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)
HEADLAMP DIAGNOSIS
CONDITION POSSIBLE CAUSES CORRECTION
HEADLAMPS ARE DIM
WITH ENGINE IDLING OR
IGNITION TURNED OFF1. Loose or corroded battery cables. 1. Clean and secure battery cable clamps
and posts.
2. Loose or worn generator drive belt. 2. Adjust or replace generator drive belt.
3. Charging system output too low. 3. Test and repair charging system. Refer to
Group 8A.
4. Battery has insufficient charge. 4. Test battery state-of -charge. Refer to
Group 8A.
5. Battery is sulfated or shorted. 5. Load test battery. Refer to Group 8A.
6. Poor lighting circuit Z1-ground. 6. Test for voltage drop across Z1-ground
locations. Refer to Group 8W.
7. Low beam headlamp / foglamp fuse
blown.7. Locate cause of blown fuse and repair.
HEADLAMP BULBS BURN
OUT FREQUENTLY1. Charging system output too high. 1. Test and repair charging system. Refer to
Group 8A.
2. Loose or corroded terminals or
splices in circuit.2. Inspect and repair all connectors and
splices. Refer to Group 8W.
HEADLAMPS ARE DIM
WITH ENGINE RUNNING
ABOVE IDLE1. Charging system output too low. 1. Test and repair charging system. Refer to
Group 8A.
2. Poor lighting circuit Z1-ground. 2. Test for voltage drop across Z1-ground
locations. Refer to Group 8W.
3. High resistance in headlamp circuit. 3. Test amperage draw of headlamp circuit.
4. Low beam headlamp / fog lamp
fuse blown.4. Locate cause of blown fuse and repair.
HEADLAMPS FLASH
RANDOMLY1. Poor lighting circuit Z1-ground. 1. Test for voltage drop across Z1-ground
locations, refer to Group 8W.
2. High resistance in headlamp circuit. 2. Test amperage draw of headlamp circuit.
3. Loose or corroded terminals or
splices in circuit.3. Inspect and repair all connectors and
splices. Refer to Group 8W.
HEADLAMPS DO NOT
ILLUMINATE1. No voltage to headlamps. 1. Repair open headlamp circuit. Refer to
Group 8W.
2. No Z1-ground at headlamps. 2. Repair circuit ground. Refer to Group 8W.
3. Faulty headlamp switch. 3. Replace headlamp switch.
4. Faulty headlamp dimmer (multi-
function) switch.4. Replace multi-function switch.
5. Broken connector terminal or wire
splice in headlamp circuit.5. Repair connector terminal or wire splice.
6. Defective or burned out bulb. 6. Replace bulb.
7. Body controller malfunction. 7. Refer to appropriate body controller
diagnostics.
NSLAMPS 8L - 3
DIAGNOSIS AND TESTING (Continued)
FOG LAMP DIAGNOSIS
CONDITION POSSIBLE CAUSES CORRECTION
FOG LAMPS ARE DIM WITH
ENGINE IDLING OR IGNITION
TURNED OFF.1. Loose or corroded battery
cables.1. Clean and secure battery cable
clamps and posts.
2. Loose or worn generator drive
belt.2. Adjust or replace generator drive
belt.
3. Charging system output too low. 3. Test and repair charging system.
Refer to Group 8A,
4. Battery has insufficient charge. 4. Test battery state-of -charge.
Refer to Group 8A.
5. Battery is sulfated or shorted. 5. Load test battery. Refer to Group
8A.
6. Poor lighting circuit Z1-ground. 6. Test for voltage drop across
Z1-ground locations. Refer to Group
8W.
FOG LAMP BULBS BURN OUT
FREQUENTLY1. Charging system output too high. 1. Test and repair charging system.
Refer to Group 8A.
2. Loose or corroded terminals or
splices in circuit.2. Inspect and repair all connectors
and splices. Refer to Group 8W.
FOG LAMPS ARE DIM WITH
ENGINE RUNNING ABOVE IDLE1. Charging system output too low. 1. Test and repair charging system.
Refer to Group 8A.
2. Poor lighting circuit Z1-ground. 2. Test for voltage drop across
Z1-ground locations. Refer to Group
8W.
3. High resistance in fog lamp
circuit.3. Test amperage draw of fog lamp
circuit.
FOG LAMPS FLASH RANDOMLY 1. Poor lighting circuit Z1-ground. 1. Test for voltage drop across
Z1-ground locations. Refer to Group
8W.
2. High resistance in fog lamp
circuit.2. Test amperage draw of fog lamp
circuit.
3. Faulty fog lamp switch. 3. Replace fog lamp switch.
4. Loose or corroded terminals or
splices in circuit.4. Inspect and repair all connectors
and splices. Refer to Group 8W.
FOG LAMPS DO NOT ILLUMINATE 1. Blown fuse for fog lamp. 1. Replace fuse. Refer to Group
8W.
2. No Z1-ground at fog lamps. 2. Repair circuit ground. Refer to
Group 8W.
3. Faulty fog lamp switch. 3. Replace fog lamp switch.
4. Broken connector terminal or
wire splice in fog lamp circuit.4. Repair connector terminal or wire
splice.
5. Defective or burned out bulb. 5. Replace bulb.
8L - 4 LAMPSNS
DIAGNOSIS AND TESTING (Continued)
FOG LAMP DIAGNOSIS
CONDITION POSSIBLE CAUSES CORRECTION
FOG LAMPS ARE DIM WITH
ENGINE IDLING OR IGNITION
TURNED OFF.1. Loose or corroded battery cables. 1. Clean and secure battery cable
clamps and posts.
2. Loose or worn alternator drive
belt.2. Adjust or replace alternator drive
belt.
3. Charging system output too low. 3. Test and repair charging system.
Refer to Group 8A,
4. Battery has insufficient charge. 4. Test battery state-of -charge.
Refer to Group 8A.
5. Battery is sulfated or shorted. 5. Load test battery. Refer to Group
8A.
6. Poor lighting circuit Z1-ground. 6. Test for voltage drop across
Z1-ground locations. Refer to Group
8W.
FOG LAMP BULBS BURN OUT
FREQUENTLY1. Charging system output too high. 1. Test and repair charging system.
Refer to Group 8A.
2. Loose or corroded terminals or
splices in circuit.2. Inspect and repair all connectors
and splices. Refer to Group 8W.
FOG LAMPS ARE DIM WITH
ENGINE RUNNING ABOVE IDLE1. Charging system output too low. 1. Test and repair charging system.
Refer to Group 8A.
2. Poor lighting circuit Z1-ground. 2. Test for voltage drop across
Z1-ground locations. Refer to Group
8W.
3. High resistance in fog lamp
circuit.3. Test amperage draw of fog lamp
circuit.
FOG LAMPS FLASH RANDOMLY 1. Poor lighting circuit Z1-ground. 1. Test for voltage drop across
Z1-ground locations. Refer to Group
8W.
2. High resistance in fog lamp
circuit.2. Test amperage draw of fog lamp
circuit.
3. Faulty fog lamp switch. 3. Replace fog lamp switch.
4. Loose or corroded terminals or
splices in circuit.4. Inspect and repair all connectors
and splices. Refer to Group 8W.
FOG LAMPS DO NOT
ILLUMINATE1. Blown fuse for fog lamp. 1. Replace fuse. Refer to Group 8W.
2. No Z1-ground at fog lamps. 2. Repair circuit ground. Refer to
Group 8W.
3. Faulty fog lamp switch. 3. Replace fog lamp switch.
4. Broken connector terminal or wire
splice in fog lamp circuit.4. Repair connector terminal or wire
splice.
5. Defective or burned out bulb. 5. Replace bulb.
NS/GSLAMPS 8L - 3
DIAGNOSIS AND TESTING (Continued)
LAMP BULB SERVICE
INDEX
page page
REMOVAL AND INSTALLATION
CENTER HIGH MOUNTED STOP LAMP
(CHMSL) BULB....................... 12
CITYLIGHT LAMP BULB.................. 9
FOG LAMP BULB........................ 9FRONT TURN SIGNAL LAMP BULB.......... 8
HEADLAMP BULB....................... 8
LICENSE PLATE LAMP BULB............. 12
SIDE REPEATER LAMP BULB............. 10
TAIL LAMP BULB....................... 10
REMOVAL AND INSTALLATION
HEADLAMP BULB
REMOVAL
(1) Release hood latch and open hood.
(2) Remove headlamp module from vehicle.
(3) Remove rubber seal boot (Fig. 1).
(4) Disengage retaining spring clip from headlamp
(Fig. 2).
(5) Pivot spring clip from headlamp bulb removal
path.
(6) Pull headlamp bulb from back of headlamp
(Fig. 3).
INSTALLATION
CAUTION: Do not touch the glass of halogen bulbs
with fingers of other possibly oily surface. Reduced
bulb life will result.
(1) Insert headlamp bulb to headlamp.
(2) Pivot spring clip over headlamp bulb.
(3) Engage retaining spring clip to headlamp.
(4) Install rubber seal boot.(5) Engage wire connector to headlamp bulb base.
(6) Install headlamp module into vehicle
(7) Verify headlamp alignment.
FRONT TURN SIGNAL LAMP BULB
REMOVAL
(1) Remove headlamp module from vehicle
Fig. 1 Rubber Boot Seal
Fig. 2 Headlamp Bulb Spring Clip
Fig. 3 Headlamp Bulb
8L - 8 LAMPSNS/GS
(2) Rotate front turn signal lamp socket one quar-
ter turn counterclockwise.
(3) Pull socket from back of lamp.
(4) Pull bulb from socket (Fig. 4).
INSTALLATION
(1) Align key on bulb base to groove in socket and
insert bulb into socket.
(2) Insert socket into back of headlamp.
(3) Rotate front turn signal socket clockwise one
quarter turn.
(4) Install headlamp module into vehicle.
(5) Verify lamp operation.
CITYLIGHT LAMP BULB
REMOVAL
(1) Remove the headlamp module.
(2) Pull citylight lamp from rubber bushing in
headlamp housing (Fig. 5).
(3) Pull bulb from socket (Fig. 6).
INSTALLATION
(1) Position citylight lamp bulb to lamp socket.
(2) Push bulb into socket.
(3) Push citylight lamp into bushing in headlamp
housing.
(4) Install headlamp module to vehicle.
FOG LAMP BULB
REMOVAL
(1) Remove fog lamp from vehicle.
(2) Remove rear cover from fog lamp.
(3) Disengage wire clip holding bulb in fog lamp
(Fig. 7).
(4) Hinge wire retainer clip out of bulb removal
path.
(5) Pull bulb from lamp.
(6) Disengage wire connector from fog lamp wire
harness.
Fig. 4 Front Turn Signal Lamp Bulb
Fig. 5 Citylight Lamp Socket
Fig. 6 Citylight Lamp Bulb
Fig. 7 Fog Lamp Bulb
NS/GSLAMPS 8L - 9
REMOVAL AND INSTALLATION (Continued)
LAMP SERVICE
INDEX
page page
GENERAL INFORMATION
HEADLAMP DIMMER SWITCH............. 13
HEADLAMP SWITCH.................... 13
REMOVAL AND INSTALLATION
CENTER HIGH MOUNTED STOP LAMP
(CHMSL)............................ 16FOG LAMP............................ 14
HEADLAMP LEVELING MOTOR............ 14
HEADLAMP MODULE................... 13
LICENSE PLATE LAMP.................. 15
SIDE REPEATER LAMP.................. 14
TAIL LAMP............................ 15
GENERAL INFORMATION
HEADLAMP SWITCH
Service procedures for the headlamp switch can be
found in Group 8E, Instrument Panel and Gauges.
More information can be found in Group 8W, Wiring
Diagrams.
HEADLAMP DIMMER SWITCH
The headlamp dimmer switch is incorporated into
the multi-function (turn signal) switch. Proper proce-
dures can be found in Group 8J, Turn Signal and
Flashers. More information can be found in Group
8W, Wiring Diagrams.
REMOVAL AND INSTALLATION
HEADLAMP MODULE
REMOVAL
(1) Release hood latch and open hood.
(2) Remove bolt holding headlamp module to radi-
ator closure panel (Fig. 1).
(3) From behind the radiator closure panel, remove
the nuts holding the headlamp module to the radia-
tor closure panel.
(4) Separate headlamp module from radiator clo-
sure panel.
(5) Disengage wire connector from headlamp bulb.
(6) Disengage wire connector from headlamp level-
ing motor.
(7) Disengage wire connector for front turn signal
and citylight lamps.(8) Separate headlamp module from vehicle.
INSTALLATION
(1) Position headlamp module to vehicle.
(2) Engage wire connector for front turn signal and
citylight lamps.
(3) Engage wire connector to headlamp leveling
motor.
(4) Engage wire connector to headlamp bulb.
(5) Position headlamp module to radiator closure
panel.
(6) Press headlamp module rearward until module
is fully seated onto mounting studs.
(7) Install nuts to hold headlamp module to radia-
tor closure panel.
(8) Verify lamp operation.
Fig. 1 Headlamp Module
NS/GSLAMPS 8L - 13
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