Jeep Cherokee XJ 1999 Manual - page 9
the battery may be load tested to determine its
cranking capacity. Refer to Load Test in the Diagno-
sis and Testing section of this group for more infor-
mation.
OPEN-CIRCUIT VOLTAGE TEST
A battery open-circuit voltage (no load) test will
show the state-of-charge of a battery. This test can be
used in place of the hydrometer test when a hydrom-
eter is not available, or for maintenance-free batter-
ies with non-removable cell caps.
WARNING:
•
IF THE BATTERY SHOWS SIGNS OF FREEZ-
ING, LEAKING, LOOSE POSTS, OR LOW ELECTRO-
LYTE LEVEL, DO NOT TEST, ASSIST-BOOST, OR
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 SULFURIC ACID,
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
THE BATTERY IS RETURNED TO SERVICE. PER-
SONAL INJURY AND/OR VEHICLE DAMAGE MAY
RESULT FROM LOOSE OR MISSING CELL CAPS.
Before proceeding with this test, completely charge
the battery. Refer to Battery Charging in the Ser-
vice Procedures section of this group for the proper
battery charging procedures.
(1) Before measuring the open-circuit voltage, the
surface charge must be removed from the battery.
Turn on the head lamps for fifteen seconds, then
allow up to five minutes for the battery voltage to
stabilize.
(2) Disconnect and isolate both battery cables, neg-
ative cable first.
(3) Using a voltmeter connected to the battery
posts (see the instructions provided by the manufac-
turer of the voltmeter), measure the open-circuit volt-
age (Fig. 5).
See the Open-Circuit Voltage chart. This voltage
reading will indicate the battery state-of-charge, but
will not reveal its cranking capacity. If a battery has
an open-circuit voltage reading of 12.4 volts or
greater, it may be load tested to reveal its cranking
capacity. Refer to Load Test in the Diagnosis and
Testing section of this group for more information.
LOAD TEST
A battery load test will verify the battery cranking
capacity. The test is based on the Cold Cranking
Amperage (CCA) rating of the battery. See the label
affixed to the battery case, or refer to Battery Clas-
sifications and Ratings in the Specifications sec-
tion of this group for the CCA rating of the factory-
installed battery.
Fig. 5 Testing Open-Circuit Voltage - Typical
Open Circuit Voltage
Open Circuit Volts
Charge Percentage
11.7 volts or less
0%
12.0 volts
25%
12.2 volts
50%
12.4 volts
75%
12.6 volts or more
100%
XJ
BATTERY
8A - 9
DIAGNOSIS AND TESTING (Continued)