charging JEEP XJ 1995 Service And Repair Manual

JUMP STARTING, TOWING AND HOISTING
INDEX
page page
Four-Wheel-Drive Vehicle Towing............. 12
Ground Clearance and Ramp Angle............ 11
Hoisting Recommendations.................. 10
Jump Starting Procedure..................... 9Towing Recommendations................... 10
Towing When Keys Are Not Available.......... 13
Two-Wheel-Drive Vehicle TowingÐXJ.......... 11
JUMP STARTING PROCEDURE
WARNING: DO NOT ATTEMPT TO PUSH OR TOW A
VEHICLE TO START THE ENGINE. UNBURNED
FUEL COULD ENTER THE EXHAUST CATALYTIC
CONVERTER AND IGNITE AFTER THE ENGINE IS
STARTED. THIS COULD CAUSE THE CONVERTER
TO OVERHEAT AND RUPTURE.
WARNING: REVIEW ALL SAFETY PRECAUTIONS
AND WARNINGS IN GROUP 8A, BATTERY/START-
ING/CHARGING SYSTEMS DIAGNOSTICS.
DO NOT JUMP START A FROZEN BATTERY, PER-
SONAL INJURY CAN RESULT.
DO NOT JUMP START WHEN MAINTENANCE
FREE BATTERY INDICATOR DOT IS YELLOW OR
BRIGHT COLOR.
DO NOT JUMP START A VEHICLE WHEN THE
BATTERY FLUID IS BELOW THE TOP OF LEAD
PLATES.
DO NOT ALLOW JUMPER CABLE CLAMPS TO
TOUCH EACH OTHER WHEN CONNECTED TO A
BOOSTER SOURCE.
DO NOT USE OPEN FLAME NEAR BATTERY.
REMOVE METALLIC JEWELRY WORN ON HANDS
OR WRISTS TO AVOID INJURY BY ACCIDENTAL
ARCING OF BATTERY CURRENT.
WHEN USING A HIGH OUTPUT BOOSTING DE-
VICE, DO NOT ALLOW BATTERY VOLTAGE TO EX-
CEED 16 VOLTS. REFER TO INSTRUCTIONS
PROVIDED WITH DEVICE BEING USED.
CAUTION: When using another vehicle as a
booster, do not allow vehicles to touch. Electrical
systems can be damaged on either vehicle.
TO JUMP START A DISABLED VEHICLE:
(1) Raise hood on disabled vehicle and visually in-
spect engine compartment for:
²Battery cable clamp condition, clean if necessary.
²Frozen battery.
²Yellow or bright color test indicator, if equipped.
²Low battery fluid level.
²Generator drive belt condition and tension.²Fuel fumes or leakage, correct if necessary.
CAUTION: If the cause of starting problem on dis-
abled vehicle is severe, damage to booster vehicle
charging system can result.
(2) When using another vehicle as a booster
source, turn off all accessories, place gear selector in
park or neutral, set park brake and operate engine at
1200 rpm.
(3) On disabled vehicle, place gear selector in park
or neutral and set park brake. Turn off all accesso-
ries.
(4) Connect jumper cables to booster battery. RED
clamp to positive terminal (+). BLACK clamp to neg-
ative terminal (-). DO NOT allow clamps at opposite
end of cables to touch, electrical arc will result. Re-
view all warnings in this procedure.
(5) On disabled vehicle, connect RED jumper cable
clamp to positive (+) terminal. Connect BLACK
jumper cable clamp to engine ground as close to the
ground cable attaching point as possible (Fig. 1).
Fig. 1 Jumper Cable ConnectionsÐTypical
JLUBRICATION AND MAINTENANCE 0 - 9

line. You may encounter fuels containing 3 percent or
more methanol along with other alcohols called cosol-
vents.
Problems that are the result of using methanol/gas-
oline blends are not the responsibility of Chrysler
Corporation. They may not be covered by the vehicle
warranty.
MTBE/ETBE
Gasoline and MTBE (Methyl Tertiary Butyl Ether)
blends are a mixture of unleaded gasoline and up to
15 percent MTBE. Gasoline and ETBE (Ethyl Ter-
tiary Butyl Ether) are blends of gasoline and up to
17 percent ETBE. Gasoline blended with MTBE or
ETBE may be used.
CLEAN AIR GASOLINE
Many gasolines are now being blended that con-
tribute to cleaner air, especially in those areas of the
country where air pollution levels are high. These
new blends provide a cleaner burning fuel and some
are referred to asReformulated Gasoline.
In areas of the country where carbon monoxide lev-
els are high, gasolines are being treated with oxygen-
ated materials such as MTBE, ETBE and ethanol.
Chrysler Corporation supports these efforts toward
cleaner air and recommends the use of these gaso-
lines as they become available.
IGNITION CABLES, DISTRIBUTOR CAP AND
ROTOR
Inspect and test ignition cables, distributor cap and
rotor when the spark plugs are replaced. Oil and
grime should be cleaned from the ignition cables and
distributor cap to avoid possible spark plug fouling.
Mopar Foamy Engine Degreaser or equivalent is rec-
ommended for cleaning the engine compartment. For
proper service and diagnostic procedures refer to
Group 8D, Ignition System.
IGNITION TIMING
The ignition timing for 2.5L and 4.0L engines is
not adjustable. Refer to the specifications listed on
the engine Emission Control Information Label. Re-
fer to Group 25, Emission Control Systems for addi-
tional information.
SPARK PLUGS
Ignition spark plugs should be replaced at the
mileage interval described in the Lubrication and
Maintenance Schedules. Refer to the General Infor-
mation section of this group. For proper service pro-
cedures refer to Group 8D, Ignition Systems.
BATTERY
WARNING: WEAR SAFETY GLASSES, RUBBER
GLOVES AND PROTECTIVE CLOTHING WHEN HAN-DLING/SERVICING A BATTERY. THE BATTERY
ELECTROLYTE CONTAINS SULFURIC ACID AND
WILL CAUSE HARM IF IT CONTACTS SKIN, EYES
OR CLOTHING. IT WILL ALSO DAMAGE PAINTED
(AS WELL AS UN-PAINTED) SURFACES OF A VEHI-
CLE. IF SULFURIC ACID CONTACTS ANY OF
THESE, FLUSH IMMEDIATELY WITH LARGE
AMOUNTS OF WATER. IF SULFURIC ACID CON-
TACTS SKIN OR EYES, GET IMMEDIATE MEDICAL
ATTENTION. DO NOT SMOKE IN THE VICINITY OF A
BATTERY. KEEP OPEN FLAMES AND SPARKS
AWAY FROM BATTERY FILLER CAPS BECAUSE
EXPLOSIVE GAS IS ALWAYS PRESENT.
Inspect battery tray, hold down and terminal con-
nections when other under hood service is performed.
For proper diagnostic procedures refer to Group 8A,
Battery/Starting/Charging System Diagnostics. For
service and cleaning procedures refer to Group 8B,
Battery/Starter Service.
Care should be taken when disposing a bat-
tery after removal from a vehicle. Lead-acid
batteries are highly poisonous and, when indis-
criminately disposed, could create a problem
for the environment. Contact the applicable lo-
cal city or county government agency to deter-
mine where automobile (lead-acid) batteries
can be properly disposed in the local area.
RUBBER AND PLASTIC COMPONENT INSPECTION
CAUTION: Plastic hoses or wire harness covers will
melt or deform when exposed to heat from exhaust
system or engine manifolds.
Position plastic or rubber components away from
moving parts in engine compartment or under vehi-
cle, or damage will result.
Do not allow rubber engine mounts or other com-
ponents to become oil contaminated, repair cause
of oil contamination and clean area.
All rubber and plastic components should be in-
spected when engine compartment or under vehicle
service is performed. When evidence of deterioration
exists, replacement is required. To reduce deteriora-
tion of rubber components, Chrysler Corporation rec-
ommends Mopar Foamy Engine Degreaser or
equivalent be used to clean engine compartment of
oil and road grime.
EMISSION CONTROL SYSTEM
Inspect all emission control components and hoses
when other under hood service is performed. Refer to
emission system Vacuum Hose Label located on the
inside of the hood in the engine compartment and
Group 25, Emission Control Systems for proper ser-
vice procedures.
0 - 20 LUBRICATION AND MAINTENANCEJ

INSPECTING FOR INLET RESTRICTIONS
Inadequate heater performance may be caused by a
metal casting restriction in the water pump heater
hose inlet.
DO NOT WASTE reusable coolant. If solution is
clean, drain coolant into a clean container for reuse.
WARNING: DO NOT REMOVE THE CYLINDER
BLOCK DRAIN PLUGS OR LOOSEN THE RADIATOR
DRAINCOCK WITH THE SYSTEM HOT AND UNDER
PRESSURE. SERIOUS BURNS FROM THE COOL-
ANT CAN OCCUR.
(1) Drain sufficient coolant from the radiator to de-
crease the level below the water pump heater hose
inlet.
(2) Remove the heater hose.
(3) Inspect the inlet for metal casting flash or
other restrictions.
Remove the pump from engine before remov-
ing restriction to prevent contamination of the
coolant with debris. Refer to Water Pump Re-
moval.
WATER PUMPSÐREMOVAL/INSTALLATION
REMOVALÐALL MODELS
CAUTION: If the water pump is replaced because of
mechanical damage, the fan blades and viscous fan
drive should also be inspected. These components
could have been damaged due to excessive vibra-
tion.The water pump on all models can be removed
without discharging the air conditioning system (if
equipped).
CAUTION: All engines have a reverse (counter-
clockwise) rotating water pump. The letter R is
stamped into the back of the water pump impeller
(Fig. 1) to identify. Engines from previous model
years, depending upon application, may be
equipped with a forward (clockwise) rotating water
pump. Installation of the wrong water pump will
cause engine over heating.
The water pump impeller is pressed on the rear of
the pump shaft and bearing assembly. The water
pump is serviced only as a complete assembly.
WARNING: DO NOT REMOVE THE BLOCK DRAIN
PLUG(S) OR LOOSEN RADIATOR DRAINCOCK
WITH THE SYSTEM HOT AND UNDER PRESSURE.
SERIOUS BURNS FROM COOLANT CAN OCCUR.
DO NOT WASTE reusable coolant. If the solution
is clean, drain coolant into a clean container for re-
use.
(1) Disconnect negative battery cable at battery.
(2) Drain the cooling system. Refer to Draining
Cooling System in this group.
(3)XJ models with 4.0L 6-cylinder engine
equipped with A/C or heavy duty cooling sys-
tem:
Loosen (but do not remove at this time) the four
water pump pulley-to-water pump hub mounting
bolts (Fig. 3).
XJ models with 4.0L 6-cylinder engine with-
out A/C or heavy duty cooling system; or any
2.5L 4-cylinder engines; or any YJ models:
Loosen (but do not remove at this time) the four
fan hub-to-water pump pulley mounting nuts (Fig. 4).
Fig. 2 Impeller TestÐTypical
Fig. 3 Water Pump Pulley Bolts
7 - 14 COOLING SYSTEM SERVICE PROCEDURESJ

ELECTRICAL
GROUP INDEX
Group Group
AUDIO SYSTEMS........................ 8F
BATTERY/STARTER/GENERATOR SERVICE.... 8B
BATTERY/STARTING/CHARGING SYSTEMS
DIAGNOSTICS......................... 8A
CHIME/BUZZER WARNING SYSTEMS........ 8U
HORNS................................ 8G
IGNITION SYSTEMS...................... 8D
INSTRUMENT PANEL AND GAUGES......... 8E
LAMPS................................ 8L
OVERHEAD CONSOLE.................... 8C
POWER LOCKS.......................... 8P
POWER MIRRORS....................... 8TPOWER SEATS.......................... 8R
POWER WINDOWS....................... 8S
REAR WINDOW DEFOGGER............... 8N
RESTRAINT SYSTEMS................... 8M
TURN SIGNAL AND HAZARD WARNING
SYSTEMS............................. 8J
VEHICLE SPEED CONTROL SYSTEM......... 8H
WIPER AND WASHER SYSTEMS............ 8K
XJ WIRING DIAGRAMS-LEFT HAND DRIVE . . . 8W
XJ WIRING DIAGRAMS-RIGHT HAND DRIVE . 8W
YJ WIRING DIAGRAMS.................. 8W
BATTERY/STARTING/CHARGING SYSTEMS DIAGNOSTICS
CONTENTS
page page
BATTERY............................... 2
CHARGING SYSTEM..................... 17
IGNITION-OFF DRAW.................... 10SPECIFICATIONS........................ 23
STARTING SYSTEM...................... 11
USING ON-BOARD DIAGNOSTIC SYSTEM.... 22
GENERAL INFORMATION
The battery, starting, and charging systems operate
with one another; therefore, they must be tested as a
complete 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 battery, starting (Fig. 1) and
charging (Fig. 2) system diagnostic procedures. These
procedures include the most basic conventional diag-
nostic methods, to On-Board Diagnostics (OBD) builtinto the Powertrain Control Module (PCM). Use of an
induction milliamp ammeter, volt/ohmmeter, battery
charger, carbon pile rheostat (load tester), and 12-
volt test lamp will 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 Us-
ing On-Board Diagnostic System in this group for
more information.
JELECTRICAL 8A - 1

BATTERY
GENERAL INFORMATION
The storage battery is a device used to store elec-
trical energy potential in a chemical form. When an
electrical load is applied to the battery terminals, an
electrochemical reaction occurs within the battery.
This reaction causes the battery to discharge electri-
cal current.
The battery is made up of 6 individual cells that
are connected in series. Each cell contains positively
charged plate groups made of lead oxide, and nega-
tively charged plate groups made of sponge lead.
These dissimilar metal plates are submerged in a
sulfuric acid and water solution called electrolyte.
As the battery discharges, a gradual chemical
change takes place within each cell. The sulfuric acid
in the electrolyte combines with the plate materials,
causing both plates to change to lead sulfate. At the
same time, oxygen from the positive plate material
combines with hydrogen from the sulfuric acid, caus-
ing the electrolyte to become mainly water.
The chemical changes within the battery are
caused by movement of excess or free electrons be-
tween the positive and negative plate groups. Thismovement of electrons produces a flow of electrical
current through the load device attached to the bat-
tery terminals.
As the plate materials become more similar chem-
ically, and the electrolyte becomes less acid, the volt-
age potential of each cell is reduced. However, by
charging the battery with a voltage higher than that
of the battery, the process is reversed.
Charging the battery gradually changes the sul-
fated lead plates back into sponge lead and lead ox-
ide, and the water back into sulfuric acid. This action
restores the difference in electron charges deposited
on the plates, and the voltage potential of the battery
cells.
For a battery to remain useful, it must be able to
produce high-amperage current over an extended pe-
riod. A battery must also be able to accept a charge,
so that its voltage potential may be restored.
In addition to producing and storing electrical en-
ergy, the battery serves as a capacitor or voltage sta-
bilizer for the vehicle electrical system. It absorbs
abnormal or transient voltages caused by switching
of any of the vehicle's electrical components.
The battery is vented to release excess gas that is
created when the battery is being charged or dis-
Fig. 1 Starting System Components (Typical)
Fig. 2 Charging System Components (Typical)
8A - 2 BATTERY/STARTING/CHARGING SYSTEMS DIAGNOSTICSJ

charged. However, even with these vents, hydrogen
gas can collect in or around the battery. If hydrogen
gas is exposed to flame or sparks, it can ignite.
If the electrolyte level is low, the battery could arc
internally and explode. If the battery is equipped
with removable cell caps, add distilled water when-
ever the electrolyte level is below the top of the
plates. If the battery cell caps cannot be removed, the
battery must be replaced when the electrolyte level is
low.
WARNING: DO NOT ATTEMPT TO ASSIST BOOST,
CHARGE, OR TEST BATTERY WHEN ELECTRO-
LYTE LEVEL IS BELOW THE TOP OF THE PLATES.
PERSONAL INJURY MAY OCCUR.
BATTERY RATINGS
Currently, there are 2 commonly accepted methods
for rating and comparing battery performance. These
ratings are called Cold Cranking Amperage (CCA),
and Reserve Capacity (RC). Be certain that a replace-
ment battery has CCA and RC ratings that equal or
exceed the original equipment specification for the
vehicle being serviced. See Battery Classifications
and Ratings charts in Specifications at the back of
this group.
COLD CRANKING AMPERAGE
The Cold Cranking Amperage (CCA) rating speci-
fies how much current (in amperes) the battery can
deliver for 30 seconds at -17.7ÉC (0ÉF). Terminal volt-
age must not fall below 7.2 volts during or after the
30 second discharge. The CCA required is generally
higher as engine displacement increases, depending
also upon the starter current draw requirements.
RESERVE CAPACITY
The Reserve Capacity (RC) rating specifies the
time (in minutes) it takes for battery terminal volt-
age to fall below 10.2 volts at a discharge rate of 25
amps. RC is determined with the battery fully-
charged at 26.7ÉC (80ÉF). This rating estimates how
long the battery might last after a charging system
failure, under minimum electrical load.
DIAGNOSIS
The battery must be completely charged and the
top, posts, and terminal clamps should be properly
cleaned before diagnostic procedures are performed.
Refer to Group 8B - Battery/Starter/Generator Ser-
vice for more information.
The condition of a battery is determined by two cri-
teria:
(1)State-Of-ChargeThis can be determined by
viewing the built-in test indicator, by checking spe-
cific gravity of the electrolyte (hydrometer test), or by
checking battery voltage (open circuit voltage test).(2)Cranking CapacityThis can be determined
by performing a battery load test, which measures
the ability of the battery to supply high-amperage
current.
If the battery has a built-in test indicator, use this
test first. If it has no test indicator, but has remov-
able cell caps, perform the hydrometer test first. If
cell caps are not removable, or a hydrometer is not
available, perform the open circuit voltage test first.
The battery must be charged before proceeding
with a load test if:
²the built-in test indicator has a black or dark color
visible
²the temperature corrected specific gravity is less
than 1.235
²the open circuit voltage is less than 12.4 volts.
A battery that will not accept a charge is faulty
and further testing is not required. A battery that is
fully-charged, but does not pass the load test is
faulty and must be replaced.
Completely discharged batteries may take
several hours to accept a charge. See Charging
Completely Discharged Battery.
A battery is fully-charged when:
²all cells are gassing freely during charging
²a green color is visible in the sight glass of the
built-in test indicator
²three corrected specific gravity tests, taken at
1-hour intervals, indicate no increase in specific grav-
ity
²open circuit voltage is 12.4 volts or greater.
ABNORMAL BATTERY DISCHARGING
Any of the following conditions can result in abnor-
mal battery discharging:
(1) Corroded battery posts and terminals.
(2) Loose or worn generator drive belt.
(3) Electrical loads that exceed the output of the
charging system, possibly due to equipment installed
after manufacture or repeated short trip use.
(4) Slow driving speeds (heavy traffic conditions) or
prolonged idling with high-amperage draw systems
in use.
(5) Faulty circuit or component causing excessive
ignition-off draw. See Ignition-Off Draw in this group
for diagnosis.
(6) Faulty charging system.
(7) Faulty or incorrect battery.
BUILT-IN TEST INDICATOR
A test indicator (hydrometer) built into the top of
the battery case, provides visual information for bat-
tery testing (Fig. 1). It is important when using the
test indicator that the battery be level and have a
clean sight glass to see correct indications. Additional
light may be required to view indicator.
JBATTERY/STARTING/CHARGING SYSTEMS DIAGNOSTICS 8A - 3

BATTERY DIAGNOSIS
8A - 4 BATTERY/STARTING/CHARGING SYSTEMS DIAGNOSTICSJ

WARNING: DO NOT USE OPEN FLAME AS A
SOURCE OF ADDITIONAL LIGHT FOR VIEWING
TEST INDICATOR. EXPLOSIVE HYDROGEN GAS
MAY BE PRESENT IN THE AREA SURROUNDING
BATTERY.
Like a hydrometer, the built-in test indicator mea-
sures the specific gravity of the electrolyte. Specific
gravity will indicate battery state-of-charge. How-
ever, the test indicator will not indicate cranking ca-
pacity of the battery. See Load Test in this group for
more information.
Look into the sight glass and note the color of the
indicator (Fig. 2). Refer to the following description,
as the color indicates:
GREENÐindicates 75% to 100% state-of-charge.
The battery is adequately charged for further test-
ing or return to use. If the vehicle will not crank for
a minimum of 15 seconds with a fully-charged bat-
tery, perform Load Test.
BLACK OR DARKÐindicates 0% to 75% state-of-
charge.
The battery is inadequately charged and must be
charged until green indicator (Fig. 2) is visible in
sight glass (12.4 volts or more) before the battery is
tested further or returned to use. See Abnormal Bat-
tery Discharging in this group to diagnose cause of
discharged condition.
YELLOW OR BRIGHTÐindicates low electrolyte
level.
The electrolyte level in the battery is below test in-
dicator (Fig. 2). A maintenance-free battery with non-
removable cell caps must be replaced if electrolyte
level is low. Water can be added to a low-mainte-
nance battery with removable cell caps. A low electro-
lyte level may be caused by an over-charging
condition. See Charging System in this group to di-
agnose an over-charging condition.
WARNING: DO NOT ATTEMPT TO CHARGE, TEST,
OR ASSIST BOOST BATTERY WHEN YELLOW OR
BRIGHT COLOR IS VISIBLE IN SIGHT GLASS OF
TEST INDICATOR. LOW ELECTROLYTE LEVEL CAN
ALLOW BATTERY TO ARC INTERNALLY AND EX-
PLODE. PERSONAL INJURY MAY OCCUR.
HYDROMETER TEST
The hydrometer test reveals the battery state-of-
charge by measuring the specific gravity of the elec-
trolyte. This test cannot be performed on batteries
with non-removable cell caps. If battery has non-re-
movable cell caps, see Built-In Test Indicator or Open
Circuit Voltage Test.
Specific gravity is a comparison of the density of
the electrolyte to the density of pure water. Pure wa-
ter has a specific gravity of 1.000, and sulfuric acid
has a specific gravity of 1.835. Sulfuric acid makes
up approximately 35% of the electrolyte by weight, or
24% by volume.
In a fully-charged battery the electrolyte will have
a temperature corrected specific gravity of 1.260 to
1.290. However, a specific gravity of 1.235 or above is
satisfactory for battery load testing and/or return to
service.
Before testing, visually inspect battery for any
damage (cracked case or cover, loose posts, etc.) that
would cause the battery to be faulty. Then remove
cell caps and check electrolyte level. Add distilled wa-
ter if electrolyte level is below the top of the battery
plates.
To use the hydrometer correctly, hold it with the
top surface of the electrolyte at eye level. Refer to the
hydrometer manufacturer's instructions for correct
use of hydrometer. Remove only enough electrolyte
from the battery so the float is off the bottom of the
hydrometer barrel with pressure on the bulb re-
leased.
Exercise care when inserting the tip of the hydrom-
eter into a cell to avoid damaging the plate separa-
tors. Damaged plate separators can cause premature
battery failure.
Hydrometer floats are generally calibrated to indi-
cate the specific gravity correctly only at 26.7ÉC
(80ÉF). When testing the specific gravity at any other
temperature, a correction factor is required.
The correction factor is approximately a specific
gravity value of 0.004, referred to as 4 points of spe-
cific gravity. For each 5.5ÉC above 26.7ÉC (10ÉF above
80ÉF), add 4 points. For each 5.5ÉC below 26.7ÉC
(10ÉF below 80ÉF), subtract 4 points. Always correct
Fig. 1 Built-In Test Indicator
Fig. 2 Built-In Test Indicator Sight Glass
JBATTERY/STARTING/CHARGING SYSTEMS DIAGNOSTICS 8A - 5

the specific gravity for temperature variation. Test
the specific gravity of the electrolyte in each battery
cell.
Example: A battery is tested at -12.2ÉC (10ÉF) and
has a specific gravity of 1.240. Determine the actual
specific gravity as follows:
(1) Determine the number of degrees above or be-
low 26.7ÉC (80ÉF):
26.6ÉC - -12.2ÉC = 38.8ÉC (80ÉF - 10ÉF = 70ÉF)
(2) Divide the result from step 1 by 5.5 (10):
38.8ÉC/5.5 = 7 (70ÉF/10 = 7)
(3) Multiply the result from step 2 by the temper-
ature correction factor (0.004):
7 x 0.004 = 0.028
(4) The temperature at testing was below 26.7ÉC
(80ÉF); therefore, the temperature correction is sub-
tracted:
1.240 - 0.028 = 1.212
The corrected specific gravity of the battery in this
example is 1.212.
If the specific gravity of all cells is above 1.235, but
variation between cells is more than 50 points
(0.050), the battery should be replaced.
If the specific gravity of one or more cells is less
than 1.235, charge the battery at a rate of approxi-
mately 5 amperes. Continue charging until 3 consec-
utive specific gravity tests, taken at 1-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 cell variation is less than 50 points (0.050), the
battery may be load tested.
OPEN CIRCUIT VOLTAGE TEST
A battery open circuit voltage (no load) test will
show state-of-charge of a battery. This test can be
used in place of the hydrometer test if a hydrometer
is not available, or for maintenance-free batteries
with non-removable cell caps.
Before proceeding with this test or load test,
completely charge battery as described in Bat-
tery Charging in this group.
Test battery open circuit voltage as follows:
(1) Before measuring open circuit voltage the sur-
face charge must be removed from the battery. Turn
headlamps on for 15 seconds, then allow up to 5 min-
utes for voltage to stabilize.
(2) Remove both battery cables, negative first.
(3) Using a voltmeter connected to the battery
posts (refer to instructions provided with voltmeter)
measure open circuit voltage (Fig. 3).
See Open Circuit Voltage chart. This voltage read-
ing will indicate state-of-charge, but will not reveal
cranking capacity. If a battery has an open circuit
voltage reading of 12.4 volts or greater, it may be
load tested. A battery that will not endure a load test
is faulty and must be replaced.
LOAD TEST
A battery load test will verify battery cranking ca-
pacity. The test is based on the Cold Cranking Am-
perage (CCA) rating of the battery. See Battery
Classifications and Ratings chart in Specifications, at
the back of this group.
WARNING: IF BATTERY SHOWS SIGNS OF FREEZ-
ING, LEAKING, LOOSE POSTS, OR LOW ELECTRO-
LYTE LEVEL, DO NOT LOAD TEST. PERSONAL
INJURY AND/OR VEHICLE DAMAGE MAY RESULT.
Before performing load test, the battery must
be FULLY-CHARGED.
(1) Remove both battery cables, negative first. Bat-
tery top and posts should be clean.
(2) Connect a suitable volt-ammeter-load tester
(Fig. 4) to the battery posts (Fig. 5). Refer to operat-
ing instructions provided with the tester being used.
Check the open circuit voltage (no load) of the bat-
tery. Open circuit voltage must be 12.4 volts or
greater.
(3) Rotate the load control knob (carbon pile rheo-
stat) to apply a 300 amp load for 15 seconds, then re-
turn the control knob to OFF (Fig. 6). This will
remove the surface charge from the battery.
(4) Allow the battery to stabilize to open circuit
voltage. It may take up to 5 minutes for voltage to
stabilize.
OPEN CIRCUIT VOLTAGE
Fig. 3 Testing Open Circuit Voltage
8A - 6 BATTERY/STARTING/CHARGING SYSTEMS DIAGNOSTICSJ

(5) Rotate the load control knob to maintain a load
equal to 50% of CCA rating (Fig. 7). After 15 seconds,
record the loaded voltage reading, then return the
load control knob to OFF.
(6) Voltage drop will vary with battery tempera-
ture at the time of the load test. Battery temperature
can be estimated by the ambient temperature over
the past several hours. If the battery has been
charged, boosted, or loaded a few minutes prior totest, the battery will be somewhat warmer. See Load
Test Temperature chart for proper loaded voltage
reading.
(7) If the voltmeter reading falls below 9.6 volts, at
a minimum battery temperature of 21ÉC (70ÉF), re-
place the battery.
BATTERY CHARGING
A battery is fully-charged when:
²all cells are gassing freely during charging
²a green color is visible in sight glass of built-in
test indicator
²three corrected specific gravity tests, taken at
1-hour intervals, indicate no increase in specific grav-
ity
²open circuit voltage is 12.4 volts or above.
WARNING: DO NOT ASSIST BOOST OR CHARGE A
BATTERY THAT HAS LOW ELECTROLYTE LEVEL
OR IS FROZEN. BATTERY MAY ARC INTERNALLY
AND EXPLODE.
WARNING: EXPLOSIVE HYDROGEN GAS FORMS IN
AND AROUND BATTERY. DO NOT SMOKE, USE
FLAME, OR CREATE SPARKS NEAR BATTERY.
Fig. 4 Volt-Amps-Load Tester (Typical)
Fig. 5 Volt-Ammeter-Load Tester Connections
Fig. 6 Remove Surface Charge from Battery
Fig. 7 Load 50% CCA Rating - Note Voltage
JBATTERY/STARTING/CHARGING SYSTEMS DIAGNOSTICS 8A - 7