status will be updated
every 250 milliseconds or on change.
(3) This lamp will be checked by the instrument
cluster for 6 seconds with every run/start cycle of the
ignition switch.
TURN SIGNAL ON CHIME
The turn signal on chime will warn the driver that
the turn signals have been left on. When the Body
Control Module receives a turn signal input for 1.6
km (1.0 miles), vehicle speed is greater than 24 km/h
(15 mph), the chime will sound continuously until the
turn signal is turned OFF. If vehicle speed drops
below 24 km/h (15 mph) prior to the warning being
activated, the accumulated distance traveled will be
reset. The turn signal chime is not activated whenthe emergency flashers are turned on. This feature
can also be disabled in EEPROM. Chime rate: 38 to
62 chimes per minute.
For the turn signal warning system to operate:
²Must have input from either the right or left
turn signal lamps. Creates a voltage change between
0 and battery voltage.
²The vehicle speed sensor sends a message to the
Powertrain Control Module that vehicle has exceeded
24 km/h (15 mph) for 1.6 km (1.0 miles).
²When the above two conditions are met, the
chime will sound. The chime will stop when no fur-
ther voltage change is detected.
²If hazard warning signals are pulsing, no chime
will sound.
²If speed drops below 24 km/h (15 mph) before
the warning is issued, the warning will not be issued
and the distance counter will be reset.
²If turn signal lamps are not working properly,
the chime will not sound.
²When using the scan tool, refer to the proper
Body Diagnostic Manual for the procedure.
WARNING LAMP ANNOUNCEMENT CHIME
The warning lamp announcement chime will warn
the driver to scan the instrument cluster to observe
which warning lamp is illuminated. Whenever the
volts, low fuel, low washer fluid, coolant level (gas/
diesel), low coolant level, engine temperature high
(diesel only), door ajar or gate ajar lamps are first
illuminated, the chime will sound one tone. The door/
liftgate ajar warning lamp announcement chime
sounds only if the vehicle speed is above 2 m.p.h.
Two seconds after ignition switch is turned ON or
until the seat belt warning chime ends, all warning
announcement chimes will be consolidated into one
warning announcement. This will occur 2 seconds
after the seat belt warning chime ends. If a warning
announcement should occur while another warning
chime in progress (turn signal, low oil pressure or
high speed warnings), no additional chimes will
sound after the chime in progress ends. All associ-
ated lamps will be illuminated, and the active chime
will be the warning announcement.
NS/GSCHIME WARNING/REMINDER SYSTEM 8U - 3
DIAGNOSIS AND TESTING (Continued)