Diagnosis And Testing; Battery; Built-In Test Indicator - Jeep 1996 Grand Cherokee Service Manual

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DESCRIPTION AND OPERATION (Continued)
BATTERY MOUNTING
The battery is mounted to a molded plastic tray
located in the right front corner of the engine com-
partment. Two U-nuts are held in formations on each
side of the tray. A holddown strap fits across the top
of the battery case and thermoguard. A bolt passes
through the holddown strap on each side of the bat-
tery, and is threaded into the U-nut on each side of
the battery tray.
The battery tray is fastened with three screws to
the front wheelhouse extension panel, forward of the
right front wheel. The tray is also secured to the
right fender inner shield with two screws.
A vacuum reservoir for the vehicle speed control
and heater-A/C systems is mounted to the underside
of the battery tray. Refer to Group 8H - Vehicle
Speed Control System and Group 24 - Heating and
Air Conditioning for more information on the vacuum
reservoir.
A hole in the bottom of the battery tray is fitted
with a battery temperature sensor on some models.
Models without the battery temperature sensor have
a plug fitted to this hole. Refer to Group 8C - Charg-
ing System for more information on the battery tem-
perature sensor.

DIAGNOSIS AND TESTING

BATTERY

The battery must be completely charged and the
top, posts, and terminal clamps should be properly
cleaned before diagnostic procedures are performed.
See Battery Charging in this group for more informa-
tion.
WARNING:
IF THE BATTERY SHOWS SIGNS OF FREEZING,
LEAKING, LOOSE POSTS, OR LOW ELECTROLYTE
LEVEL, DO NOT
CHARGE. THE BATTERY MAY ARC INTERNALLY
AND EXPLODE. PERSONAL INJURY AND/OR VEHI-
CLE DAMAGE MAY RESULT.
EXPLOSIVE HYDROGEN GAS FORMS IN AND
AROUND THE BATTERY. DO NOT SMOKE, USE
FLAME, OR CREATE SPARKS NEAR THE BATTERY.
PERSONAL INJURY AND/OR VEHICLE DAMAGE
MAY RESULT.
THE BATTERY CONTAINS
WHICH IS POISONOUS AND CAUSTIC. AVOID CON-
TACT WITH THE SKIN, EYES, OR CLOTHING. IN
THE EVENT OF CONTACT, FLUSH WITH WATER
AND CALL A PHYSICIAN IMMEDIATELY. KEEP OUT
OF THE REACH OF CHILDREN.
IF THE BATTERY IS EQUIPPED WITH REMOV-
ABLE CELL CAPS, BE CERTAIN THAT EACH OF
THE CELL CAPS IS IN PLACE AND TIGHT BEFORE
TEST, ASSIST-BOOST,
SULFURIC
THE BATTERY IS RETURNED TO SERVICE. PER-
SONAL INJURY AND/OR VEHICLE DAMAGE MAY
RESULT FROM LOOSE OR MISSING CELL CAPS.
The condition of a battery is determined by two cri-
teria:
1. State-Of-Charge - This can be determined by
viewing the built-in test indicator, by checking the
specific gravity of the electrolyte (hydrometer test),
or by checking the battery voltage (open-circuit volt-
age test).
2. Cranking Capacity - This can be determined
by performing a battery load test, which measures
the ability of the battery to supply high-amperage
current.
First, determine the battery state-of-charge. This
can be done in one of three ways. If the battery has a
built-in test indicator, use this test to determine the
state-of-charge. If the battery has no test indicator,
but has removable cell caps, perform the hydrometer
test to determine the state-of-charge. If the cell caps
are not removable, or a hydrometer is not available,
perform the open-circuit voltage test to determine the
state-of-charge.
The battery must be charged before proceeding
with a load test if:
• The built-in test indicator has a black or dark
color visible.
• The temperature corrected specific gravity is
less than 1.235.
• The open-circuit voltage is less than 12.4 volts.
A battery that will not accept a charge is faulty,
and must be replaced. Further testing is not
required. A fully-charged battery must be load tested
to determine its cranking capacity. A battery that is
fully-charged, but does not pass the load test, is
faulty and must be replaced.
NOTE: Completely discharged batteries may take
OR several hours to accept a charge. See Charging A
Completely Discharged Battery in this group for
more information.
A battery is fully-charged when:
• All cells are gassing freely during charging.
• A green color is visible in the sight glass of the

built-in test indicator.

• Three corrected specific gravity tests, taken at
1-hour intervals, indicate no increase in the specific
ACID,
gravity.
• Open-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 or loose battery posts and terminal
clamps.
BATTERY 8A - 3